阅读说明：本技术 漏电流检测设备、漏电流检测方法和电动车辆 (Leakage current detection device, leakage current detection method, and electric vehicle ) 是由 咸相赫 金钟阮 于 2020-10-07 设计创作，主要内容包括：根据本公开的一种用于电动车辆中包括的电池的漏电流检测设备将与电池的负端子和电动车辆的底盘之间的电压对应的第一电压通过电容器传输到模数转换器。漏电流检测设备将与电池的正端子和底盘之间的电压对应的第二电压通过电容器传输到模数转换器。模数转换器使用负端子作为地,输出指示第一电压和第二电压的数字信号。漏电流检测设备基于数字信号来确定第一电压和第二电压,并且然后基于第一电压和第二电压来检测电池与底盘之间的漏电流。(A leakage current detection apparatus for a battery included in an electric vehicle according to the present disclosure transmits a first voltage corresponding to a voltage between a negative terminal of the battery and a chassis of the electric vehicle to an analog-to-digital converter through a capacitor. The leakage current detection device transmits a second voltage corresponding to a voltage between the positive terminal of the battery and the chassis to the analog-to-digital converter through the capacitor. The analog-to-digital converter outputs digital signals indicative of the first voltage and the second voltage using the negative terminal as a ground. The leakage current detection device determines a first voltage and a second voltage based on the digital signal, and then detects leakage current between the battery and the chassis based on the first voltage and the second voltage.)

1. An electric leakage detection apparatus for a battery included in an electric vehicle, the electric leakage detection apparatus comprising:

a first switch connected between the second node and a first node connected to a negative terminal of the battery;

a second switch connected between a fourth node and a third node connected to a positive terminal of the battery;

a first resistor connected between the second node and a fifth node connected to a chassis of the electric vehicle;

a second resistor connected between the fourth node and the fifth node;

a capacitor connected between the sixth node and the seventh node;

a first switching circuit configured to selectively connect the first resistor in parallel with the capacitor;

a second switching circuit configured to selectively connect the second resistor in parallel with the capacitor;

a third switching circuit arranged to selectively connect the capacitor between the first node and an eighth node;

an analog-to-digital converter (ADC) configured to generate a digital signal indicative of a voltage between the first node and the eighth node; and

a control unit operably coupled to the ADC,

wherein the control unit is configured to:

performing a first switching mode during a first period in which the control unit controls the first switch to an on state, controls the second switch to an off state, controls the first switching circuit to an on state, controls the second switching circuit to an off state, and controls the third switching circuit to an off state,

performing a second switching mode during a second period when the first switching mode ends, in which the control unit controls the first switching circuit to an off state, controls the second switching circuit to an off state, and controls the third switching circuit to an on state,

determining a first voltage indicative of a voltage of the first resistor based on a digital signal generated by the analog-to-digital converter during the second period,

performing a third switching mode during a third period, in which the control unit controls the first switch to be in an off state, controls the second switch to be in an on state, controls the first switch circuit to be in an off state, controls the second switch circuit to be in an on state, and controls the third switch circuit to be in an off state,

the second switching mode is executed during a fourth period when the third switching mode ends, in which the control unit controls the first switching circuit to an off state, controls the second switching circuit to an off state, and controls the third switching circuit to an on state,

determining a second voltage indicative of a voltage of the second resistor based on the digital signal generated by the analog-to-digital converter during the fourth time period, and

determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

2. The electrical leakage detection device according to claim 1, wherein the first switch circuit includes:

a third switch connected between the second node and the sixth node; and

a fourth switch connected between the fifth node and the seventh node,

the second switching circuit includes:

a fifth switch connected between the fifth node and the sixth node; and

a sixth switch connected between the fourth node and the seventh node, and

the third switching circuit includes:

a seventh switch connected between the sixth node and the first node; and

an eighth switch connected between the seventh node and the eighth node.

3. The electrical leakage detection device according to claim 1, further comprising:

a third resistor electrically connected in series with the first switch between the first node and the second node; and

a fourth resistor electrically connected in series with the second switch between the third node and the fourth node.

4. The electrical leakage detection device according to claim 3, wherein the resistance of the first resistor is equal to the resistance of the second resistor, and

the resistance of the third resistor is equal to the resistance of the fourth resistor, an

Wherein the control unit is configured to determine an insulation resistance indicating an insulation state between the battery and the chassis using the following equation 1:

[ formula 1]

Wherein, V₁Is said first voltage, V₂Is said second voltage, R₁Is the resistance of the first resistor, R₃Is the resistance of the third resistor, and V_BattIs the voltage of the battery.

5. The electrical leakage detection apparatus according to claim 4, wherein the control unit is configured to determine that electrical leakage between the battery and the chassis occurs when the insulation resistance is less than a predetermined threshold value.

6. The electrical leakage detection device according to claim 4, wherein the control unit is configured to determine the diagnostic voltage indicating the location of electrical leakage between the battery and the chassis using the following equation 2:

[ formula 2]

Wherein, V_AIs the diagnostic voltage.

7. An electric leakage detection apparatus for a battery included in an electric vehicle, the electric leakage detection apparatus comprising:

a first switch connected between the second node and a first node connected to a negative terminal of the battery;

a second switch connected between a fourth node and a third node connected to a positive terminal of the battery;

a first resistor connected between the second node and a fifth node connected to a chassis of the electric vehicle;

a second resistor connected between the fourth node and the fifth node;

a first capacitor connected between the sixth node and the seventh node;

a second capacitor connected between the eighth node and the ninth node;

a first switching circuit arranged to selectively connect the first resistor in parallel with the first capacitor;

a second switching circuit arranged to selectively connect the second resistor in parallel with the second capacitor;

a third switching circuit arranged to selectively connect the first capacitor between the first node and a tenth node;

a fourth switching circuit arranged to selectively connect the second capacitor between the first node and an eleventh node;

an analog-to-digital converter (ADC) configured to generate a first digital signal indicative of a voltage between the first node and the tenth node and a second digital signal indicative of a voltage between the first node and the eleventh node; and

a control unit operably coupled to the ADC,

wherein the control unit is configured to:

performing a first switching mode during a first period in which the control unit controls the first switch to an on state, controls the second switch to an off state, controls the first switching circuit to an on state, controls the second switching circuit to an off state, and controls the third switching circuit to an off state,

performing a second switching mode during a second period when the first switching mode ends, in which the control unit controls the first switching circuit to an off state and controls the third switching circuit to an on state,

determining a first voltage indicative of a voltage of the first resistor based on the first digital signal generated within the second period,

performing a third switching mode during a third period, in which the control unit controls the first switch to be in an off state, controls the second switch to be in an on state, controls the first switch circuit to be in an off state, controls the second switch circuit to be in an on state, and controls the fourth switch circuit to be in an off state,

performing a fourth switching mode during a fourth period when the third switching mode ends, in which the control unit controls the second switching circuit to an off state and controls the fourth switching circuit to an on state,

determining a second voltage indicative of a voltage of the second resistor based on the second digital signal generated during the fourth time period, and

determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

8. The electrical leakage detection apparatus according to claim 7, wherein,

the first switching circuit includes:

a third switch electrically connected between the second node and the sixth node; and

a fourth switch electrically connected between the fifth node and the seventh node,

the second switching circuit includes:

a fifth switch electrically connected between the fifth node and the eighth node; and

a sixth switch electrically connected between the fourth node and the ninth node,

the third switching circuit includes:

a seventh switch electrically connected between the sixth node and the first node; and

an eighth switch electrically connected between the seventh node and the tenth node, and

the fourth switching circuit includes:

a ninth switch electrically connected between the fifth node and the eighth node; and

a tenth switch electrically connected between the fourth node and the eleventh node.

9. The electrical leakage detection device according to claim 7, further comprising:

a third resistor electrically connected in series with the first switch between the first node and the second node; and

a fourth resistor electrically connected in series with the second switch between the third node and the fourth node.

10. The electrical leakage detection device according to claim 9, wherein the resistance of the first resistor is equal to the resistance of the second resistor, and

the resistance of the third resistor is equal to the resistance of the fourth resistor,

wherein the control unit is configured to determine an insulation resistance indicating an insulation state between the battery and the chassis using the following equation 3:

[ formula 3]

Wherein, V₁Is said first voltage, V₂Is said second voltage, R₁Is the resistance of the first resistor, R₃Is the resistance of the third resistor, and V_BattIs the voltage of the battery.

11. The electrical leakage detection apparatus according to claim 10, wherein the control unit is configured to determine that electrical leakage between the battery and the chassis occurs when the insulation resistance is less than a predetermined threshold value.

12. The electrical leakage detection device according to claim 10, wherein the control unit is configured to determine the diagnostic voltage indicating the location of electrical leakage between the battery and the chassis using the following equation 4:

[ formula 4]

Wherein, V_AIs the diagnostic voltage.

13. An electric vehicle comprising the electric leakage detection apparatus according to any one of claims 1 to 12.

14. An electrical leakage detection method executable by the electrical leakage detection apparatus according to any one of claims 1 to 6, the electrical leakage detection method comprising the steps of:

executing a first switching mode for controlling the first switch to an on state, the second switch to an off state, the first switching circuit to an on state, the second switching circuit to an off state, and the third switching circuit to an off state during a first period;

performing a second switching mode during a second period when the first switching mode ends, the second switching mode being for controlling the first switching circuit to an off state, controlling the second switching circuit to an off state, and controlling the third switching circuit to an on state;

determining a first voltage indicative of a voltage of the first resistor at a first point in time within the second period based on a digital signal generated by the ADC at the first point in time;

performing a third switching mode during a third period, the third switching mode being for controlling the first switch to an off state, controlling the second switch to an on state, controlling the first switch circuit to an off state, controlling the second switch circuit to an on state, and controlling the third switch circuit to an off state;

executing the second switching mode during a fourth period when the third switching mode ends, the second switching mode being for controlling the first switching circuit to an off state, controlling the second switching circuit to an off state, and controlling the third switching circuit to an on state;

determining a second voltage indicative of a voltage of the second resistor at a second point in time within the fourth period based on a digital signal generated by the ADC at the second point in time; and

determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

15. An electrical leakage detection method executable by the electrical leakage detection apparatus according to any one of claims 7 to 12, the electrical leakage detection method comprising the steps of:

executing a first switching mode for controlling the first switch to an on state, the second switch to an off state, the first switching circuit to an on state, the second switching circuit to an off state, and the third switching circuit to an off state during a first period;

performing a second switching mode during a second period when the first switching mode ends, the second switching mode being for controlling the first switching circuit to an off state and controlling the third switching circuit to an on state;

determining, based on a first digital signal generated at a first point in time within the second period, a first voltage indicative of a voltage of the first resistor at the first point in time;

performing a third switching mode during a third period, the third switching mode being for controlling the first switch to an off state, the second switch to an on state, the first switching circuit to an off state, the second switching circuit to an on state, and the fourth switching circuit to an off state;

when the third switching mode ends, performing a fourth switching mode during a fourth period of time, the fourth switching mode being used to control the second switching circuit to an off state and the fourth switching circuit to an on state;

determining a second voltage indicative of a voltage of the second resistor at a second point in time within the fourth period of time based on a second digital signal generated at the second point in time; and

determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

Technical Field

The present disclosure relates to techniques for detecting electrical leakage between a battery and a chassis.

The present application claims priority to korean patent application No.10-2019-0135660, filed in korea at 29.10.2019, korean patent application No.10-2019-0135661, filed in korea at 29.10.2019, and korean patent application No.10-2020-0127292, filed in korea at 29.9.2020, the disclosures of which are incorporated herein by reference.

Background

Recently, the demand for portable electronic products such as laptop computers, video cameras, and mobile phones has been sharply increased, and with the great development of electric vehicles, energy storage batteries, robots, and satellites, much research is being conducted on high-performance batteries that can be repeatedly recharged.

Currently, commercially available batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, lithium batteries, etc., and among them, lithium batteries have little or no memory effect, so they gain much attention over nickel-based batteries because of their advantages of being rechargeable whenever convenient, having a very low self-discharge rate, and having a high energy density.

Further, in some cases, the battery includes a single rechargeable cell, but in many cases, a plurality of batteries are connected in series and/or parallel to supply a high voltage.

A battery implemented to supply a high voltage needs to be maintained in a state of complete electrical insulation from a chassis of an electric vehicle. When insulation damage (i.e., leakage of electricity) occurs between at least one of the positive terminal or the negative terminal of the battery and the chassis, a flow path of leakage current is formed between the battery and the chassis, thereby causing a failure or malfunction of an electronic device connected to the battery, particularly an accident such as an electric shock.

In order to detect the leakage of the battery, it is necessary to measure the voltage between at least two nodes electrically connected to the battery using a voltage detection device. The related art including patent document 1 uses the chassis as a ground (an electrical position as a reference for voltage measurement) to sample a voltage value required for determining leakage. Therefore, when the negative terminal of the battery is used instead of the chassis as the ground, it is difficult to apply the technique of patent document 1.

Further, the related art detects only the leakage of electricity of the battery, but cannot provide information to a user as to which portion of the battery is in a poor insulation state.

(patent document 1) KR 10-2015-0081988A (published in 2015, 7 months and 15 days)

Disclosure of Invention

Technical problem

The present disclosure is designed to solve the above-described problems, and therefore aims to provide a leakage detecting device, a leakage detecting method, and an electric vehicle including the leakage detecting device, which use a negative terminal of a battery instead of a chassis as a ground for detecting a voltage required for leakage detection.

The present disclosure is also directed to providing a leakage detecting device, a leakage detecting method, and an electric vehicle including the leakage detecting device that determine a location of leakage in a battery when leakage of the battery is detected.

These and other objects and advantages of the present disclosure will be understood from the following description, and will be apparent from the embodiments of the present disclosure. Further, it will be readily understood that the objects and advantages of the present disclosure may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

Technical scheme

An electrical leakage detection apparatus for a battery included in an electric vehicle according to a first embodiment of the present disclosure includes: a first switch connected between the second node and a first node connected to a negative terminal of the battery; a second switch connected between a fourth node and a third node connected to a positive terminal of the battery; a first resistor connected between the second node and a fifth node connected to a chassis of the electric vehicle; a second resistor electrically connected between the fourth node and the fifth node; a capacitor connected between the sixth node and the seventh node; a first switching circuit configured to selectively connect the first resistor in parallel with the capacitor; a second switching circuit configured to selectively connect the second resistor in parallel with the capacitor; a third switching circuit arranged to selectively connect the capacitor between the first node and the eighth node; an analog-to-digital converter (ADC) configured to generate a digital signal indicative of a voltage between the first node and the eighth node; and a control unit operatively coupled to the ADC. The control unit is configured to execute a first switching mode during a first period, in which the control unit controls the first switch to be in an on state, controls the second switch to be in an off state, controls the first switching circuit to be in an on state, controls the second switching circuit to be in an off state, and controls the third switching circuit to be in an off state. When the first switching mode ends, the control unit is configured to execute a second switching mode during a second period, in which the control unit controls the first switching circuit to be in an off state, controls the second switching circuit to be in an off state, and controls the third switching circuit to be in an on state. The control unit is configured to determine a first voltage indicative of a voltage of the first resistor based on a digital signal generated by the analog-to-digital converter during the second period. The control unit is configured to execute a third switching mode during a third period, in which the control unit controls the first switch to be in an off state, controls the second switch to be in an on state, controls the first switch circuit to be in an off state, controls the second switch circuit to be in an on state, and controls the third switch circuit to be in an off state. When the third switching mode ends, the control unit is configured to execute the second switching mode during a fourth period, in which the control unit controls the first switching circuit to an off state, controls the second switching circuit to an off state, and controls the third switching circuit to an on state. The control unit is configured to determine a second voltage indicative of a voltage of the second resistor based on a digital signal generated by the analog-to-digital converter during the fourth time period. The control unit is configured to determine whether or not electric leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

The first switching circuit includes: a third switch connected between the second node and the sixth node; and a fourth switch connected between the fifth node and the seventh node. The second switching circuit includes: a fifth switch connected between the fifth node and the sixth node; and a sixth switch connected between the fourth node and the seventh node. The third switching circuit includes: a seventh switch connected between the sixth node and the first node; and an eighth switch connected between the seventh node and the eighth node.

The electric leakage detection apparatus may further include: a third resistor electrically connected in series with the first switch between the first node and the second node; and a fourth resistor electrically connected in series with the second switch between the third node and the fourth node.

The resistance of the first resistor may be equal to the resistance of the second resistor. The resistance of the third resistor may be equal to the resistance of the fourth resistor. The control unit may be configured to determine an insulation resistance indicating an insulation state between the battery and the chassis using the following equation 1:

[ formula 1]

Wherein, V₁Is said first voltage, V₂Is said second voltage, R₁Is the resistance of the first resistor, R₃Is the resistance of the third resistor, and V_BattIs the voltage of the battery.

The control unit may be configured to determine an electric leakage between the battery and the chassis occurring when the insulation resistance is less than a predetermined threshold value.

The control unit may be configured to determine a diagnostic voltage indicative of a location of electrical leakage between the battery and the chassis using equation 2 below:

[ formula 2]

Wherein, V_AIs the diagnostic voltage.

A leakage detecting device for a battery included in an electric vehicle according to a second embodiment of the present disclosure includes: a first switch connected between the second node and a first node connected to a negative terminal of the battery; a second switch connected between a fourth node and a third node connected to a positive terminal of the battery; a first resistor connected between the second node and a fifth node connected to a chassis of the electric vehicle; a second resistor connected between the fourth node and the fifth node; a first capacitor connected between the sixth node and the seventh node; a second capacitor connected between the eighth node and the ninth node; a first switching circuit arranged to selectively connect the first resistor in parallel with the first capacitor; a second switching circuit arranged to selectively connect the second resistor in parallel with the second capacitor; a third switching circuit arranged to selectively connect the first capacitor between the first node and a tenth node; a fourth switching circuit arranged to selectively connect the second capacitor between the first node and an eleventh node; an ADC configured to generate a first digital signal indicative of a voltage between the first node and the tenth node and a second digital signal indicative of a voltage between the first node and the eleventh node; and a control unit operatively coupled to the ADC. The control unit is configured to execute a first switching mode during a first period, in which the control unit controls the first switch to be in an on state, controls the second switch to be in an off state, controls the first switching circuit to be in an on state, controls the second switching circuit to be in an off state, and controls the third switching circuit to be in an off state. When the first switching mode ends, the control unit is configured to perform a second switching mode during a second period in which the control unit controls the first switching circuit to an off state and controls the third switching circuit to an on state. The control unit is configured to determine a first voltage indicative of a voltage of the first resistor based on the first digital signal generated within the second period. The control unit is configured to execute a third switching mode during a third period, in which the control unit controls the first switch to be in an off state, controls the second switch to be in an on state, controls the first switch circuit to be in an off state, controls the second switch circuit to be in an on state, and controls the fourth switch circuit to be in an off state. When the third switching mode ends, the control unit is configured to execute a fourth switching mode during a fourth period of time in which the control unit controls the second switching circuit to an off state and controls the fourth switching circuit to an on state. The control unit is configured to determine a second voltage indicative of a voltage of the second resistor based on the second digital signal generated within the fourth time period. The control unit is configured to determine whether or not electric leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

The first switching circuit includes: a third switch electrically connected between the second node and the sixth node; and a fourth switch electrically connected between the fifth node and the seventh node. The second switching circuit includes: a fifth switch electrically connected between the fifth node and the eighth node; and a sixth switch electrically connected between the fourth node and the ninth node. The third switching circuit includes: a seventh switch electrically connected between the sixth node and the first node; and an eighth switch electrically connected between the seventh node and the tenth node. The fourth switching circuit includes: a ninth switch electrically connected between the fifth node and the eighth node; and a tenth switch electrically connected between the fourth node and the eleventh node.

The electric leakage detection apparatus may further include: a third resistor electrically connected in series with the first switch between the first node and the second node; and a fourth resistor electrically connected in series with the second switch between the third node and the fourth node.

The resistance of the first resistor may be equal to the resistance of the second resistor. The resistance of the third resistor may be equal to the resistance of the fourth resistor. The control unit may be configured to determine an insulation resistance indicating an insulation state between the battery and the chassis using the following equation 3:

[ formula 3]

Wherein, V₁Is said first voltage, V₂Is said second voltage, R₁Is the resistance of the first resistor, R₃Is the resistance of the third resistor, and V_BattIs the voltage of the battery.

The control unit may be configured to determine an electric leakage between the battery and the chassis occurring when the insulation resistance is less than a predetermined threshold value.

The control unit may be configured to determine a diagnostic voltage indicating a location of electrical leakage between the battery and the chassis using equation 4 below:

[ formula 4]

Wherein, V_AIs the diagnostic voltage.

An electric vehicle according to another aspect of the present disclosure includes the electric leakage detecting device according to the first embodiment or the second embodiment.

An electrical leakage detection method according to still another aspect of the present disclosure, which can be performed by the electrical leakage detection apparatus according to the first embodiment, includes: executing a first switching mode for controlling the first switch to an on state, the second switch to an off state, the first switching circuit to an on state, the second switching circuit to an off state, and the third switching circuit to an off state during a first period; performing a second switching mode during a second period when the first switching mode ends, the second switching mode being for controlling the first switching circuit to an off state, controlling the second switching circuit to an off state, and controlling the third switching circuit to an on state; determining a first voltage indicative of a voltage of the first resistor at a first point in time within the second period based on a digital signal generated by the ADC at the first point in time; performing a third switching mode during a third period, the third switching mode being for controlling the first switch to an off state, controlling the second switch to an on state, controlling the first switch circuit to an off state, controlling the second switch circuit to an on state, and controlling the third switch circuit to an off state; executing the second switching mode during a fourth period when the third switching mode ends, the second switching mode being for controlling the first switching circuit to an off state, controlling the second switching circuit to an off state, and controlling the third switching circuit to an on state; determining a first voltage indicative of a voltage of the second resistor at a second point in time within the fourth period based on a digital signal generated by the ADC at the second point in time; and determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

An electrical leakage detection method according to still another aspect of the present disclosure, which can be performed by the electrical leakage detection apparatus according to the second embodiment, includes: executing a first switching mode for controlling the first switch to an on state, the second switch to an off state, the first switching circuit to an on state, the second switching circuit to an off state, and the third switching circuit to an off state during a first period; performing a second switching mode during a second period when the first switching mode ends, the second switching mode being for controlling the first switching circuit to an off state and controlling the third switching circuit to an on state; determining, based on a first digital signal generated at a first point in time within the second period, a first voltage indicative of a voltage of the first resistor at the first point in time; performing a third switching mode during a third period, the third switching mode being for controlling the first switch to an off state, the second switch to an on state, the first switching circuit to an off state, the second switching circuit to an on state, and the fourth switching circuit to an off state; when the third switching mode ends, performing a fourth switching mode during a fourth period of time, the fourth switching mode being used to control the second switching circuit to an off state and the fourth switching circuit to an on state; determining a second voltage indicative of a voltage of the second resistor at a second point in time within the fourth period of time based on a second digital signal generated at the second point in time; and determining whether leakage occurs between the battery and the chassis based on the first voltage and the second voltage.

Advantageous effects

According to at least one of the embodiments of the present disclosure, electric leakage between the battery and the chassis may be detected using a negative terminal of the battery instead of the chassis as a ground for detecting a voltage required for electric leakage detection.

In addition, according to at least one of the embodiments of the present disclosure, when the electric leakage of the battery is detected, a position of the electric leakage in the battery may be determined.

The effects of the present disclosure are not limited to the above-mentioned effects, and those effects and other effects will be clearly understood by those skilled in the art from the appended claims.

Drawings

The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the detailed description of the disclosure given below, serve to provide a further understanding of the technical aspects of the disclosure, and therefore, the disclosure should not be construed as being limited to the accompanying drawings.

Fig. 1 is a diagram exemplarily showing a configuration of an electric vehicle including a leakage detecting device according to a first embodiment of the present disclosure.

Fig. 2 is a diagram exemplarily showing a configuration of an electric vehicle including a leakage detecting device according to a second embodiment of the present disclosure.

Fig. 3 is a flowchart exemplarily illustrating an electrical leakage detection method that can be performed by the electrical leakage detection apparatus according to the first embodiment as illustrated in fig. 1.

Fig. 4 is a flowchart exemplarily illustrating an electrical leakage detection method that can be performed by the electrical leakage detection apparatus according to the second embodiment as illustrated in fig. 2.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description is made, it should be understood that the terms or words used in the specification and the appended claims should not be construed as limited to general or dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is able to define terms appropriate for the best explanation.

Therefore, the embodiments described herein and the illustrations shown in the drawings are only the most preferred embodiments of the present disclosure and are not intended to fully describe the technical aspects of the present disclosure, so it should be understood that various other equivalents and modifications thereof can be made at the time of filing this application.

Terms including ordinal numbers such as "first," "second," etc., are used to distinguish one element from another element, but are not intended to limit the elements by the terms.

Unless the context clearly dictates otherwise, it should be understood that the term "comprising" when used in this specification is taken to specify the presence of stated elements but does not preclude the presence or addition of one or more other elements. In addition, the term "control unit" as used herein refers to at least one functional or operational processing unit, and this may be implemented in hardware or software, alone or in combination.

In addition, throughout the specification, it will also be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present.

Fig. 1 is a diagram exemplarily showing a configuration of an electric vehicle including a leakage detecting device according to a first embodiment of the present disclosure.

Referring to fig. 1, an electric vehicle 1 includes a chassis 2, an inverter 3, an electric motor 4, a battery 10, and a leakage detecting apparatus 100. For convenience of description, illustration of a relay that opens and closes the power path between the battery 10 and the inverter 3 is omitted.

The inverter 3 is provided to convert Direct Current (DC) from the battery into Alternating Current (AC) in response to a command from the electrical leakage detection apparatus 100. The electric motor 4 is a three-phase AC motor and is operated with AC generated by the inverter 3. The electric vehicle 1 runs by the driving power generated during the operation of the electric motor 4.

The battery 10 includes a negative terminal P connected in series₁And a positive terminal P₂A plurality of battery cells B in between₁-B_n. n is a natural number of 2 or more. i is a natural number from 1 to (n-1). Multiple battery cores B₁-B_nRechargeable battery cells, such as lithium ion cells, may be included and are not limited to a particular type. When x and y are natural numbers and x is more than or equal to 1<When y is less than or equal to n, the battery cell B_xCan be arranged at the specific battery cell B_yFurther downstream, battery cell B_yCan be arranged at the specific battery cell B_xThe more upstream side. Negative terminal P₁May be a battery cell B₁To the negative terminal of (a). Positive terminal P₂May be a battery cell B_nThe positive terminal of (1).

The electric leakage detecting device 100 is provided to be electrically connected to the negative terminal P₁Positive terminal P₂And a chassis 2.

R shown in FIG. 1_LeakIs a virtual resistance (hereinafter referred to as "insulation resistance") indicating the degree of insulation of the battery 10 from the chassis 2. When no leakage occurs in the battery 10, the insulation resistance R_LeakWith very large values exceeding a predetermined threshold. In contrast, when a short circuit is formed between a specific position (e.g., "11", "12", or "B") of the battery 10 and the chassis 2 due to moisture permeation from the outside or water leakage in the battery 10 (i.e., when electric leakage occurs in the battery 10), the insulation resistance R_LeakWill have a very small value equal to or less than the threshold value. Here, the threshold value may be a preset value to prevent an electric shock accident.

The leakage detecting apparatus 100 includes first to eighth nodes N1, N2, N3, N4, N5, N6, N7, N8, a first resistor 11, a second resistor 12, a first switch 21, a second switch 22, a capacitor C, a first switch circuit 110, a second switch circuit 120, a third switch circuit 130, an analog-to-digital converter (ADC)150, and a control unit 160. The electrical leakage detection device 100 may further include a third resistor 13 and a fourth resistor 14.

The first to eighth nodes N1-N8 may be portions of conductors such as bus bars or wires for making electrical connections between the components of the electrical leakage detection apparatus 100 and the battery 10 and the chassis 2.

The first switch 21 is electrically connected toA node N1 and a second node N2. The first node N1 has a negative terminal P connected to the battery 10₁The same potential. The third resistor 13 may be electrically connected in series with the first switch 21 between the first node N1 and the second node N2. That is, one end of the third resistor 13 and one end of the first switch 21 are commonly connected, any one of the other end of the third resistor 13 and the other end of the first switch 21 is electrically connected to the first node N1, and the other is electrically connected to the second node N2. The third resistor 13 is provided to prevent a surge current when the first switch 21 is controlled to be in an ON (ON) state. In response to a first switching signal S from the control unit 160₁And controls the first switch 21 to be in an on state, the first node N1 is electrically connected to the fifth node N5 through the first switch 21, the third resistor 13, and the first resistor 11.

The second switch 22 is electrically connected between the third node N3 and the fourth node N4. The third node N3 has the same potential as the positive terminal of the battery 10. The fourth resistor 14 may be electrically connected in series with the second switch 22 between the third node N3 and a fourth node N4. That is, one end of the fourth resistor 14 and one end of the second switch 22 are commonly connected, any one of the other end of the fourth resistor 14 and the other end of the second switch 22 is electrically connected to the third node N3, and the other is electrically connected to the fourth node N4. The fourth resistor 14 is provided to prevent an inrush current when the second switch 22 is controlled to the on state. The resistance of the third resistor 13 may be equal to the resistance of the fourth resistor 14. In response to a second switching signal S from the control unit 160₂And controls the second switch 22 to be in an on state, the third node N3 is electrically connected to the fifth node N5 through the second switch 22, the fourth resistor 14, and the second resistor 12.

The first resistor 11 is electrically connected between the second node N2 and the fifth node N5. The fifth node N5 is a node that is electrically connected to the chassis 2 of the electric vehicle 1 and has the same potential as the chassis 2.

The second resistor 12 is electrically connected between the fourth node N4 and the fifth node N5. That is, the first resistor 11 and the second resistor 12 are electrically connected in series through the fifth node N5 between the second node N2 and the fourth node N4.

The resistance of the first resistor 11 may be equal to the resistance of the second resistor 12. The resistance of the third resistor 13 may be several times to several hundred times the resistance of the first resistor 11.

The first switch circuit 110 is provided to selectively electrically connect the first resistor 11 in parallel with the capacitor C. The first switching circuit 110 may include a third switch 111 and a fourth switch 112. The third switch 111 is electrically connected between the second node N2 and a sixth node N6. The fourth switch 112 is electrically connected between the fifth node N5 and the seventh node N7. The first switch circuit 110 being in an on state indicates that each of the third switch 111 and the fourth switch 112 is responsive to the third switch signal S₃And a fourth switching signal S₄But is in the on state. The first switch circuit 110 being in an Open (OFF) state indicates that at least one of the third switch 111 or the fourth switch 112 is in an open state. When the first switching circuit 110 is in an on state, the first resistor 11 is electrically connected in parallel with the capacitor C, and thus a voltage equal to the voltage applied to the first resistor 11 is charged at both ends of the capacitor C.

The second switch circuit 120 is provided to selectively electrically connect the second resistor 12 in parallel with the capacitor C. The second switching circuit 120 may include a fifth switch 121 and a sixth switch 122. The fifth switch 121 is electrically connected between the fifth node N5 and the sixth node N6. The sixth switch 122 is electrically connected between the fourth node N4 and the seventh node N7. The second switch circuit 120 being in the on state indicates that the fifth switch 121 and the sixth switch 122 are respectively responsive to the fifth switch signal S₅And a sixth switching signal S₆But is in the on state. The second switch circuit 120 being in the off state indicates that at least one of the fifth switch 121 or the sixth switch 122 is in the off state. When the second switching circuit 120 is in an on state, the second resistor 12 is electrically connected in parallel with the capacitor C, and thus a voltage equal to the voltage applied to the second resistor 12 is charged at both ends of the capacitor C.

The third switching circuit 130 is provided to selectively electrically connect the capacitor C between the first node N1 and the eighth node N8. The third switching circuit 130 may include a seventh switch 131 and an eighth switchAnd (7) closing 132. The seventh switch 131 is electrically connected between the sixth node N6 and the first node N1. The eighth switch 132 is electrically connected between the seventh node N7 and the eighth node N8. The third switch circuit 130 being in the on state indicates that the seventh switch 131 and the eighth switch 132 are respectively responsive to the seventh switch signal S₇And an eighth switching signal S₈But is in the on state. The third switch circuit 130 being in the open state indicates that at least one of the seventh switch 131 or the eighth switch 132 is in the open state. When the third switching circuit 130 is in an on state, the capacitor C is electrically connected in parallel between the first node N1 and the eighth node N8, and thus a voltage equal to a voltage applied to the capacitor C is provided as an input of the ADC 150.

The first switch 21, the second switch 22, the third switch 111, the fourth switch 112, the fifth switch 121, the sixth switch 122, the seventh switch 131, and the eighth switch 132 may be known switching devices such as Metal Oxide Semiconductor Field Effect Transistors (MOSFETs).

ADC150 is connected via a pair of input terminals I₁、I₂Is electrically connected to the first node N1 and the eighth node N8. That is, one input terminal is electrically connected to the first node N1, and the other input terminal is electrically connected to the eighth node N8. The ADC150 is configured to use a transistor having a negative terminal P₁The first node N1 of the same potential serves as a ground, generating a digital signal indicating a voltage between the first node N1 and the eighth node N8, which are supplied as input voltages.

The control unit 160 may be implemented in hardware using at least one of an Application Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Digital Signal Processing Device (DSPD), a Programmable Logic Device (PLD), a Field Programmable Gate Array (FPGA), a microprocessor, or an electrical unit performing other functions. The control unit 160 may include a memory built therein. The memory may store programs and data necessary to perform the methods described below. The memory may include a storage medium of at least one type, for example, a flash memory type, a hard disk type, a Solid State Disk (SSD) type, a Silicon Disk Drive (SDD) type, a multimedia card micro type, a Random Access Memory (RAM), a Static Random Access Memory (SRAM), a Read Only Memory (ROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), or a Programmable Read Only Memory (PROM).

The control unit 160 is operatively coupled to the inverter 3, the first switch 21, the second switch 22, the first switch circuit 110, the second switch circuit 120, the third switch circuit 130, and the ADC 150. The control unit 160 may selectively output first to eighth switching signals S₁-S₈To independently control the first switch 21, the second switch 22, the first switch circuit 110, the second switch circuit 120, and the third switch circuit 130. That is, each of the first switch 21, the second switch 22, the first switch circuit 110, the second switch circuit 120, and the third switch circuit 130 may be controlled to be in an on or off state.

A value indicating the resistance of each of the first resistor 11, the second resistor 12, the third resistor 13, and the fourth resistor 14 is prestored in the memory.

When the first switch 21 has the on state, the ratio of the voltage of the first resistor 11 to the voltage between the first node N1 and the fifth node N5 is equal to the ratio of the resistance of the first resistor 11 to the sum of the resistances of the first resistor 11 and the third resistor 13. For example, when the voltage between the first node N1 and the fifth node N5 is 200V, the resistance of the third resistor 13 is 5.98M Ω, and the resistance of the first resistor 11 is 0.02M Ω, the voltage of the first resistor 11 is 200 × 0.02/(5.98+0.02) V.

When the second switch 22 has the on state, the ratio of the voltage of the second resistor 12 to the voltage between the third node N3 and the fifth node N5 is equal to the ratio of the resistance of the second resistor 12 to the sum of the resistances of the second resistor 12 and the fourth resistor 14.

When the control unit 160 is executing the first switching mode, the control unit 160 controls the first switch 21 to be in the on state, controls the second switch 22 to be in the off state, controls the first switching circuit 110 to be in the on state, controls the second switching circuit 120 to be in the off state, and controls the third switching circuit 130 to be in the off state.

When the control unit 160 is executing the second switching mode, the control unit 160 controls the first switching circuit 110 to be in the off state, controls the second switching circuit 120 to be in the off state, and controls the third switching circuit 110 to be in the on state. In the second switching mode, the first switch 21 and the second switch 22 may be controlled to be in an off state.

When the control unit 160 is executing the third switching mode, the control unit 160 controls the first switch 21 to be in the off state, controls the second switch 22 to be in the on state, controls the first switching circuit 110 to be in the off state, controls the second switching circuit 120 to be in the on state, and controls the third switching circuit 130 to be in the off state.

The control unit 160 may perform the first switching mode during a first period and then perform the second switching mode during a second period. The control unit 160 may determine the first voltage based on the digital signal generated by the ADC150 at the first time point within the second period. The first voltage is indicative of the voltage across the first resistor 11 at a first point in time.

The control unit 160 may perform the third switching mode during the third period and then perform the second switching mode during the fourth period. The control unit 160 may determine the second voltage based on the digital signal generated by the ADC150 at the second time point within the fourth period. The second voltage is indicative of the voltage across the second resistor 12 at the second point in time.

Before or after determining the first voltage and the second voltage, the control unit 160 may determine the voltage of the battery 10 by performing the fourth switching mode during the fifth period and then performing the second switching mode during the sixth period. When the control unit 160 executes the fourth switching mode, the control unit 160 controls the first switch 21 to be in the on state, controls the second switch 22 to be in the on state, controls the first switching circuit 110 to be in the on state, controls the second switching circuit 120 to be in the off state, and controls the third switching circuit 130 to be in the off state. The control unit 160 may determine the voltage of the battery 10 based on the digital signal generated by the ADC150 at the third time point within the sixth period. For example, the digital signal at the third time point indicates that the voltage of the capacitor C is 10V when the resistances of the first to fourth resistors 11, 12, 13, 14 are R, respectively₁、R₁、R₃、R₃Then, the voltage of the battery 10 is {2 (R) }₁+R₃)}/R₁×10V。

Alternatively, the control unit 160 may use a plurality of battery cells B before or after determining the first and second voltages₁-B_nIs included in the electric leakage detection apparatus 100 to measure a plurality of battery cells B₁-B_nAnd the voltage of the battery 10 (hereinafter referred to as "V_Batt”)。

The duration of each of the first period, the second period, the third period, the fourth period, the fifth period, and the sixth period may be preset. In addition, a time difference between a start time of the earliest period and an end time of the latest period among the first period, the second period, the third period, the fourth period, the fifth period, and the sixth period may be equal to or less than a preset diagnosis execution time.

As shown in fig. 1, assume a battery cell B_iAnd battery core B_i+1At the point of connection P between_LeakElectrically short-circuited to the chassis 2. Connection point P_LeakMay be a location of electrical leakage between the battery 10 and the chassis 2. Battery cell B_iAnd battery core B_i+1At the point of connection P between_LeakIs a battery cell B_iPositive terminal and battery cell B_i+1Is connected to the negative terminal of the switch.

When the voltage of the first resistor 11 is equal to the voltage of the capacitor C while the control unit 160 is performing the first switching mode, the voltage of the second resistor is equal to the voltage of the capacitor C_LeakInsulation resistance R_LeakA chassis 2, a first resistor 11, a first switch 21, a third resistor 13, a negative terminal P₁And battery cell B₁-B_iForming a closed loop circuit.

The voltage across the first switch 21 is negligibly low. Thus, the connection point P_LeakAnd a negative terminal P₁Voltage V between_AInsulation resistance R_LeakAnd the first voltage have a relationship of the following formula 1.

[ formula 1]

When the voltage of the second resistor 12 is equal to the voltage of the capacitor C when the control unit 160 is performing the third switching mode, the voltage of the second resistor is controlled by the positive terminal P₂A fourth resistor 14, a second switch 22, a second resistor 12, a chassis 2, an insulation resistor R_LeakConnection point P_LeakAnd battery cell B_i+1-B_nForming a closed loop circuit.

The voltage across the second switch 22 is negligibly low. Therefore, when the resistance of the first resistor 11 is equal to the resistance of the second resistor 12 and the resistance of the third resistor 13 is equal to the resistance of the fourth resistor 14, the positive terminal P₂And a connection point P_LeakVoltage V between_BInsulation resistance R_LeakAnd the second voltage has a relationship of the following formula 2.

[ formula 2]

In formulas 1 and 2, V₁Is a first voltage, V₂Is a second voltage, R₁Is the resistance of the first resistor 11, R₃Is the resistance of the third resistor 13.

In formula 1 and formula 2, only V_a、V_bAnd R_LeakIs unknown. When the voltage across the battery 10 is V_BattWhen, V_Batt＝V_A+V_B. Therefore, the following formulas 3 to 5 are derived from formulas 1 and 2.

[ formula 3]

[ formula 4]

[ formula 5]

When the insulation resistance R_LeakBelow a predetermined threshold, the control unit 160 may determine that electric leakage occurs between the battery 10 and the chassis 2, and generate an electric leakage alarm signal.

In the formulas 4 and 5, the voltage V_AAnd voltage V_BIndicates the location of the electrical leakage of the battery 10 relative to the chassis 2 and may be referred to as a "first diagnostic voltage" and a "second diagnostic voltage", respectively.

When the first diagnostic voltage V_AIs equal to or higher than the first to i-th battery cells B₁-B_iIs less than the sum of the voltages of the first to i +1 th battery cells B₁-B_i+1May determine battery cell B when the voltages of the battery cells are summed_iAnd battery core B_i+1At the point of connection P between_LeakIs the leakage location.

When the second diagnostic voltage V_BIs equal to or higher than the i +1 th to n-th battery cells B_i+1-B_nIs less than the sum of the voltages of the i-th to n-th battery cells B_i-B_nMay determine battery cell B when the voltages of the battery cells are summed_iAnd battery core B_i+1At the point of connection P between_LeakIs the leakage location.

When the first diagnostic voltage V_AIs 0V and the second diagnostic voltage V_BAbove 0V, the control unit 160 may determine the negative terminal P₁Is the leakage location. When the first diagnostic voltage V_AHigher than 0V and a second diagnostic voltage V_BAt 0V, the control unit 160 may determine the positive terminal P₂Is the leakage location. When the first diagnostic voltage V_AIs 0V and the second diagnostic voltage V_BAt 0V, the control unit 160 may determine that the electrical leakage detection apparatus 100 is malfunctioning.

The electrical leakage detection apparatus 100 may further include an interface unit 170. The interface unit 170 may include at least one of a display or a speaker to output the leakage warning signal from the control unit 160 as a signal in a format that can be recognized by a user. The electrical leakage warning signal may include information indicating the location of the electrical leakage.

Fig. 2 is a diagram exemplarily showing a configuration of an electric vehicle including a leakage detecting device according to a second embodiment of the present disclosure. The chassis 2, the inverter 3, the electric motor 4, and the battery 10 shown in fig. 2 are the same as those described with reference to fig. 1, and redundant description is omitted herein.

Using two capacitors C according to the second embodiment₁、C₂Measuring voltage value V required for leakage detection₁、V₂Is different from the leakage detection apparatus 100 using the single capacitor C according to the first embodiment.

Referring to fig. 2, the leakage detecting apparatus 200 according to the second embodiment includes first to eleventh nodes M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, M11, a first resistor 31, a second resistor 32, a first switch 41, a second switch 42, a first capacitor C1, a second capacitor C2, a first switch circuit 210, a second switch circuit 220, a third switch circuit 230, a fourth switch circuit 240, an ADC 250, and a control unit 260. The electrical leakage detection device 200 may further include a third resistor 33 and a fourth resistor 34.

The first to eleventh nodes M1-M11 may be portions of conductors such as bus bars or wires for making electrical connections between the components of the electrical leakage detecting device 200, the battery 10, and the chassis 2.

The first switch 41 is electrically connected between the first node M1 and the second node M2. The first node M1 has a negative terminal P connected to the battery 10₁The same potential. The third resistor 33 may be electrically connected in series with the first switch 41 between the first node M1 and the second node M2. That is, one end of the third resistor 33 and one end of the first switch 41 are commonly connected, any one of the other end of the third resistor 33 and the other end of the first switch 41 is electrically connected to the first node M1, and the other is electrically connected to the second node M2. The third resistor 33 is provided to prevent an inrush current when the first switch 41 is controlled to the on state.In response to a first switching signal S from the control unit 260₁And controls the first switch 41 to be in an on state, the first node M1 is electrically connected to the fifth node M5 through the first switch 41, the third resistor 33, and the first resistor 31.

The second switch 42 is electrically connected between the third node M3 and the fourth node M4. The third node M3 has a positive terminal P with the battery 10₂The same potential. The fourth resistor 34 may be electrically connected in series with the second switch 42 between the third node M3 and the fourth node M4. That is, one end of the fourth resistor 34 and one end of the second switch 42 are commonly connected, any one of the other end of the fourth resistor 34 and the other end of the second switch 42 is electrically connected to the third node M3, and the other is electrically connected to the fourth node M4. The fourth resistor 34 is provided to prevent an inrush current when the second switch 42 is controlled to the on state. The resistance of the third resistor 33 may be equal to the resistance of the fourth resistor 34. The third node M3 is electrically connected to the fifth node M5 through the second switch 42, the fourth resistor 34, and the second resistor 32 while controlling the second switch 42 to be in an on state in response to the second switching signal S2 from the control unit 260.

The first resistor 31 is electrically connected between the second node M2 and the fifth node M5. The fifth node M5 is a node that is electrically connected to the chassis 2 of the electric vehicle 1 and has the same potential as the chassis 2.

The second resistor 32 is electrically connected between the fourth node M4 and the fifth node M5. That is, the first resistor 31 and the second resistor 32 are electrically connected in series through the fifth section MN5 between the second node M2 and the fourth node M4.

The resistance of the first resistor 31 may be equal to the resistance of the second resistor 32. The resistance of the third resistor 33 may be several times to several hundred times the resistance of the first resistor 31. A first capacitor C₁May be equal to the second capacitor C₂The capacitance of (c).

The first switch circuit 210 is provided to selectively connect the first resistor 31 and the first capacitor C₁Are electrically connected in parallel. The first switching circuit 210 may include a third switch 211 and a fourth switch 212. The third switch 211 is electrically connected to the second nodePoint M2 and a sixth node M6. The fourth switch 212 is electrically connected between the fifth node M5 and the seventh node M7. The first switching circuit 210 being in an on state indicates that the third switch 211 and the fourth switch 212 are respectively responsive to the third switching signal S₃And a fourth switching signal S₄But is in the on state. The first switch circuit 210 being in an open state indicates that at least one of the third switch 211 or the fourth switch 212 is in an open state. When the first switch circuit 210 is in the on state, the first resistor 31 and the first capacitor C₁Are electrically connected in parallel, so that a voltage equal to the voltage applied to the first resistor 31 is present in the first capacitor C₁Is charged at both ends.

The second switch circuit 220 is configured to selectively couple the second resistor 32 with the second capacitor C₂Are electrically connected in parallel. The second switching circuit 220 may include a fifth switch 221 and a sixth switch 222. The fifth switch 221 is electrically connected between the fifth node M5 and the eighth node M8. The sixth switch 222 is electrically connected between the fourth node M4 and the ninth node M9. The second switching circuit 220 being in an on state indicates that the fifth switch 221 and the sixth switch 222 are respectively responsive to the fifth switching signal S₅And a sixth switching signal S₆But is in the on state. The second switch circuit 220 being in the open state indicates that at least one of the fifth switch 221 or the sixth switch 222 is in the open state. The second resistor 32 and the second capacitor C when the second switch circuit 220 is in the on state₂Are electrically connected in parallel, so that a voltage equal to the voltage applied to the second resistor 32 is present in the second capacitor C₂Is charged at both ends.

The third switching circuit 230 is provided to selectively couple the first capacitor C₁Electrically connected between the first node M1 and a tenth node M10. The third switching circuit 230 may include a seventh switch 231 and an eighth switch 232. The seventh switch 231 is electrically connected between the sixth node M6 and the first node M1. The eighth switch 232 is electrically connected between the seventh node M7 and the tenth node M10. The third switch circuit 230 being in an on state indicates that the seventh switch 231 and the eighth switch 232 are responsive to the seventh switching signal S₇And an eighth switching signal S₈But is in the on state. Third switch circuit230 in the open state indicates that at least one of the seventh switch 231 or the eighth switch 232 is in the open state. When the third switching circuit 230 is in an on state, the first capacitor C₁Is electrically connected in parallel between the first node M1 and the tenth node M10, and thus is applied to the first capacitor C₁Is supplied to a first input of the ADC 250.

The fourth switching circuit 240 is provided to selectively switch the second capacitor C₂Electrically connected between the first node M1 and an eleventh node M11. The fourth switching circuit 240 may include a ninth switch 241 and a tenth switch 242. The ninth switch 241 is electrically connected between the eighth node M8 and the first node M1. The tenth switch 242 is electrically connected between the ninth node M9 and the eleventh node M11. The fourth switching circuit 240 being in the on state indicates that the ninth switch 241 and the tenth switch 242 are respectively responsive to the ninth switching signal S₉And a tenth switching signal S₁₀But is in the on state. The fourth switch circuit 240 being in the open state indicates that at least one of the ninth switch 241 or the tenth switch 242 is in the open state. The second capacitor C is in the on state of the fourth switching circuit 240₂Is electrically connected in parallel between the first node M1 and the eleventh node M11, and thus is applied to the second capacitor C₂Is provided as a second input of the ADC 250.

The first switch 41, the second switch 42, the third switch 211, the fourth switch 212, the fifth switch 221, the sixth switch 222, the seventh switch 231, the eighth switch 232, the ninth switch 241, and the tenth switch 242 may be well-known switching devices such as Metal Oxide Semiconductor Field Effect Transistors (MOSFETs).

ADC 250 includes four input terminals I₁、I₂、I₃、I₄. Input terminal I₁And an input terminal I₃Is electrically connected to the first node M1, the input terminal I₂Is electrically connected to the tenth node M10, and input terminal I₄Is electrically connected to the eleventh node M11. The ADC 250 is configured to use a transistor having a negative terminal P₁The first node M1 of the same potential is taken as the ground, and the indication is selectively generated as the first inputA first digital signal indicating a voltage between the first node M1 and the tenth node M10, and a second digital signal indicating a voltage between the first node M1 and the eleventh node M11, which are provided as second inputs.

The control unit 260 may be configured substantially the same as the control unit 160 shown in fig. 1. The control unit 260 is operatively coupled to the inverter 3, the first switch 41, the second switch 42, the first switch circuit 210, the second switch circuit 220, the third switch circuit 230, the fourth switch circuit 240, and the ADC 250. The control unit 260 may selectively output first to tenth switching signals S₁-S₁₀To independently control the first switch 41, the second switch 42, the first switch circuit 210, the second switch circuit 220, the third switch circuit 230, and the fourth switch circuit 240. That is, each of the first switch 41, the second switch 42, the first switch circuit 210, the second switch circuit 220, the third switch circuit 230, and the fourth switch circuit 240 may be controlled to be in an on state or an off state.

A value indicating the resistance of each of the first resistor 31, the second resistor 32, the third resistor 33, and the fourth resistor 34 may be prestored in the memory. The first resistor 31, the second resistor 32, the first resistor 11 and the second resistor 12 may have equal resistances. The third resistor 33, the fourth resistor 34, the third resistor 13 and the fourth resistor 14 may have equal resistances.

When the first switch 41 has the on state, the ratio of the voltage of the first resistor 31 to the voltage between the first node M1 and the fifth node M5 is equal to the ratio of the resistance of the first resistor 31 to the sum of the resistances of the first resistor 31 and the third resistor 33.

When the second switch 42 has the on state, a ratio of the voltage of the second resistor 32 to the voltage between the third node M3 and the fifth node M5 is equal to a ratio of the resistance of the second resistor 32 to the sum of the resistances of the second resistor 32 and the fourth resistor 34.

The first switching mode is to the first capacitor C₁The mode of charging the voltage across the first resistor 31. When the control unit 260 performs the first switching modeAt this time, the control unit 260 controls the first switch 41 to be turned on, controls the second switch 42 to be turned off, controls the first switch circuit 210 to be turned on, controls the second switch circuit 220 to be turned off, and controls the third switch circuit 230 to be turned off. When the control unit 260 performs the first switching mode, the control unit 260 may control the fourth switching circuit 240 to be in an on or off state.

The second switching mode is to detect the first capacitor C₁The pattern of voltages across. When the control unit 260 executes the second switching mode, the control unit 260 controls the first switching circuit 210 to be in an off state and controls the third switching circuit 230 to be in an on state. When the control unit 260 performs the second switching mode, the control unit 260 may control each of the first switch 41, the second switch 42, the second switching circuit 220, and the fourth switching circuit 240 to be in an on or off state.

The third switching mode is to charge the second capacitor C with the voltage across the second resistor 32₂The mode (2). When the control unit 260 executes the third switching mode, the control unit 260 controls the first switch 41 to be in the off state, controls the second switch 42 to be in the on state, controls the first switching circuit 210 to be in the off state, controls the second switching circuit 220 to be in the on state, and controls the fourth switching circuit 240 to be in the off state. When the control unit 260 performs the third switching mode, the control unit 260 may control the third switching circuit 230 to be in an on or off state.

The fourth switching mode is to detect the second capacitor C₂The pattern of voltages across. When the control unit 260 performs the fourth switching mode, the control unit 260 controls the second switching circuit 220 to be in an off state and controls the fourth switching circuit 240 to be in an on state. When the control unit 260 performs the fourth switching mode, the control unit 260 may control each of the first switch 41, the second switch 42, the first switching circuit 210, and the third switching circuit 230 to be in an on or off state.

The control unit 260 may perform the first switching mode during a first period and then perform the second switching mode during a second period. Control unit260 may determine the first voltage based on a first digital signal generated by the ADC 250 at a first point in time within the second period. The first voltage is indicative of the voltage V across the first resistor 31 at a first point in time₁。

The control unit 260 may perform the third switching mode during the third period and then perform the fourth switching mode during the fourth period. The control unit 260 may determine the second voltage based on the second digital signal generated by the ADC 250 at the second time point within the fourth period. The second voltage is indicative of the voltage V across the second resistor 32 at a second point in time₂。

These four switching modes may be performed in the order of the first switching mode, the second switching mode, the third switching mode, and the fourth switching mode. In this case, the second and third periods may be equal, or may at least partially overlap. Upon detection of the first capacitor C₁At a voltage across it, can be applied to the second capacitor C₂Charging the voltage across the second resistor 32.

Alternatively, the four switching modes may be performed in the order of the third switching mode, the fourth switching mode, the first switching mode, and the second switching mode. In this case, the fourth period and the first period may be equal, or may at least partially overlap. Upon detection of the second capacitor C₂At the voltage of both ends, can be applied to the first capacitor C₁The voltage across the first resistor 31 is charged.

Before or after determining the first and second voltages, the control unit 260 may determine the voltage V of the battery 10 by performing the fifth switching mode during the fifth period and then performing the second switching mode during the sixth period_Batt. When the control unit 260 executes the fifth switching mode, the control unit 260 controls the first switch 41 to be in an on state, controls the second switch 42 to be in an on state, controls the first switching circuit 210 to be in an on state, controls the second switching circuit 230 to be in an off state, controls the third switching circuit 230 to be in an off state, and controls the fourth switching circuit 240 to be in an off state. The control unit 260 may be controlled by the ADC based on the third time point within the sixth period250 to determine the voltage V of the battery 10_Batt。

Alternatively, the control unit 260 may measure the voltage of each of the plurality of battery cells B1-Bn and the voltage of the battery 10 using a voltage detection circuit (not shown, included in the electrical leakage detection apparatus 200) electrically connected to each of the plurality of battery cells B1-Bn, before or after determining the first voltage and the second voltage.

The duration of each of the first period, the second period, the third period, the fourth period, the fifth period, and the sixth period may be preset. In addition, a time difference between a start time of the earliest period and an end time of the latest period among the first period, the second period, the third period, the fourth period, the fifth period, and the sixth period may be equal to or less than a preset diagnosis execution time.

As shown in fig. 2, assume that battery cell B_iAnd battery core B_i+1At the point of connection P between_LeakElectrically short-circuited to the chassis 2.

The voltage of the first resistor 31 is equal to the first capacitor C when the first switching mode is being performed at the control unit 260₁At a voltage of (2), from the connection point P_LeakInsulation resistance R_LeakA chassis 2, a first resistor 31, a first switch 41, a third resistor 33, a negative terminal P₁And battery cell B₁-B_iForming a closed loop circuit. Thus, the connection point P_LeakAnd a negative terminal P₁Voltage V between_AInsulation resistance R_LeakAnd a first voltage V₁Having the relationship of formula 1 above.

The voltage of the second resistor 32 is equal to the second capacitor C when the third switching mode is being performed by the control unit 260₂At a voltage of from the positive terminal P₂A fourth resistor 34, a second switch 42, a second resistor 32, a chassis 2, an insulation resistor R_LeakConnection point P_LeakAnd battery cell B_i+1-B_nForming a closed loop circuit. Therefore, when the resistance of each of the first resistor 31 and the second resistor 32 is R₁And the resistance of each of the third resistor 33 and the fourth resistor 34 is R₃While, the positive terminal P₂And a connection point P_leakVoltage V between_BInsulation resistance R_LeakAnd a second voltage V₂Having the relationship of formula 2 above. Therefore, the above equations 3 to 5 are also commonly applied to the electric leakage detecting device 200 according to the second embodiment.

When the insulation resistance R_LeakWhen the voltage is less than the predetermined threshold value, the control unit 260 may determine that the electric leakage occurs between the battery 10 and the chassis, and generate an electric leakage alarm signal.

Hereinafter, a leakage detection method that can be performed by the leakage detection apparatus 100 according to the first embodiment and a leakage detection method that can be performed by the leakage detection apparatus 200 according to the second embodiment will be described. Each of the electric leakage detection methods described below will be started in response to the occurrence of a predetermined event, for example, key-off of the electric vehicle 1.

Fig. 3 is a flowchart exemplarily illustrating an electrical leakage detection method that can be performed by the electrical leakage detection apparatus according to the first embodiment as illustrated in fig. 1.

Referring to fig. 1 and 3, in step S310, the control unit 160 performs a first switching mode during a first period. Therefore, the capacitor C is charged to the voltage of the first resistor 11 during the first period.

In step S320, the control unit 160 performs the second switching mode during the second period. Accordingly, during the second period, the capacitor C is electrically separated from the first and second switch circuits 110 and 120, but electrically connected between the first and eighth nodes N1 and N8.

In step S330, the control unit 160 determines the first voltage V based on the digital signal generated by the ADC150 at the first time point within the second period₁。

In step S340, the control unit 160 performs the third switching mode during the third period. Therefore, during the third period, the capacitor C is charged to the voltage of the second resistor 12.

In step S350, the control unit 160 performs the second switching mode during the fourth period. Accordingly, during the second period, the capacitor C is electrically separated from the first and second switch circuits 110 and 120, but electrically connected between the first and eighth nodes N1 and N8.

In step S360, the control unit 160 determines the second voltage V based on the digital signal generated by the ADC150 at the second time point within the fourth period₂。

In step S370, the control unit 160 bases on the first voltage V₁And a second voltage V₂(see equation 3) to determine the insulation resistance R indicating the insulation state (insulation damage) between the battery 10 and the chassis 2_Leak。

In step S380, the control unit 160 determines the insulation resistance R_LeakWhether less than a threshold. When the value of step S380 is yes, step S385 may be performed.

In step S385, the control unit 160 determines the leakage position of the battery 10 with respect to the chassis 2. That is, in step S385, the control unit 160 determines the first diagnostic voltage V_AOr a second diagnostic voltage V_BAnd (c) to determine whether the battery 10 is electrically disconnected from the chassis 2 (see equations 4 and 5). Step S385 may be omitted from the method of fig. 3. That is, when the value of step S380 is yes, step S390 may be performed.

In step S390, the control unit 160 generates a leakage alarm signal. The leakage warning signal includes information indicating a location of the leakage.

Fig. 4 is a flowchart exemplarily illustrating an electrical leakage detection method that can be performed by the electrical leakage detection apparatus according to the second embodiment as illustrated in fig. 2.

Referring to fig. 2 and 4, in step S410, the control unit 260 performs a first switching mode during a first period. Thus, during the first period of time, the first capacitor C₁The voltage charged in the first resistor 31.

In step S420, the control unit 260 performs the second switching mode during the second period. Therefore, during the second period, the first capacitor C₁Is electrically separated from the first switching circuit 210, but is electrically connected between the first node M1 and the tenth node M10.

In step S430, the control unit260 determine the first voltage V based on the first digital signal generated by the ADC 250 at the first point in time within the second period₁。

In step S440, the control unit 260 performs the third switching mode during the third period. Therefore, during the third period, the second capacitor C₂The voltage charged in the second resistor 32. Step S440 may be performed simultaneously with step S420 or S430.

In step S450, the control unit 260 performs a fourth switching mode during a fourth period. Therefore, during the fourth period of time, the second capacitor C₂Is electrically separated from the second switching circuit 220, but is electrically connected between the first node M1 and the eleventh node M11.

In step S460, the control unit 260 determines the second voltage V based on the second digital signal generated by the ADC 250 at the second time point within the fourth period₂。

In step S470, the control unit 260 bases on the first voltage V₁And a second voltage V₂To determine an insulation resistance R indicating an insulation state (insulation breakdown) between the battery 10 and the chassis 2_Leak(see formula 3).

In step S480, the control unit 260 determines the insulation resistance R_LeakWhether less than a threshold. When the value of step S480 is yes, step S485 may be performed.

In step S485, the control unit 260 determines the leakage position of the battery 10 with respect to the chassis 2. That is, in step S485, the control unit 260 determines the first diagnostic voltage V_AOr a second diagnostic voltage V_BAnd determines a position within the battery 10 that is electrically disconnected from the chassis 2 (see equations 4 and 5). Step S485 may be omitted from the method of fig. 4. That is, when the value of step S480 is yes, step S490 may be performed.

In step S490, the control unit 260 generates a leakage alarm signal.

Although fig. 3 and 4 show the determination of the first voltage V₁In determining the second voltage V₂Before the step of (1), but determining the second voltage V₂May be in determining the first electricityPressure V₁Before the step (2). The embodiments of the present disclosure described above are not realized only by the apparatuses and methods, and may be realized by programs that realize functions corresponding to the configurations of the embodiments of the present disclosure or recording media on which the programs are recorded, and such realization can be easily realized by those skilled in the art in light of the disclosure of the aforementioned embodiments.

The embodiments of the present disclosure described above are not realized only by the apparatuses and methods, and may be realized by programs that realize functions corresponding to the configurations of the embodiments of the present disclosure or recording media on which the programs are recorded, and such realization can be easily realized by those skilled in the art in light of the disclosure of the aforementioned embodiments.

Although the present disclosure has been described above with respect to a limited number of embodiments and drawings, the present disclosure is not limited thereto, and it will be apparent to those skilled in the art that various modifications and changes may be made without departing from the technical aspects of the present disclosure and the equivalent scope of the appended claims.

In addition, since many substitutions, modifications and changes may be made to the present disclosure by those skilled in the art without departing from the technical aspects of the present disclosure, the present disclosure is not limited by the above embodiments and the drawings, and part or all of the embodiments may be selectively combined to make various modifications to the present disclosure.