阅读说明：本技术 用于识别pen导体上的电压的di断路器装置和操作方法 (DI circuit breaker apparatus and method of operation for identifying voltage on PEN conductor ) 是由 尼古拉斯·舒克 于 2018-03-06 设计创作，主要内容包括：本发明涉及一种DI断路器装置,DI断路器装置具有用于检测相位导体和中性导体中的故障电流的求和电流转换器且具有用于识别保护接地导体的故障状态的识别器件。识别器件在输入侧上连接到相位导体、中性导体和保护接地导体,且在输出侧上连接到用于控制DI断路器的开关级。DI断路器适用于切换相位导体、中性导体和保护接地导体中的开关触头。识别器件将保护接地导体上的相位电压的存在检测为故障状态。识别器件具有电容传感器,当用户触摸时,电容传感器形成具有相对于地电势的阻抗的电容器。识别器件还具有评估电子器件,评估电子器件适用于通过将传感器连接到相位导体且与其分开地连接到中性导体来确定相位位置。当评估电子器件确定在相位导体处存在相位的情况下在中性导体与保护接地导体之间不存在电压时,评估电子器件得出关于保护接地导体上不存在相位电压的结论。另外,描述了一种对应的操作方法。(The invention relates to a DI circuit breaker arrangement with a summing current converter for detecting fault currents in the phase and neutral conductors and with identification means for identifying a fault state of the protective earth conductor. The identification device is connected on the input side to the phase conductor, the neutral conductor and the protective earth conductor and on the output side to a switching stage for controlling the DI circuit breaker. DI circuit breakers are suitable for switching the switching contacts in the phase, neutral and protection earth conductors. The identification device detects the presence of a phase voltage on the protective earth conductor as a fault condition. The identification device has a capacitive sensor which, when touched by a user, forms a capacitor having an impedance relative to ground potential. The identification device also has evaluation electronics which are adapted to determine the phase position by connecting the sensor to the phase conductor and separately therefrom to the neutral conductor. When the evaluation electronics determines that there is no voltage between the neutral conductor and the protective ground conductor with the phase present at the phase conductor, the evaluation electronics draw conclusions about the absence of a phase voltage on the protective ground conductor. In addition, a corresponding method of operation is described.)

1. DI circuit breaker arrangement with a summing current converter (22) for detecting fault currents in the phase conductor (1) and the neutral conductor (2) and with identification means (14) for identifying a fault state of the protective earth conductor (3),

wherein the identification means (14) are connected on the input side to the phase conductor (1), the neutral conductor (2) and the protective earth conductor (3) and on the output side to a switching stage (19) for controlling a DI circuit breaker (21), wherein the DI circuit breaker (21) is adapted to switch switching contacts (25, 26, 27) in the phase conductor (1), the neutral conductor (2) and the protective earth conductor (3), wherein the identification means (14) identify the presence of a phase voltage on the protective earth conductor (3) as a fault state,

wherein the content of the first and second substances,

the identification device (14) has a capacitive sensor (17), the capacitive sensor (17) forming a capacitor having a capacitive reactance with respect to a ground potential when touched by a user, wherein the identification device (14) further has evaluation electronics (14a), the evaluation electronics (14a) being adapted to determine a phase position by connecting the sensor (17) to the phase conductor (1) and separately therefrom to the neutral conductor (2), wherein the evaluation electronics (14a) draw a conclusion as to the absence of a phase voltage on the protective ground conductor (3) when the evaluation electronics (14a) determines that no voltage is present between the neutral conductor (2) and the protective ground conductor (3).

2. The DI circuit breaker apparatus of claim 1,

an outer side (28) of a dielectric housing (29) of the DI circuit breaker arrangement forms the capacitor with an electrical conductor (30) of the housing when touched by a user.

3. The DI circuit breaker apparatus of claim 2 wherein,

the electrical conductor (30) is accommodated in a housing gap, attached to the outer side (28) of the housing or is or has a coating on the inner side (31) of the housing (29).

4. The DI circuit breaker apparatus of claim 2 or 3, wherein,

the outer side (28) of the housing (29) is ergonomically shaped to create a large area of contact between a user's hand or a glove surrounding the hand when the user grips the housing (29) with the hand or glove.

5. The DI circuit breaker apparatus of any one of claims 2 to 4,

the capacitor is supplied with a voltage via the electrical conductor (30).

6. A DI circuit breaker arrangement according to any preceding claim,

the capacitance of the capacitor is determined according to C ═ ea/d (equation 1), where e is the dielectric coefficient of the dielectric, which is the sum of the shell thickness, the human skin thickness, the air that may be trapped, and optionally the glove material thickness, and a is the surface area of the electrical conductor (30) at the inner side (31) covered by the user touch.

7. A DI circuit breaker arrangement according to any preceding claim,

the evaluation electronics (14a) are adapted to determine the phase position on the phase conductor (1) and the neutral conductor (2) by connecting the phase conductor (1) and the neutral conductor (2) to the sensor (17) separately from one another and testing for the presence of a voltage drop in each case.

8. The DI circuit breaker apparatus of claim 7,

the evaluation electronics (14a) are adapted to determine the phase position via qualitatively detected voltage drops at the phase conductor (1) and the neutral conductor (2) corresponding to the following truth table:

9. a DI circuit breaker arrangement according to any preceding claim,

the microcontroller is also suitable for testing the phase conductor (1) for the protective earth conductor (3) and the neutral conductor (2) for the protective earth conductor (3) with knowledge of the phase position to obtain a voltage drop, wherein the evaluation electronics (14a) draw a conclusion that the protective earth conductor (3) is functioning properly only if there is a voltage drop corresponding to the phase position determined with respect to the phase conductor (1) and no voltage drop corresponding to the phase position determined with respect to the neutral conductor (2) or if the voltage drop is below a touch voltage, preferably below 50V.

10. The DI circuit breaker apparatus of claim 9,

the evaluation electronics (14a) are adapted to determine the state of the protective earth conductor (3) by testing the phase conductor (1) for the protective earth conductor (3) and the neutral conductor (2) for the protective earth conductor (3) to obtain voltage drops corresponding to the following truth table:

11. a method for operating a DI circuit breaker arrangement according to any preceding claim, the method comprising the steps of:

-touching the sensor (17) of the DI circuit breaker device with a hand, optionally enclosed in a glove, wherein a capacitor is formed with a capacitive reactance with respect to ground potential;

-connecting the phase conductor (1) and the neutral conductor (2) separately from each other to the sensor (17) and determining therefrom a phase position;

-testing the phase conductor (1) for the protection earth conductor (3) and the neutral conductor (2) for the protection earth conductor (3) to obtain a voltage drop, knowing the phase position;

-closing the switch contacts of the phase conductor (1), neutral conductor (2) and protective earth conductor (3) only if the test shows that the protective earth conductor is present/has a low impedance and/or no voltage.

12. The method of claim 11, wherein

The method further comprises the following steps: gripping the housing (29) of the DI circuit breaker device such that the largest possible contact area is created between the user's hand or glove and the outside (28) of the housing (29).

Background

The invention starts from a DI circuit breaker arrangement having the features of the preamble of claim 1. Such a circuit breaker arrangement is known from EP 0806825B 1.

In the DI circuit breaker arrangements known from the prior art, the identification means have a sensor which can be touched by a user and a sensor surface comprising an electrically conductive material which, when touched by a user, is pulled to ground potential, provided that the necessary electrical contact is made between the hand of the user and the sensor surface by the touch. The identification device is electrically connected to the protective earth conductor so that when touched, a conclusion can be drawn as to whether the protective earth conductor is voltage-free by detecting a voltage drop between the conductive sensor surface and the protective earth conductor.

However, the known DI circuit breaker arrangement has the following disadvantages: they also enable electrical isolation to be switched on, for example, because the user wears non-conductive or poorly conductive gloves, rendering the safety function ineffective. In addition, a protective earth conductor with an insufficiently low impedance can also be detected as "good" in this way. Therefore, the existing sensors are not sufficient to achieve a reliable identification of the condition of the protective earth conductor, in particular to ensure that no voltage is present therein, in particular when using protective clothing (gloves, shoes, etc.).

It is therefore an object of the present invention to further improve the above-mentioned DI circuit breaker arrangement in such a way that it also allows a reliable inspection protection of the grounding conductor when the DI circuit breaker arrangement is actuated in an electrically isolated manner.

Disclosure of Invention

This object is achieved by a DI circuit breaker arrangement having the features of claim 1. Independent claim 12 relates to a corresponding method of operation. The dependent claims relate to advantageous embodiment forms of the invention.

The identification device is thus provided with a capacitive sensor which, when touched by a user, forms a capacitor with a capacitive reactance with respect to ground potential, and with evaluation electronics, for example a microcontroller, which are adapted to determine the position of the phase conductor by connecting the sensor to the phase conductor and separately therefrom to the neutral conductor, and to draw a conclusion as to the absence of a phase voltage on the protective ground conductor when the evaluation electronics determines that no voltage is present between the neutral conductor and the protective ground conductor in the event that a phase is present at the phase conductor.

Thus, the capacitive sensor surface is utilized instead of the conductive sensor surface used in the prior art circuit breaker devices, so that no direct conductive connection to the sensor surface needs to be made. In order to generate an evaluable signal, the sensor should advantageously be configured such that a sufficiently large sensor signal is provided even in the case of thick protective clothing. The starting point of the sensor principle is the plate capacitance, which can be calculated as follows:

it is desirable to obtain a high sensor capacitance so that as high a current as possible is regulated via the resulting capacitive reactance:

however, this sensor current may not be an order of magnitude that can harm the user. In particular, a current intensity of a few microamps should be targeted.

Thus, it may be provided that the outside of the dielectric housing of the DI circuit breaker arrangement forms a capacitor with electrical conductors when touched by a user. For example, the electrical conductor may be accommodated in the housing gap, attached to the outside of the housing or may be a coating on the inside of the housing or may have a coating on the inside.

In order to achieve as large a contact surface as possible between the user's hand and the housing and thus a maximum effective capacitor surface a, the outer side of the housing may be shaped in an ergonomic manner so as to create a large area of contact between the user's hand or a glove surrounding the hand when the user grips the housing with the hand or glove. The capacitor may be supplied with a voltage via the electrical conductor. In particular, for this purpose, the electrical conductor can be electrically connected to the identification device.

When determining the capacitance of the capacitor according to equation 1, ε may be the dielectric coefficient of the dielectric and d is the thickness of the dielectric, which may be the sum of the shell thickness, the human skin thickness, the air that may be trapped, and optionally the glove material thickness, where A may be the surface area of the electrical conductor at the inner side covered by the user's touch.

Advantageously, the size of the housing of the DI circuit breaker apparatus, or at least the electrical conductor at the inside of the housing, is increased to at least 3 x 10^-3m²This corresponds approximately to the surface area of both hands. In addition, the housing surface should contact the user's hand as flat as possible, so that the housing has ergonomic several at least at the outer side of the user contactAnd the shape thereof.

The evaluation electronics can be particularly suitable for determining the phase position on the phase conductor and the neutral conductor, since they connect the phase conductor and the neutral conductor in turn to the sensor and test for the presence of a voltage drop in each case. Thus, rather than testing the guard ground conductor directly as provided by known prior art arrangements, the conductors l (n) and n (l) may be initially connected to the capacitive sensor in sequence. From the signal obtained, it is assessed whether a test phase can be introduced, based on the qualitatively detected voltage drop (yes/no). After evaluating the obtained signal, the phase may be associated with a position on the N-conductor or the L-conductor. Thus, the evaluation electronics may be adapted to determine the phase position from the corresponding truth table via qualitatively detected voltage drops at the phase conductor and the neutral conductor:

next, the phase and neutral conductors may be tested against the protection ground conductor. In this way, it can be observed in particular whether the potential difference between the neutral conductor and the protective earth conductor is below the permissible value of the touch voltage, for example below 50V.

Thus, the evaluation electronics may also be adapted to test the phase conductor for the protective earth conductor and the neutral conductor for the protective earth conductor with knowledge of the phase position to obtain a voltage drop, and the evaluation electronics draw the following conclusions: the protective earth conductor operates normally only when there is a voltage drop corresponding to the determined phase position relative to the phase conductor and there is no voltage drop corresponding to the determined phase position relative to the neutral conductor or the voltage drop is below the touch voltage.

The evaluation electronics may be adapted to determine the state of the protective ground conductor by testing the phase conductor against the protective ground conductor and the neutral conductor against the protective ground conductor to obtain a voltage drop corresponding to the following truth table:

if the test of the potential difference between the neutral conductor and the protective earth conductor shows that the potential difference is below the allowed touch voltage, then a test of the quality of the protective earth conductor, in particular a test of a low impedance of the protective earth conductor, can be subsequently performed by the evaluation electronics.

If this quality test is also passed, an enable signal can be sent from the identification device to the switching stage for controlling the DI switch and the output of the DI circuit breaker arrangement can thus be switched on.

According to another aspect, the present invention relates to a method for operating a DI circuit breaker apparatus of the above-described type, the method having the steps of:

-touching a sensor of the DI circuit breaker device with a hand, optionally enclosed in a glove, the capacitor being formed with a capacitive reactance with respect to ground potential;

the phase conductor and the neutral conductor are in turn connected to a sensor and the phase is determined therefrom;

-testing the phase conductor against the guard ground conductor and the neutral conductor against the guard ground conductor to obtain a voltage drop with knowledge of the phase position;

the switch contacts of the phase conductor, the neutral conductor and the protective earth conductor are closed only when the test shows that the protective earth conductor is present/has a low impedance and/or no voltage.

The above method may further comprise: the housing of the DI circuit breaker device is grasped so that the largest possible contact area is created between the user's hand or glove and the outside of the housing. To facilitate this, it may be provided to form the outer side of the housing in an ergonomic manner.

Drawings

Further details of the invention will be described with reference to the accompanying drawings. The figures show:

fig. 1 is a schematic diagram in embodiment form showing a structure of a capacitive sensor for a DI circuit breaker apparatus according to the present invention; and

fig. 2 is a block wiring diagram of a DI circuit breaker apparatus according to a form of embodiment of the present invention.

Detailed Description

Fig. 1 schematically illustrates the structure of a capacitive sensor 17 for a DI circuit breaker arrangement according to a form of embodiment of the present invention. Thus, the sensor 17 is essentially formed by the housing 29 of the DI circuit breaker device. The housing 29 has an electrical conductor 30 at its inner side 31. The electrical conductor 30 may be, for example, a metal coating of the inner side 31 of the housing 29. According to the invention, the electrical conductor 30 can be connected to the evaluation electronics 14a of the identification means 14 in order to be connected to a phase conductor or a neutral conductor for the purpose of determining the phase position (see fig. 2). The housing 29 has a surface 28 that can be enclosed by a user's hand. Said surface constitutes the first electrode of the capacitor formed by the conductor 31. The shell material with thickness d forms the dielectric of the capacitor and has a dielectric coefficient epsilon. The dielectric coefficient describes the dielectric conductivity of the housing material.

The surface area of the electrical conductor 30 at the inner side 31 of the housing 29 is the maximum available sensor surface. The actually realized capacitive surface area a is precisely defined by the overlap of the housing surface 28 enclosed by the user's hand and the sensor surface a. The thickness d of the housing 29 thus precisely forms the distance between the capacitor plates. The effective capacitance as well as the sensor capacitance can be calculated from the above values based on the above equation (equation 1) for the plate capacitor. This may be performed substantially as follows.

In the following example, the sensor capacitance between the sensor surface and the hand is determined in a simplified manner. The indicated surface area corresponds to the effective capacitive surface of the sensor 17. The dielectric coefficient epsilon is ignored as a parameter in order to focus on the sensor geometry. Assuming that the dielectric coefficient of the uppermost skin is the same as the dielectric coefficient of the glove:

·

thickness d of the uppermost skin layer₁＝30·10^-6m；

Thickness d of the glove₂＝7·10^-3m；

The thickness of the housing is about 1 mm;

surface A of the thumb₁Roughly correspond to

(20·10^-3m)·(20·10^-3m)＝400·10^-6m²；

Surface A of the hand₂Roughly correspond to

(150·10^-3m)·(100·10^-3m)＝15·10^-3m²。

Inserting the value d in equation 1₁And A₁The following results: gloved thumb on sensor.

By d₂In place of d₁The following results: gloved thumb on the sensor.

Assume skin capacitance C₁And glove capacitor C₂The series connection of (a) gives the following total capacitance:

calculating the ratio of the results without a glove in equation 3 to the results with a glove in equation 5 yields the following values:

due to the capacitance C and the reactance X_CIndirectly proportional, and therefore a lower sensor capacitance results in a lower sensor current (based on ohm's law). Thus, is higherResulting in a higher sensor current. Using A₂And d₂Performing the same capacitance calculation (equations 5 to 6) yields the result of the following new ratio:

thus, with the sensor surface remaining unchanged, the sensor signal difference is 234.33 times (independent of the material constant) when the glove is used. If the sensor surface increases to the size of the hand surface, the signal is only 7.22 times worse with gloves compared to the thumb sensor known in the art with a corresponding small sensor surface. Thus, the glove may be partially compensated by the sensor surface. In order to be fully compensated, the surface area must be increased to 93.33 × 10 in this case^{- 3}m². However, this parameter is limited by the amount of surface area of the user's hand, since only the overlap of the hand surface and the sensor surface is considered as the effective surface area.

Thus, increasing the effective sensor surface to the size of both hands, for example, to 30x 10^-3m²Is advantageous. Furthermore, the housing surface 28 should contact the user's hand in as flat a manner as possible, so that an ergonomic design of the housing surface 28 is preferred.

Fig. 2 shows a block wiring diagram of a preferred embodiment form of the DI circuit breaker arrangement according to the present invention. In this case, the L-phase conductor 1 is connected to a protective impedance 5 via a line 4, and the neutral conductor 2 is connected to a protective impedance 7 via a line 6. The protective impedances 5, 7 are connected via lines 8, 9 to a node 10 on the output side. The node 10 is connected via a line 11 to a further protective impedance 12 which is connected on the output side via a line 13 to a device 14 for detecting the state of the protective ground conductor. The protective impedances 5, 7 and 12 are used to limit the current. The device 14 is also connected to the protective earth conductor 3 via line 15 and to the sensor 17 via line 16. According to the invention, the sensor 17 is a capacitive sensor, such as the sensor described with reference to fig. 1.

The output of the device 14 is connected via a conductor 18 to a switching stage 19, which switching stage 19 switches a DI ground fault interrupter 21 via a line 20. The DI ground fault interrupter 21 is connected to a summing current converter 22, the primary winding of which summing current converter 22 is formed by a phase conductor 1 and a neutral conductor 2. The summing current converter 22 also has a secondary winding which conducts the induced voltage via lines 23, 24 to evaluation electronics contained in the DI switch 21. The DI switch 21 is mechanically connected to switch contacts 25, 26, 27, which are connected into the lines 1, 2, 3.

Depending on the position of the phase conductor, there is a current flow from line 4 via the protective impedance 5 and line 8 or via line 6, protective impedance 7 and line 9 to node 10 and from node 10 via line 11, protective impedance 12, conductor 13, identification device 14 and line 15 to the protective earth conductor 3. Normally, i.e. when the phase conductor 1, the neutral conductor 2 and the protective earth conductor 3 are correctly connected, this current flows through the device 14 via the line 15 to the protective earth conductor 3.

However, if this current is not present, for example because the protective earth conductor is not connected or interrupted, the device 14 detects this fault condition because no current flows through the conductor 15 to the protective earth conductor 3 and switches the DI breaker 21 via the isolated switching stage 19, said DI breaker 21 opening the switching contacts 25, 26, 27 and interrupting the conductors 1, 2, 3 accordingly.

In addition to this, the device 14 is configured to detect the presence of an external or line voltage protecting the ground conductor 3. A capacitive sensor 17, which forms a capacitor with a capacitive reactance with respect to ground when touched by a user, is used for this purpose. The identification means 14 has evaluation electronics 14a, said evaluation electronics 14a being adapted to determine the position of the phase conductor by connecting the sensor 17 to the phase conductor 1 and connecting the sensor 17 to the neutral conductor 2 separately from the phase conductor 1. Thus, instead of directly testing the guard ground conductor provided in prior art devices, the neutral conductor and the guard ground conductor are first connected to the sensor in sequence in order to correlate the phase with the position on the L or N conductor. Based on the obtained signal, it is assessed whether the next test phase can be started:

after the phase position is determined, the phase and neutral conductors are tested against the protection ground conductor. After signal evaluation, it can be assessed whether there is a potential difference between the neutral conductor and the protective earth conductor, and if so, whether this potential difference is below the touch voltage. For example, if the potential difference is less than 50V, then the touch voltage can be assumed to be negligible. The signal evaluation for assessing the potential difference between the neutral conductor and the PE may be performed corresponding to the following truth table:

a test of the quality of the protection earth conductor may then be performed, for example by determining the resistance of the protection earth conductor.

The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be of importance for the implementation of the invention both individually and in any combination.