阅读说明：本技术 充电装置 (Charging device ) 是由 青木智哉 南井俊彦 于 2020-01-14 设计创作，主要内容包括：本发明提供一种充电装置,当对接入口连接了连接器时,车辆的ECU计测导频信号的占空因数。然后,ECU基于计测到的占空因数来计算第一上限电流。另外,当对接入口连接了连接器时,ECU根据电压传感器的检测值来判定从供电设备施加于接入口的电压。ECU基于上述判定出的电压而从存储器将第二上限电流读出并设定。ECU将第一上限电流与第二上限电流进行比较,在第一上限电流比第二上限电流小的情况下对限制电流设定第一上限电流的值。另一方面,ECU在第一上限电流为第二上限电流以上的情况下对限制电流设定第二上限电流的值。(The invention provides a charging device, when a connector is connected to a docking port, an ECU of a vehicle measures a duty factor of a pilot signal. Then, the ECU calculates a first upper limit current based on the measured duty cycle. When the connector is connected to the inlet, the ECU determines a voltage applied from the power supply device to the inlet based on a detection value of the voltage sensor. The ECU reads and sets the second upper limit current from the memory based on the determined voltage. The ECU compares the first upper limit current with the second upper limit current, and sets the value of the first upper limit current for the limiting current when the first upper limit current is smaller than the second upper limit current. On the other hand, the ECU sets the value of the second upper limit current for the limit current when the first upper limit current is equal to or greater than the second upper limit current.)

1. A charging device for charging a power storage device mounted on a vehicle with electric power supplied from a power supply facility outside the vehicle via a charging cable, the charging device comprising:

a charging port configured to be connectable to a connector provided in the charging cable;

a voltage sensor that detects a voltage applied from the power supply apparatus to the charging port; and

a control device that sets an upper limit of a charging current to be supplied to the power storage device,

the control means calculates a first upper limit current from a pilot signal received via the charging cable,

the control device sets a second upper limit current according to a detection value of the voltage sensor,

the control device sets the upper limit of the charging current based on the smaller one of the first upper limit current and the second upper limit current.

2. The charging device according to claim 1, wherein the charging device,

the control device stores in advance a relationship between a voltage of the power supply device and a rated current of the charging cable,

the control device sets the second upper limit current using the detected value of the voltage sensor and the relationship.

Technical Field

The present disclosure relates to a charging device that charges a power storage device mounted on a vehicle using electric power supplied from a power supply outside the vehicle via a charging cable.

Background

Japanese patent application laid-open No. 2017-158225 discloses a charging system that charges a power storage device mounted on a vehicle with electric power supplied from a power supply apparatus outside the vehicle via a charging cable. The power supply apparatus transmits a pilot signal oscillating at a duty cycle corresponding to a permissible value of an alternating current (hereinafter also referred to as "upper limit current") that can be supplied to the vehicle, to the vehicle. The vehicle calculates the upper limit current from a pilot signal received from the power supply apparatus via the charging cable. In addition, the vehicle calculates a charging current command value indicating a current to be drawn from the power supply apparatus, based on the SOC of the power storage device and the like. The vehicle controls charging of the power storage device based on the smaller one of the upper limit current and the charging current command value.

Disclosure of Invention

The upper limit current is sometimes determined, for example, according to the rated current of the charging cable. In order to prevent damage to the charging cable due to excessive current flow, it is important to correctly read the pilot signal and perform current control so that the current flowing through the charging cable does not exceed the upper limit current (rated current).

However, (1) an oscillation device or the like for generating a pilot signal included in the power supply equipment or the charging cable may fail. Further, (2) the vehicle may be affected by noise or the like, and the pilot signal may be erroneously measured. In the case of (1) or (2), a value larger than the original upper limit current (rated current) may be calculated as the upper limit current. Hereinafter, the case of (1) or (2) is also referred to as "misalignment of pilot signals".

In the charging system for a vehicle disclosed in japanese patent application laid-open No. 2017-158225, when, for example, a case is assumed in which the original upper limit current is smaller than the charging current command value (original upper limit current < charging current command value), if the upper limit current calculated due to the occurrence of the offset of the pilot signal is larger than the charging current command value, the current control is performed based on the charging current command value smaller than the calculated upper limit current. In this case, an excessive current exceeding the original upper limit current may flow through the charging cable, and the charging cable may be damaged.

The present disclosure has been made to solve the above-described problem, and an object thereof is to suppress an excessive current from flowing to a charging cable even when offset of a pilot signal occurs.

The disclosed charging device for a vehicle charges a power storage device mounted on the vehicle using power supplied from a power supply device external to the vehicle via a charging cable, and is provided with: a charging port configured to be connectable to a connector provided in a charging cable; a voltage sensor that detects a voltage applied from the power supply apparatus to the charging port; and a control device that sets an upper limit of a charging current to be supplied to the power storage device. The control device calculates a first upper limit current from a pilot signal received via the charging cable. The control device calculates a second upper limit current based on the detection value of the voltage sensor. The control device sets the upper limit of the charging current based on the smaller one of the first upper limit current and the second upper limit current.

Among the power supply apparatuses, for example, there are a power supply apparatus of a specification that supplies power having a voltage of 100V to a vehicle and a power supply apparatus of a specification that supplies power having a voltage of 200V to a vehicle. In general, a charging cable corresponding to the specification of the power supply device is used as the charging cable.

According to the above configuration, the upper limit of the charging current is set based on the smaller one of the first upper limit current calculated from the pilot signal and the second upper limit current calculated from the detection value of the voltage sensor. As for the second upper limit current, a voltage applied from the power supply apparatus is detected, and a current corresponding to the detected voltage (e.g., 100V, 200V) is set as the second upper limit current. That is, as the second upper limit current, a current corresponding to the specification of the power supply apparatus is set. The current corresponding to the detected voltage can be predetermined for each voltage, for example. Thus, even if a value larger than the original upper limit current (rated current) to be calculated from the pilot signal is set as the first upper limit current due to the offset of the pilot signal, the upper limit of the charging current is set based on the second upper limit current. Therefore, an excessive current exceeding the rated current can be suppressed from flowing to the charging cable. That is, even when the offset of the pilot signal occurs, it is possible to suppress an excessive current exceeding the rated current from flowing to the charging cable, and to suppress damage to the charging cable.

In one embodiment, the relationship between the voltage of the power supply device and the rated current of the charging cable is stored in the control device in advance. The control device sets the second upper limit current using the detection value of the voltage sensor and the relationship.

According to the above configuration, by detecting the voltage applied from the power feeding device to the charging port and comparing the above relationship, the second upper limit current corresponding to the specification of the power feeding device (i.e., the rated current of the charging cable) can be appropriately set. Further, by appropriately setting the second upper limit current, even if the offset of the pilot signal occurs, the upper limit of the charging current is set based on the appropriately set second upper limit current. Therefore, even when the offset of the pilot signal occurs, it is possible to suppress an excessive current exceeding the rated current from flowing to the charging cable, and to suppress damage to the charging cable.

The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description, which is to be read in connection with the accompanying drawings.

Drawings

Fig. 1 is a diagram showing an example of the overall configuration of a charging system including a charging device according to an embodiment.

Fig. 2 is a diagram showing an example of the circuit configuration of the ECU, the charger, and the power supply device of the vehicle.

Fig. 3 is a time chart showing changes in the pilot signal and the connector connection signal.

Fig. 4 is a flowchart showing the procedure of the process for setting the limiting current executed by the ECU.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and description thereof will not be repeated.

< structures of vehicle and power supply apparatus >

Fig. 1 is a diagram showing an example of the overall configuration of a charging system including a charging device according to the present embodiment. The charging system includes vehicle 1 and power supply apparatus 300. The power supply apparatus 300 is an apparatus for supplying ac power to the vehicle 1. Although an example in which vehicle 1 of the present embodiment is an electric vehicle is described, vehicle 1 is not limited to an electric vehicle as long as it can externally charge a vehicle-mounted power storage device by receiving ac power supplied from power feeding apparatus 300. For example, the vehicle 1 may be a plug-in hybrid vehicle or a fuel cell vehicle.

Vehicle 1 includes power storage device 10, current sensor 15, system main relay (hereinafter also referred to as "smr (systemmain relay")) 20, power Control unit (hereinafter also referred to as "pcu (power Control unit")) 30, power output device 40, and drive wheels 50. Vehicle 1 further includes inlet 70, charge relay 60, and charger 200.

Power storage device 10 is a rechargeable dc power supply, and is formed of a secondary battery such as a nickel-hydrogen or lithium-ion battery, for example. In power storage device 10, in addition to the electric power supplied from ac power supply 310 of power feeding equipment 300, the electric power generated by power output device 40 is stored. As power storage device 10, a capacitor having a large capacity may be used.

Current sensor 15 detects a charging current IB input to and output from power storage device 10, and outputs the detection result to ECU 100.

SMR20 is provided between power storage device 10 and power lines P L1 and N L1. SMR20 is a relay for electrically connecting and disconnecting power storage device 10 to and from power lines P L1 and N L1.

PCU30 collectively shows a power conversion device for receiving electric power from power storage device 10 and driving power output device 40. For example, PCU30 includes an inverter for driving a motor included in power output device 40, a converter for boosting electric power output from power storage device 10, and the like.

The power output device 40 collectively shows a device for driving the drive wheels 50. The power output device 40 includes, for example, a motor or the like that drives the drive wheels 50. In the case where the vehicle 1 is a plug-in hybrid vehicle, the power output device 40 further includes, for example, an engine. The power output device 40 generates electric power by the electric motor that drives the drive wheels 50 during braking of the vehicle, and outputs the generated electric power to the PCU 30.

Input lines AC L1, AC L2, and 70 electrically connected to charger 200 are provided to inlet 70, inlet 70 is configured to be connectable to connector 340 of power supply apparatus 300, signal lines L1, L2 are provided between inlet 70 and ECU100, signal line L1 is a signal line for transmitting pilot signal CP L T for exchanging predetermined information between vehicle 1 and power supply apparatus 300, signal line L2 is a signal line for transmitting connector connection signal PISW indicating a connection state of inlet 70 and connector 340, and pilot signal CP L T and connector connection signal PISW will be described later.

Charging relay 60 is a relay for electrically connecting and disconnecting charger 200 to and from power lines P L1 and N L1, and charging relay 60 switches its open/closed state based on a control signal from ECU 100.

Charger 200 is electrically connected to power storage device 10 via charging relay 60. Charger 200 converts the electric power input to inlet 70 into electric power having a charging voltage of power storage device 10 in accordance with an instruction from ECU 100. The electric power converted by charger 200 is supplied to power storage device 10 via charging relay 60, and power storage device 10 is charged.

The ECU100 includes a CPU (Central Processing Unit) 110, a Memory (RAM (Random Access Memory)) 120, a ROM (Read Only Memory)) 120, and an input/output buffer (not shown) for inputting and outputting various signals. The CPU110 expands and executes a program stored in the ROM on the RAM. The processing executed by the CPU110 is recorded in the program stored in the ROM. The ECU100 executes predetermined arithmetic processing by the CPU110 based on various signals input from the input/output buffer and information stored in the memory 120, and controls the respective devices (the SMR20, the PCU30, the charging relay 60, the charger 200, and the like) based on the arithmetic result so that the vehicle 1 is in a desired state. The control is not limited to the processing realized by software, and may be configured and processed by dedicated hardware (electronic circuit).

The power supply apparatus 300 includes an ac power supply 310 outside the Vehicle, an EVSE (Electric Vehicle supply apparatus) 320, and a charging cable 330. At the distal end of charging cable 330, connector 340 configured to be connectable to inlet 70 of vehicle 1 is provided.

The ac power supply 310 is configured by, for example, a commercial system power supply, but is not limited thereto, and various power supplies can be applied.

The EVSE320 controls supply/cutoff of ac power from the ac power supply 310 to the vehicle 1 via the charging cable 330. The EVSE320 is provided in a charging station for supplying electric power to the vehicle 1, for example. The EVSE430 meets, for example, requirements of the SAE J1772(SAE Electric Vehicle Conductive Charge Coupler) standard. The function of the EVSE320 is not limited to being provided in a Charging station, and for example, a CCID (Charging Circuit Interrupt Device) box having the function of the EVSE320 may be provided in a Charging cable. In this case, for example, a receptacle plug provided at one end (the side opposite to the connector 340) of the charging cable is connected to the ac power supply 310.

The EVSE320 includes a CCID321 and a CP L T control circuit 322 the CCID321 is a relay provided in a power supply path from the ac power source 310 to the vehicle 1, and is controlled by the CP L T control circuit 322.

The CP L T control circuit 322 generates a pilot signal CP L T that communicates with the ECU100 of the vehicle 1, and outputs the pilot signal CP L T to the ECU100 through a dedicated signal line included in the charging cable 330, the pilot signal CP L T receives an operation of a potential in the ECU100, the CP L T control circuit 322 controls the CCID321 based on the potential of the pilot signal CP L T, that is, by operating the potential of the pilot signal CP L T in the ECU100, the CCID321 can be remotely operated from the ECU 100.

Fig. 2 is a diagram showing an example of the circuit configuration of ECU100, charger 200, and power feeding apparatus 300 of vehicle 1.

The charger 200 includes a filter circuit 205, a PFC (Power Factor Correction) circuit 210, an inverter 215, and a rectifier circuit 220. Filter circuit 205, PFC circuit 210, inverter 215, and rectifier circuit 220 are connected in this order to the circuit from inlet 70 to power storage device 10.

The filter circuit 205 removes noise included in the ac power input from the inlet 70, and outputs the ac power from which the noise has been removed to the PFC circuit 210.

The PFC circuit 210 converts the ac power supplied from the filter circuit 205 into dc power based on a control signal from the ECU100 and outputs the dc power to the converter 215.

The inverter 215 converts the dc power received from the PFC circuit 210 into ac power based on a control signal from the ECU100 and outputs the ac power to the rectifier circuit 220. The inverter 215 is constituted by a single-phase bridge circuit, for example.

The rectifier circuit 220 converts the ac power output from the inverter 215 into dc power and outputs the dc power. The dc power output from rectifier circuit 220 is supplied to power storage device 10.

Charger 200 also includes a voltage sensor 80. The voltage sensor 80 detects the voltage VIN on the input side of the filter circuit 205. The voltage VIN can be regarded as a voltage applied from the power supply apparatus 300 to the inlet 70.

< Pilot Signal and connector connection Signal >

The EVSE320 of the power supply equipment 300 includes an electromagnetic coil 325 and a control unit 326 in addition to the CCID321 and CP L T control circuit 322, the CP L T control circuit 322 includes an oscillation device 323, a resistor R20, and a voltage sensor 324.

CCID321 (hereinafter also referred to as "CCID relay 321") is provided in a power supply path to vehicle 1 and is controlled by CP L T control circuit 322, and when CCID relay 321 is in an open state, the power supply path is cut off, and when CCID relay 321 is in a closed state, power can be supplied from ac power supply 310 to vehicle 1 (charger 200) via charging cable 330.

The CP L T control circuit 322 outputs the pilot signal CP L T to the ECU100 via the connector 340 and the inlet 70 as described above, the pilot signal CP L T is used as a signal for remotely operating the CCID relay 321 from the ECU100 by operating the potential of the ECU100, the CP L T control circuit 322 controls the CCID relay 321 based on the potential of the pilot signal CP L T, and the pilot signal CP L T is used as a signal for notifying the ECU100 of the rated current of the charging cable 330 from the CP L T control circuit 322.

The control unit 326 includes a CPU, a memory, an input/output buffer, and the like (none of which is shown), inputs and outputs signals from various sensors and the CP L T control circuit 322, and controls the operation of the CP L T control circuit 322.

When connector 340 and inlet 70 are not connected, oscillator 323 outputs pilot signal CP L T that has a potential of V0 and does not oscillate, and when connector 340 is connected to inlet 70 and the potential of pilot signal CP L T becomes V1(V0> V1) lower than V0, oscillator 323 oscillates pilot signal CP L T at a predetermined frequency (e.g., 1kHz) and duty cycle when preparation for power supply to vehicle 1 is completed in EVSE 320.

The duty cycle of the pilot signal CP L T is set according to the rated current of the charging cable 330 the ECU100 of the vehicle 1 is able to detect the rated current of the charging cable 330 based on the duty cycle of the pilot signal CP L T received from the CP L T control circuit 322 via the signal line L1 the relationship between the duty cycle of the pilot signal CP L T and the rated current of the charging cable 330 will be described later.

When the potential of pilot signal CP L T drops to V2 lower than V1 (V1< V2), CP L T control circuit 322 supplies current to electromagnetic coil 325, when current is supplied from CP L T control circuit 322 to electromagnetic coil 325, electromagnetic coil 325 generates electromagnetic force, and CCID relay 321 is closed, whereby a power supply voltage (voltage from ac power supply 310) is applied to inlet 70 via charging cable 330.

The connector 340 includes resistors R6 and R7 and a switch SW 3. Resistors R6, R7, and switch SW3 constitute a circuit for detecting the connection state of connector 340 and inlet 70, together with power supply node 150 provided in ECU100 of vehicle 1, pull-up resistor R4, and resistor R5 provided in inlet 70.

Resistors R6 and R7 are connected in series between signal line L2 and ground line L3, switch SW3 is connected in parallel to resistor R7., switch SW3 is interlocked with button 345 provided in connector 340, switch SW3 is in a closed state when button 345 is not pressed, switch SW3 is in an open state when button 345 is pressed, and resistor R5 is connected between signal line L2 and ground line L3 through inlet 70.

When the connector 340 and the inlet 70 are not connected, a signal having a potential (V3) determined by the voltage of the power supply node 150, the pull-up resistor R4, and the resistor R5 is generated as the connector connection signal PISW on the signal line L2, when the connector 340 and the inlet 70 are connected (the button 345 is not operated), a signal having a potential (V4) determined by the voltage of the power supply node 150, the pull-up resistor R4, the resistors R5, and the resistors R6 is generated as the connector connection signal PISW on the signal line L2, when the button 345 is operated in a state where the connector 340 and the inlet 70 are connected, a signal having a potential (V5) determined by the voltage of the power supply node 150, the pull-up resistor R4, and the resistors R5 to R7 is generated as the connector connection signal PISW on the signal line L2, and therefore, the ECU100 can detect the state of the connection of the connector connection signal PISW 340 and the inlet 70 by detecting the potential of the connector connection signal PISW 340.

The ECU100 includes a resistor circuit 140 and input buffers 131 and 132 in addition to the power supply node 150 and the pull-up resistor R4, the resistor circuit 140 is a circuit for operating the potential of the pilot signal CP L T communicated through the signal line L1 the resistor circuit 140 includes pull-down resistors R2 and R3 and a switch sw2, the pull-down resistor R2 and the switch SW2 are connected in series between the signal line L1 through which the pilot signal CP L T is communicated and the vehicle ground 160, the pull-down resistor R3 is connected between the signal line L1 and the vehicle ground 160, and the switch SW2 is turned on/off according to the signal S2 from the CPU 110.

In a state where the resistor circuit 140 is electrically connected to the CP L T control circuit 322 through the signal line L1, the inlet 70, and the connector 340, when the switch SW2 is turned off (turned off), the potential of the pilot signal CP L T becomes a potential (V1) determined by the pull-down resistor R3, and when the switch SW2 is turned on (turned on), the potential of the pilot signal CP L T becomes a potential (V2) determined by the pull-down resistors R2 and R3.

The input buffer 131 is a circuit for taking in the pilot signal CP L T from the signal line L1 to the CPU110, and the input buffer 132 is a circuit for taking in the connector connection signal PISW from the signal line L2 to the CPU 110.

The CPU110 receives the pilot signal CP L T from the input buffer 131, receives the connector connection signal PISW from the input buffer 132. the CPU110 detects the potential of the connector connection signal PISW, and detects the connection state of the connector 340 and the inlet 70 based on the potential of the connector connection signal PISW.

When connector 340 and inlet 70 are connected, CPU110 requests power supply to power supply apparatus 300 and stops the power supply by operating the potential of pilot signal CP L T with control signal S2 (switch SW 2). specifically, CPU110 requests power supply to power supply apparatus 300 by turning signal S2 on and changing the potential of pilot signal CP L T from V1 to V2. CPU110 requests power supply to power supply apparatus 300 by turning signal S2 off and changing the potential of pilot signal CP L T from V2 to V1.

When CCID relay 321 is in the closed state in EVSE320 by signal S2 being turned on, the power supply voltage is supplied from power supply apparatus 300 to charger 200 via inlet 70. After the predetermined charge preparation process is completed, CPU110 outputs a control signal to charger 200. Thereby, charger 200 operates to perform external charging by ac power supply 310.

Fig. 3 is a time chart showing changes in the pilot signal CP L T and the connector connection signal PISW, the abscissa of fig. 3 indicates time, the potential of the pilot signal CP L T is a potential detected on the power supply apparatus 300 side, specifically, a detection value of the voltage sensor 324 of the CP L T control circuit 322, with respect to the connector connection signal PISW, as described above, the potential V3 indicates that the inlet 70 and the connector 340 are not connected, and the potential V4 indicates that the inlet 70 and the connector 340 are connected.

It is assumed that connector 340 is connected to inlet 70 at time T1 until time T1, since connector 340 and inlet 70 are not connected, the potential of pilot signal CP L T is V0.

When the connector 340 is connected to the inlet 70 at time T1, the potential of the pilot signal CP L T drops to v1, whereby the connection of the connector 340 to the inlet 70 is recognized in the EVSE320, and when the preparation for power supply to the vehicle 1 is completed at time T2, the pilot signal CP L T oscillates.

After that, when the predetermined preparatory process for executing the external charging in vehicle 1 is completed, CPU110 switches signal S2 from off to on at time T3, whereby switch SW2 of resistance circuit 140 is turned on, the potential of pilot signal CP L T becomes v2, and accordingly, CCID relay 321 is in a closed state in power feeding equipment 300, and the power feeding voltage is output from power feeding equipment 300.

In the external charging, the ECU100 detects the rated current of the charging cable 330 based on the Duty factor Duty of the pilot signal CP L T, sets the detected rated current to the first upper limit current Ilim1, and then the ECU100 controls the charging of the power storage device 10 so that the current flowing in the charging cable 330 does not exceed the first upper limit current Ilim1, that is, the ECU100 calculates the upper limit of the charging current IB supplied to the power storage device 10 in accordance with the first upper limit current Ilim1, and controls the charging in the range where the current supplied to the power storage device 10 does not exceed the upper limit of the charging current IB.

The first upper limit current Ilim1 is set, for example, in accordance with SAE J1772 standard (set according to a calculation formula prescribed by SAE J1772 standard). The following expressions (1) to (3) exemplify calculation expressions applied when the Duty factor Duty is 10% to 96%. A1, A2 and A3 in the formula (1) (2) are constants. The case where the Duty factor Duty is less than 10% and the case where it is greater than 96% are also set in conformity with the SAE J1772 standard. The first upper limit current Ilim1 is not limited to be set in compliance with SAE J1772 standard, and may be set in compliance with other standards (for example, GB/T18487 standard).

Ilim1＝Duty×A1(10％≤Duty≤20％)…(1)

Ilim1＝Duty×A1(20％<Duty≤85％)…(2)

Ilim1＝(Duty-A2)×A3(85％<Duty≤96％)…(3)

< second Upper Current >

Here, if the current flowing through the charging cable 330 exceeds the rated current (the first upper limit current Ilim1) of the charging cable 330, there is a possibility that the charging cable 330 is broken, and it is important to correctly read the pilot signal CP L T and appropriately set the first upper limit current Ilim 1.

However, (1) there is a case where a failure occurs in the oscillation device 323 and the like included in the EVSE320, (2) there is a case where an erroneous measurement of the pilot signal CP L T occurs in the ECU100 due to the influence of noise and the like, and in the case (in the case where a mismatch of the pilot signal occurs) such as (1) and (2) described above, there is a possibility that the rated current of the charging cable 330 detected based on the Duty factor Duty of the pilot signal CP L T becomes a value larger than the original rated current of the charging cable 330, that is, there is a possibility that the first upper limit current Ilim1 is set to a value larger than the original rated current of the charging cable 330 when a mismatch of the pilot signal occurs, and if the charging of the power storage device 10 is controlled based on the first upper limit current Ilim1 set in this way, an excessive current exceeding the original rated current of the charging cable 330 may flow in the charging cable 330, and damage of the charging cable 330 may occur.

In the present embodiment, ECU100 sets a limit current Ilim, which is an upper limit of the current supplied from power supply apparatus 300, and determines the upper limit of charging current IB supplied to power storage device 10 based on limit current Ilim. Then, ECU100 controls charging of power storage device 10 so as not to exceed the upper limit of charging current IB. Specifically, the ECU100 sets the second upper limit current Ilim2 based on the voltage applied from the power supply apparatus 300 to the inlet 70 in addition to the first upper limit current Ilim 1. Then, the ECU100 sets the smaller one of the first upper limit current Ilim1 and the second upper limit current Ilim2 as the limit current Ilim, and controls the charging of the power storage device 10 so that the current flowing through the charging cable 330 does not exceed the limit current Ilim. That is, the upper limit of the charging current IB supplied to the power storage device 10 is set based on the limit current Ilim.

In the power supply apparatus 300, for example, there are a power supply apparatus of a specification that supplies power having a voltage of 100V to the vehicle 1 and a power supply apparatus of a specification that supplies power having a voltage of 200V to the vehicle 1. The charging cable 330 generally uses a charging cable corresponding to the specification of the power supply apparatus 300.

By determining the specification of power feeding apparatus 300, the rated current of charging cable 330 used in power feeding apparatus 300 can be estimated. The specification of the power supply apparatus 300 can be determined by detecting a voltage applied from the power supply apparatus 300 to the inlet 70. When the second upper limit current Ilim2 is predetermined for each specification of the power supply apparatus 300, an appropriate second upper limit current Ilim2 that does not exceed the rated current of the charging cable 330 can be set by detecting the voltage applied from the power supply apparatus 300 to the inlet 70. The voltage applied from the power supply apparatus 300 to the inlet 70 can use, for example, the voltage VIN detected by the voltage sensor 80.

The second upper limit current Ilim2 is set by the following equation (4) when the voltage applied from the power supply apparatus 300 to the inlet 70 is 100V, for example, and is set by the following equation (5) when the voltage applied from the power supply apparatus 300 to the inlet 70 is 200V. Current I1 shown in equation (4) is a value not exceeding the rated current of the charging cable corresponding to power feeding apparatus 300 of the specification for supplying electric power having a voltage of 100V to vehicle 1. Current I2 shown in equation (5) is a value not exceeding the rated current of the charging cable corresponding to power feeding apparatus 300 of the specification that supplies power having a voltage of 200V to vehicle 1. The current I1 and the current I2 are set based on the specification of each charging cable and the like.

Ilim2＝I1…(4)

Ilim2＝I2(>I1)…(5)

As the relationship between the specification of power feeding device 300 and the rated current of the charging cable, for example, the above-described equations (4) and (5) may be stored in memory 120 of ECU100, or a map indicating the relationship between the specification of power feeding device 300 and currents I1 and I2 determined by equations (4) and (5) may be stored in memory 120 of ECU 100.

In this way, by setting the second upper limit current Ilim2 in addition to the first upper limit current Ilim1, and setting the smaller of the first upper limit current Ilim1 and the second upper limit current Ilim2 as the limit current Ilim, even if the pilot signal is offset and the first upper limit current Ilim1 is set to a value larger than the original rated current of the charging cable 330, the value of the second upper limit current Ilim2 is set for the limit current Ilim. Thus, even when the offset of the pilot signal occurs, it is possible to suppress the current exceeding the rated current of charging cable 330 from flowing to charging cable 330 during external charging, and to suppress damage to charging cable 330. The second upper limit current Ilim2 can be said to be set as a safety guard when the offset of the pilot signal occurs.

< processing for setting a limiting Current executed by the ECU >

Fig. 4 is a flowchart showing the procedure of the process for setting the limiting current Ilim executed by the ECU 100. This flowchart starts when connector 340 of charging cable 330 is connected to inlet 70 of vehicle 1. Although the case where each step (hereinafter, the step will be abbreviated as "S") of the flowchart shown in fig. 4 is realized by software processing of the ECU100 is described, a part or all of the steps may be realized by hardware (circuit) built in the ECU 100.

When the connector 340 is connected to the docking port 70 (when it is detected that the potential of the connector connection signal PISW becomes the potential V4), the ECU100 executes the processes of S1 and S5 in parallel.

Specifically, when the connector 340 is connected to the docking port 70, the ECU100 measures the Duty cycle Duty of the pilot signal CP L T (S1).

Then, the ECU100 sets the first upper limit current Ilim1 according to the Duty ratio Duty of the pilot signal CP L T (S3).

When connector 340 is connected to inlet 70, ECU100 detects the voltage applied from power supply apparatus 300 to inlet 70, and determines which of 100V and 200V the applied voltage is (S5). Specifically, the ECU100 determines which of 100V and 200V the voltage VIN detected by the voltage sensor 80 is.

The ECU100 reads out and sets the second upper limit current Ilim2 from the memory 120 based on the voltage determined in S5 (S7).

The ECU100 compares the first upper limit current Ilim1 set in S3 with the second upper limit current Ilim2 set in S7 (S9). If the first upper limit current Ilim1 is smaller than the second upper limit current Ilim2 (yes in S9), the ECU100 sets the value of the first upper limit current Ilim1 for the limit current Ilim (S11).

On the other hand, if the first upper limit current Ilim1 is equal to or greater than the second upper limit current Ilim2 (no in S9), the ECU100 sets the value of the second upper limit current Ilim2 for the limit current Ilim (S13).

In the above description, the example of "when the connector 340 is connected to the docking port 70, the ECU100 executes the processes of S1 and S3 and the processes of S5 and S7 in parallel" has been described, but the processes of S1 and S3 may be executed and then the processes of S5 and S7 may be executed, and the processes of S5 and S7 may be executed and then the processes of S1 and S3 may be executed.

As described above, ECU100 of vehicle 1 including the charging device according to the present embodiment sets second upper limit current Ilim2 based on the voltage applied from power supply apparatus 300 to inlet 70, in addition to first upper limit current Ilim 1. Then, the ECU100 sets the smaller one of the first upper limit current Ilim1 and the second upper limit current Ilim2 as the limit current Ilim, and controls the charging of the power storage device 10 so that the current flowing through the charging cable 330 does not exceed the limit current Ilim. In other words, the second upper limit current Ilim2 is set as a safety guard when the offset of the pilot signal occurs.

Thus, even if the first upper limit current Ilim1 is set to a value larger than the original rated current of the charging cable 330 due to the offset of the pilot signal, the second upper limit current Ilim2 is set to the limit current Ilim. Therefore, even when offset of the pilot signal occurs, it is possible to suppress an excessive current exceeding the rated current of charging cable 330 from flowing to charging cable 330 during external charging, and to suppress damage to charging cable 330.

While the embodiments of the present invention have been described, the embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is indicated by the claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.