JP5369833B2 - Electric vehicle charger and ground fault detection method - Google Patents

Abstract

Provided is an electric vehicle charger capable of, while rapidly charging to an electric vehicle, quickly detecting both the occurrence of a ground fault in an electric vehicle charger and the occurrence of leakage in the electric vehicle. In order to allow data communication with an electric vehicle (200) during charging, a communication earth wire (110) for connecting the negative electrode of a control system power supply (208) of the electric vehicle charger to a vehicle body earth (203) is grounded to the earth (400) via a ground wire (109). A ground fault detection device (102) of the electric vehicle charger (100) has a series circuit (1021) of resistors (1021A, 1021B) having the same resistance values and connected to positive electrode-side and negative electrode-side charging lines (103A, 103B), a ground wire (1023) for connecting a point between the resistors (1021A, 1021B) to the earth (400), a current detector (1022) for sequentially outputting the measured values of DC current flowing through the ground wire (1023), and a controller (1024) for detecting the occurrence of a ground fault in the electric vehicle charger (100) and the occurrence of leakage in the electric vehicle by comparing the measured current values output by the current detector (1022) with a threshold value.

Description

  The present invention relates to ground fault detection of an electric vehicle charger, and in particular, during the rapid charging of an electric vehicle, the ground fault detection device on the electric vehicle charger side and electric The present invention relates to a technology that can quickly detect both occurrences of electric leakage in a vehicle.

  Some electric vehicles equipped with a battery that is insulated from the vehicle body ground are provided with a capacitor-type insulation monitoring device that detects leakage from the battery to the vehicle body ground. For example, Patent Literature 1 discloses a leakage detection system that functions as such a capacitor-type insulation monitoring device. In this leakage detection system, a series circuit consisting of a capacitor, a current transformer, and an AC power source that cuts off direct current is provided between the charging line on one pole side and the vehicle body. An alternating current flowing from the power source through the capacitor and the charging line is detected by the leakage current detector via the current transformer.

  On the other hand, a charging system described in Patent Document 2 is known as a charging system that controls charging of an on-vehicle battery of an electric vehicle. In this charging system, during charging of the in-vehicle battery, the control device of the electric vehicle sequentially determines a charging reference value corresponding to the charging status of the in-vehicle battery based on a predetermined charging pattern, and notifies the charger of the charging reference value. To do. And a charger controls output electric energy based on the charge reference value received from the electric vehicle.

  Here, in order to realize communication between the charger and the electric vehicle during charging of the in-vehicle battery of the electric vehicle, in the charging cable of the charger, in addition to a charging line for supplying power to the in-vehicle battery of the electric vehicle, A communication line for communicating with the control device of the electric vehicle is accommodated. By attaching the connector at the tip of the charging cable to the electric vehicle side, the charging line on the charger side and the communication line are respectively connected to the electric vehicle side. Are connected to the power line and communication line.

Japanese Patent Laying-Open No. 2005-20848 (FIGS. 14, 15, and 16) JP 2007-336778 A

  In a capacitor-type insulation monitoring device mounted on an electric vehicle, generally, a filtering process by a fast Fourier transform is performed in order to discriminate a minute alternating current and noise that flow when an electric leakage occurs. In order to identify AC current and noise that flows when leakage occurs by fast Fourier transform, it is necessary to sample data over a certain amount of time, and accordingly, it takes time to detect AC current that flows when leakage occurs.

  By the way, in a quick charger that rapidly charges an in-vehicle battery of an electric vehicle, a ground fault is monitored on the quick charger side during the rapid charging of the in-vehicle battery of the electric vehicle. It is designed to be blocked. It is desired that the occurrence of electric leakage on the electric vehicle side be detected more quickly during the rapid charging of the on-vehicle battery of the electric vehicle.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to quickly detect both the occurrence of a ground fault in an electric vehicle charger and the occurrence of electric leakage in an electric vehicle during charging of the electric vehicle. An object of the present invention is to provide an electric vehicle charger.

  In order to solve the above-described problem, in the present invention, in the battery charger for electric vehicles, while inserting resistances having equal resistance values between the charging line and the ground (ground) on the positive electrode side and the negative electrode side, In order to realize data communication with the other electric vehicle, an existing communication ground wire that connects the negative electrode of the power supply of the controller for the electric vehicle charger to the vehicle body ground is grounded. During charging of the electric vehicle, on the electric vehicle charger side, the DC current between the charging line and the ground on the positive electrode side and the negative electrode side via the resistor is sequentially measured by the detector, and the measurement is performed. Monitor value fluctuations.

For example, according to the present invention, during charging of the electric vehicle, the negative electrode of the first power source that supplies power to the control device is connected to the vehicle body ground of the electric vehicle by a communication ground wire, and the electric vehicle and the control device are connected to each other. An electric vehicle charger for realizing data communication,
A positive electrode side and a negative electrode side charging line for supplying power to the in-vehicle battery of the electric vehicle;
A series circuit composed of two resistors having the same resistance value, inserted between the positive and negative charging lines;
A first grounding wire connecting the grounding position defined between the two resistors to the ground;
A second ground wire connecting the communication ground wire to the ground;
Detecting means for detecting a current flowing in the first ground line, or a voltage between the ground position and the ground,
The controller is
Based on the detection value of the detection means, the occurrence of a ground fault in the charging line on either the positive electrode side or the negative electrode side and the occurrence of electric leakage in the electric vehicle are detected.

Alternatively, according to the present invention, during charging of the electric vehicle, the negative electrode of the first power source that supplies power to the control device is connected to the vehicle body ground of the electric vehicle by a communication ground wire, and the electric vehicle and the control device are connected to each other. An electric vehicle charger for realizing data communication,
A positive electrode side and a negative electrode side charging line for supplying power to the in-vehicle battery of the electric vehicle;
A series circuit composed of two resistors having the same resistance value, inserted between the positive and negative charging lines;
A first grounding wire connecting the grounding position defined between the two resistors to the ground;
A second ground wire connecting the communication ground wire to the ground;
Detection means for detecting a current flowing through the first ground line or a voltage between the ground position and the ground;
And a controller for detecting a ground fault occurrence in the charging line on either the positive electrode side or the negative electrode side and a leakage occurrence in the electric vehicle based on a detection value of the detection means.

  When such an electric vehicle charger is provided with a circuit breaker that interrupts at least one of the positive electrode side and the negative electrode side charging line, and the control device detects the occurrence of the ground fault or the electric leakage, the positive electrode side The circuit breaker may be instructed to interrupt at least one of the negative-side charging line.

  In addition, the electric vehicle charger is provided with a second power source insulated from the ground, and the control device is supplied with power from the first power source to perform data communication with the electric vehicle. A communication system circuit unit to be executed; a control system circuit unit which is supplied with power from the second power source and executes control processing of the electric vehicle charger; and data between the control system circuit unit and the communication system circuit unit Relay means for performing contact-free transfer.

  According to the present invention, during charging of an electric vehicle, the electric vehicle charger can more quickly detect both the occurrence of a ground fault in the electric vehicle charger and the occurrence of electric leakage in the electric vehicle.

FIG. 1 is a diagram for explaining a schematic configuration of a charger for an electric vehicle according to an embodiment of the present invention. FIG. 2A is a diagram showing a flow of a ground fault current when a ground fault occurs in the negative electrode side charging line of the electric vehicle charger in FIG. 1, and FIG. FIG. 2 is a diagram showing a flow of a ground fault current when a ground fault occurs in the positive electrode side charging line of the electric vehicle charger. FIG. 3A is a diagram illustrating a flow of a leakage current when a leakage occurs in the negative electrode side charging line of the electric vehicle during the rapid charging by the electric vehicle charger in FIG. B) is a diagram illustrating a flow of a leakage current when a leakage occurs in the positive electrode charging line of the electric vehicle during the rapid charging by the electric vehicle charger in FIG. 1. FIG. 4 is a diagram for explaining a schematic configuration of a charger for an electric vehicle with a countermeasure against surge according to another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  First, the configuration of the electric vehicle charger according to the present embodiment will be described. Here, an explanation will be given by taking as an example a quick charger that is installed in a charging stand or the like and that rapidly charges an in-vehicle battery of an electric vehicle.

  FIG. 1 is a diagram showing a schematic configuration of an electric vehicle charger 100 according to the present embodiment. FIG. 1 shows an example in which the contact connector 101 of the electric vehicle charger 100 is attached to the contact connector 201 on the electric vehicle 200 side.

  As shown in the figure, the electric vehicle charger 100 includes a control device 104, a control system power supply 108, an electric leakage breaker (ELB) 105, an AC / DC converter 103, a charging cable 106, a contact connector 101, Have

The control device 104 controls the entire electric vehicle charger 100. The control system power supply 108 supplies 12V power to the control device 104. The earth leakage breaker (ELB) 105 is connected to a lead-in cable for an AC power supply (for example, 200 V) 300, and the AC / DC converter 103 converts the AC current supplied from the AC power supply 300 via the earth leakage breaker 105 to the DC current I. Convert to ₁ . Here, the configuration of the earth leakage circuit breaker 105 that disconnects both the positive electrode side and negative electrode side outputs (positive electrode side and negative electrode side charging lines 103A and 103B) of the AC power source 300 from the AC power source 300 is illustrated. The device 105 may be configured to disconnect one of the positive electrode side and negative electrode side charging lines 103 </ b> A and 103 </ b> B from the AC power supply 300. The charging cable 106 accommodates the positive and negative charging lines 103 </ b> A and 103 </ b> B from the AC / DC converter 103. The contact connector 101 is provided at the tip of the charging cable 106.

  In order to realize communication with control device 204 of electric vehicle 200 during rapid charging, charging cable 106 further accommodates communication line 107 from control device 104 and communication ground wire 110. The communication ground wire 110 is for connecting the negative electrode of the control system power supply 108 to the vehicle body ground 203. The vehicle body ground 203 is connected to a negative electrode of a control system power source 208 that supplies a 12V power source to the control device 204 of the electric vehicle 200.

  Therefore, by connecting the contact connector 101 of the electric vehicle charger 100 to the contact connector 201 on the electric vehicle 200 side, the positive and negative charging lines 103A and 103B of the electric vehicle charger 100 are Not only the positive and negative charge lines 206A and 206B on the electric vehicle 200 side, but also the terminal of the communication line 107 and the terminal of the communication line 207 on the electric vehicle 200, and the charger for the electric vehicle. 100 terminals of the communication ground line 110 and terminals of the communication ground line 205 on the electric vehicle 200 side are respectively connected.

  Further, the electric vehicle charger 100 also monitors for a ground fault in the positive and negative charging lines 103A and 103B during the rapid charging of the in-vehicle battery 202 of the electric vehicle 200, as well as leakage in the electric vehicle 200. It has the structure for doing. Specifically, the grounding wire 109 that connects the communication grounding wire 110 to the ground (ground) 400 on the electric vehicle charger 100 side, the occurrence of ground faults in the positive and negative charging lines 103A and 103B, and the electric vehicle And a ground fault detection device 102 that detects both occurrences of electric leakage in 200.

  Here, the ground fault detection device 102 includes a series circuit 1021 composed of two resistors 1021A and 1021B having the same resistance value inserted between the positive-side charging line 103A and the negative-side charging line 103B, and between the resistors 1021A and 1021B. A suitable position (for example, a position where resistance is equally divided into two, hereinafter referred to as a ground connection point) 1021C to the ground (ground) 400, and a measured value of a direct current flowing through the ground line 1023 Current detector 1022 such as a current transformer (DC CT) that sequentially outputs and a controller 1024 to which a measured value of the current detector 1022 is input.

  That is, resistors 1021A and 1021B having the same resistance value are inserted between the positive side charging line 103A and the ground 400 and between the negative side charging line 103B and the ground 400, respectively, to the in-vehicle battery 202 of the electric vehicle 200. During the quick charging, the current detector 1022 causes the ground fault current (the DC current between the positive charging line 103A and the ground 400, the DC current between the negative charging line 103B and the ground 400, via the resistors 1021A and 1021B. Between the positive side charging line 206A on the electric vehicle 200 side and the vehicle body ground 203 (= earth 400), and between the negative side charging line 206B on the electric vehicle 200 side and the vehicle body ground 203 (= earth 400). DC current) is measured sequentially, and the controller 1024 monitors the fluctuation of the measured value. You have me.

  Here, as the two resistors 1021A and 1021B, it is necessary to use a resistor that suppresses an abnormal current that flows when a ground fault occurs. In addition, if the resistance values of the resistors 1021A and 1021B become too large, the current detection time becomes long. Therefore, when determining the resistance values of the resistors 1021A and 1021B, it is necessary to consider the performance of the current detector 1022 to be used. . For these reasons, for example, in the case of an AC power supply of 200 V, it is preferable to determine the resistance values of the resistors 1021A and 1021B within a range of several tens of kΩ to several hundreds of kΩ.

  Next, the detection principle of the occurrence of ground fault and electric leakage during the rapid charging of the in-vehicle battery 202 of the electric vehicle 200 by the electric vehicle charger 100 will be described. Here, first, detection of ground fault on the electric vehicle charger 100 side will be described, and then detection of electric leakage on the electric vehicle 200 side will be described.

  FIG. 2A is a diagram illustrating a flow of a ground fault current when a ground fault occurs in the negative electrode side charging line 103B of the electric vehicle charger 100, and FIG. It is a figure which shows the flow of a ground fault electric current when a ground fault generate | occur | produces in the positive electrode side charging line 103A of the device 100. FIG. In these figures, only the configuration of the closed circuit portion through which the ground fault current flows is shown, and the other configurations are omitted.

By attaching the contact connector 101 of the electric vehicle charger 100 to the contact connector 201 on the electric vehicle 200 side, the terminals of the positive and negative charging lines 103A and 103B of the electric vehicle charger 100 are connected to the electric vehicle. When the DC current I ₁ is supplied from the electric vehicle charger 100 to the in-vehicle battery 202 of the electric vehicle 200 by connecting to the terminals of the positive electrode side and negative electrode side charging lines 206A and 206B of the electric vehicle 200 (see FIG. 1), the electric vehicle Rapid charging of 200 in-vehicle batteries 202 starts. In this state, since the voltages applied to the two resistors 1021A and 1021B having the same resistance value are balanced, the ground connection point 1021C and the ground 400 have the same potential (0 V), and no direct current flows through the ground line 1023. .

Here, as shown in FIG. 2A, when a ground fault occurs at an arbitrary position (ground fault point) P1 of the negative electrode side charging line 103B of the electric vehicle charger 100, the ground 400 is charged for negative side charging. ground fault current _{I 2} flowing into the land絡点P1 line 103B flows into the ground 400 via the AC-DC converter 103, the positive electrode side charging line 103A, one of the resistors 1021A and the ground line 1023. Therefore, the current detector 1022 detects the ground fault current _{I 2.}

On the other hand, as shown in FIG. 2B, when a ground fault occurs at an arbitrary position (ground fault point) P2 of the positive-side charging line 103A of the electric vehicle charger 100, the ground of the positive-side charging line 103A is obtained. ground fault current _{I 3} flowing into the earth 400 from絡点P2 is a ground line 1023 flows to the AC-DC converter 103 via the other resistor 1021B and the negative electrode side charging line 103B. Therefore, the current detector 1022 detects the ground fault current _{I 3.}

  FIG. 3A is a diagram illustrating a flow of a leakage current when a leakage occurs in the negative electrode side charging line 206 </ b> B of the electric vehicle 200, and FIG. 3B is a positive electrode side charging line of the electric vehicle 200. It is a figure which shows the flow of the earth leakage current when the earth leakage occurs in 206A. In these figures, only the configuration of the closed circuit portion through which the leakage current flows is shown, and the other configurations are omitted.

  As described above, while the rapid charging of the in-vehicle battery 202 of the electric vehicle 200 is normally performed, in the ground fault detection device 102, the voltages applied to the two resistors 1021A and 1021B having the same resistance value are balanced. Therefore, no direct current flows through the ground line 1023.

Here, as shown in FIG. 3A, if a leakage occurs at an arbitrary position (leakage point) P3 of the negative electrode side charging line 206B of the electric vehicle 200, the electric leakage of the negative electrode side charging line 206B from the vehicle body ground 203 will be described. Leakage current I ₄ flowing into point P3 is connected to ground 400 via positive electrode side charging line 206A, positive electrode side charging line 103A of electric vehicle charger 100, one resistance 1021A of ground fault detection device 102 and ground line 1023. And return to the vehicle body ground 203 via the ground line 109 of the control system power supply 108 and the communication ground lines 110 and 205. That is, the power supply ground of the control device 104 is originally not shared with the ground 400, but in this embodiment, the negative side of the control system power supply 108 that supplies power to the control device 104 is grounded to the ground 400. Since the grounding wire 109 to be provided is shared and the power supply ground of the control device 104 and the earth 400 to which the ground fault detection device 102 is connected are shared, the earth leakage current I ₄ generated on the electric vehicle 200 side becomes a ground fault. A route is formed through the ground line 1023 of the detection device 102, the ground line 109 of the control system power supply 108, and the communication ground lines 110 and 205. Therefore, the current detector 1022 of the ground fault sensing device 102 detects the leakage current _{I 4.}

On the other hand, as shown in FIG. 3B, when a leakage occurs at an arbitrary position (leakage point) P4 of the positive electrode side charging line 206A of the electric vehicle 200, the vehicle body is grounded from the leakage point P4 of the positive electrode side charging line 206A. Leakage current I ₅ that has flowed into 203 flows into ground 400 of electric vehicle charger 100 via communication ground lines 205 and 110 and ground line 109 of control system power supply 108, and further, It returns to the vehicle body ground 203 through the other resistor 1021B and the negative-side charging line 103B of the electric vehicle charger 100. That is, the power ground of the control device 104 is originally not shared with the ground 400. In the present embodiment, the ground wire 109 is provided as described above, and the power ground of the control device 104 and the ground are grounded. By sharing the ground 400 to which the fault detection device 102 is connected, the leakage current I ₅ generated on the electric vehicle 200 side causes the communication ground lines 110 and 205, the ground line 109 of the control system power supply 108, and the ground fault. A route passing through the ground line 1023 of the detection device 102 is formed. Therefore, the current detector 1022 of the ground fault sensing device 102 detects the earth leakage current _{I 5.}

  As can be seen from the above, during the rapid charging of the in-vehicle battery 202 of the electric vehicle 200, not only the occurrence of a ground fault in the charging line 103A, 103B on either the positive electrode side or the negative electrode side of the electric vehicle charger 100, The occurrence of leakage in the charging lines 206A and 206B on either the positive electrode side or the negative electrode side of the electric vehicle 200 can also be detected from the measured value of the current detector 1022.

  Therefore, in the present embodiment, in the electric vehicle charger 100, the controller 1024 monitors the measurement values sequentially input from the current detector 1022 during the rapid charging of the in-vehicle battery 202 of the electric vehicle 200, and If the measured value exceeds a predetermined threshold value, it is determined that a ground fault on the electric vehicle charger 100 side or an electric leakage on the electric vehicle 200 side has occurred, and an abnormal signal indicating the occurrence of a ground fault or the like is transmitted to the control device 104. Send to. In response to this, the control device 104 interrupts the circuit under the control of the leakage breaker 105. Further, the control device 104 transmits a message notifying the occurrence of a ground fault on the electric vehicle charger 100 side or an electric leakage on the electric vehicle 200 side to the control device 204 of the electric vehicle 200 via the communication lines 107 and 207. To do. In the case where the electric vehicle charger 100 has an output device, the control device 104 may output a report to the administrator or the like from the output device.

  The embodiment of the present invention has been described above.

Thus, according to the electric vehicle charger 100 according to the present embodiment, during the rapid charging of the electric vehicle 200, when a ground fault occurs on the electric vehicle charger 100 side, the current detection of the ground fault detection device 102 is performed. Since the device 1022 detects a current of about 0.1 to several mA, it is possible to immediately detect the occurrence of a ground fault by directly comparing this measured value with a threshold value. In addition, an existing communication ground wire 110 for common reference potential between the control device 204 of the electric vehicle 200 and the control device 104 of the electric vehicle charger 100 is grounded by the ground wire 109 on the electric vehicle charger 100 side. Since a ground is connected to 400, a loop is formed in which abnormal currents I ₄ and I ₅ generated on the electric vehicle 200 side return to the electric vehicle 200 side via the current detector 1022 of the ground fault detection device 102. The occurrence of electric leakage in the electric vehicle 200 being charged can be immediately detected by comparing the measured value of the current detector 1022 of the ground fault detection device 102 with a threshold value. For this reason, it is not necessary to perform arithmetic processing such as FFT, which requires a certain amount of time, and accordingly, the ground fault of the electric vehicle charger 100 and the electric leakage of the electric vehicle 200 are detected and the circuit is shut off. be able to. As a result, the time required for circuit interruption can be further shortened.

  In addition, when a noise removing capacitor for bypassing noise generated in the AC / DC converter 103 to the ground 400 is provided on the positive and negative charging lines 103A and 103B of the electric vehicle charger 100, it is assumed to be conventional. When the capacitor-type insulation monitoring device is applied as it is as the ground fault detection device of the charger 100 for an electric vehicle, the AC current generated from the AC power source of the ground fault detection device circulates between the capacitor of the insulation monitoring device and the noise removal capacitor. There is a possibility that. When such alternating current circulation occurs, there is a possibility that the leakage is erroneously detected even though the leakage does not actually occur. However, since the ground fault detection apparatus 102 according to the present embodiment does not include an element that interferes with the noise removing capacitor of the electric vehicle charger 100, the ground fault detection apparatus 102 is different from other elements of the electric vehicle charger 100. Occurrence of false ground fault detection due to interference can be prevented.

  Therefore, according to the present embodiment, the ground fault of electric vehicle charger 100 and the electric leakage of electric vehicle 200 during rapid charging of electric vehicle 200 can be detected more quickly, and the reliability of the detection can be improved. Can do.

  Moreover, during the rapid charging of the electric vehicle 200, not only the ground fault occurs in the positive and negative charging lines 103A and 103B of the electric vehicle charger 100, but also the positive and negative charging lines 206A, The occurrence of electric leakage in 206B can also be detected based on the measurement value of one current detector 1022, and therefore, a cheaper electric vehicle charger 100 can be realized.

  In the above description, the DC current between the ground connection point 1021C and the ground 400 is detected by the current detector 1022, but the voltage between the ground connection point 1021C and the ground 400 may be detected by a voltage detector. In this case, the ground line 1023 needs to have at least a resistance sufficient to detect a voltage between the ground connection point 1021C and the ground 400.

  In the above description, the controller 1024 that determines the occurrence of a ground fault based on the measurement value of the current detector 1022 is provided in the ground fault detection device 102. For example, the control device 104 measures the current detector 1022. The input of a value may be sequentially received, and the occurrence of a ground fault may be determined by comparing the measured value with a threshold value (the same applies below).

  By the way, in the present embodiment, the communication ground line 110 for common reference potential between the control device 204 of the electric vehicle 200 and the control device 104 of the electric vehicle charger 100 is connected to the ground 400 of the electric vehicle charger 100. Is grounded. For this reason, it may be necessary to consider the influence of a surge or the like on the control device 104 of the electric vehicle charger 100. Hereinafter, the configuration of the charger for an electric vehicle provided with a countermeasure against surge will be described focusing on the difference from the charger 100 for the electric vehicle described above.

  FIG. 4 is a diagram for explaining a schematic configuration of an electric vehicle charger 100A that has taken a surge countermeasure. In FIG. 4, the same reference numerals as those in FIG. 1 are assigned to the same configurations as those of the electric vehicle charger 100 described above.

  As illustrated, the control device 104A of the electric vehicle charger 100A includes a control system circuit unit 1042 that executes control processing of the entire electric vehicle charger 100A and a communication system that executes data communication processing with the electric vehicle 200. The circuit unit 1041 includes a photocoupler 1043 that connects the data transfer line of the control system circuit unit 1042 and the data transfer line of the communication system circuit unit 1041. That is, in the control device 104A, the control system circuit unit 1042 and the communication system circuit unit 1041 realize mutual data communication in a non-contact (electrically separated) state.

  The electric vehicle charger 100 </ b> A further includes another control system power supply 108 </ b> A floating from the ground 400 independently of the control system power supply 108 in which the negative electrode is connected to both the ground line 109 and the communication ground line 110. ing. The control system power supply 108 supplies 12 V power to the communication system circuit unit 1041, and the control system power supply 108 A supplies 12 V power to the control system circuit unit 1042. Other configurations are the same as those of the electric vehicle charger 100 described above.

  According to such a configuration, it is possible to float the control system circuit unit 1042 from the ground 400 while enabling data communication between the control system circuit unit 1042 and the control device 204 of the electric vehicle 200. For this reason, as with the electric vehicle charger 100 described above, the ground fault detection device 102 not only detects the occurrence of a ground fault in the electric vehicle charger 100A during the rapid charging, but also in the electric vehicle 200 during the rapid charging. The occurrence of electric leakage can also be detected using the communication ground wires 110 and 205 and the ground wire 109. In addition to this, the influence of a surge or the like on the control device 104 of the electric vehicle charger 100 can be prevented.

  Note that here, the data transfer line of the control system circuit unit 1042 and the data transfer line of the communication system circuit unit 1041 are connected by the photocoupler 1043, but between the control system circuit unit 1042 and the communication system circuit unit 1041. What is necessary is just to be able to realize the data transfer in a non-contact manner and to connect the two. For example, the data transfer line of the control system circuit unit 1042 and the data transfer line of the communication system circuit unit 1041 may be connected by a non-contact type relay.

  Further, the present invention can be widely applied not only to electric vehicles but also to electric vehicles having a charging function from an external power source of a mounted battery.

DESCRIPTION OF SYMBOLS 100,100A: Charger for electric vehicles, 101: Contact type connector, 102: Ground fault detection device, 103: AC / DC converter, 103A: Positive side charging line, 103B: Negative side charging line, 104, 04A: Control Device: 105: Earth leakage breaker (ELB), 106: Charging cable, 107: Communication line, 108: Control system power supply, 108A: Control system power supply, 109: Ground line, 110: Communication ground line, 200: Electric vehicle, 201: contact type connector, 202: vehicle-mounted battery, 203: vehicle body ground, 204: control device, 205: communication ground wire, 206A: positive side charging line, 206B: negative side charging line, 207: communication line, 208 : Control system power supply, 300: AC power supply, 400: ground, 1021A, 1021B: resistance, 1021: series circuit of resistance, 1022: electricity Detector, 1023: ground line, 1024: controller, 1041: communication circuits unit, 1042: control system circuit unit, 1043: photocoupler

Claims (5)

During charging of the electric vehicle, the negative electrode of the first power source that supplies power to the control device is connected to the vehicle body ground of the electric vehicle by a communication ground wire to realize data communication between the electric vehicle and the control device. A vehicle charger,
A positive electrode side and a negative electrode side charging line for supplying power to the in-vehicle battery of the electric vehicle;
A series circuit composed of two resistors having the same resistance value, inserted between the positive and negative charging lines;
A first grounding wire connecting the grounding position defined between the two resistors to the ground;
A second ground wire connecting the communication ground wire to the ground;
Detection means for detecting a current flowing through the first ground line or a voltage between the ground position and the ground;
With
The controller is
An electric vehicle charger characterized by detecting occurrence of a ground fault in the charging line on either the positive electrode side or the negative electrode side and occurrence of electric leakage in the electric vehicle based on a detection value of the detection means. During charging of the electric vehicle, the negative electrode of the first power source that supplies power to the control device is connected to the vehicle body ground of the electric vehicle by a communication ground wire to realize data communication between the electric vehicle and the control device. A vehicle charger,
A positive electrode side and a negative electrode side charging line for supplying power to the in-vehicle battery of the electric vehicle;
A series circuit composed of two resistors having the same resistance value, inserted between the positive and negative charging lines;
A first grounding wire connecting the grounding position defined between the two resistors to the ground;
A second ground wire connecting the communication ground wire to the ground;
Detection means for detecting a current flowing through the first ground line or a voltage between the ground position and the ground;
An electric vehicle comprising: a controller for detecting a ground fault in the charging line on either the positive electrode side or the negative electrode side and an electric leakage occurrence in the electric vehicle based on a detection value of the detection means. Charger. The electric vehicle charger according to claim 1 or 2,
A circuit breaker that further cuts off at least one of the positive electrode side and negative electrode side charging lines;
The controller is
An electric vehicle charger characterized by instructing the circuit breaker to cut off at least one of the positive electrode side and negative electrode side charging lines when the ground fault or the electric leakage occurs. The electric vehicle charger according to any one of claims 1, 2, and 3,
A second power source insulated from the ground;
The controller is
A communication system circuit unit that is supplied with power from the first power source and performs data communication with the electric vehicle;
A control system circuit unit that is supplied with power from the second power source and executes control processing of the electric vehicle charger;
And a relay device that performs non-contact data transfer between the control system circuit unit and the communication system circuit unit. Charging for an electric vehicle that realizes data communication between the electric vehicle and the control device by connecting a negative electrode of a power source that supplies power to the control device to a vehicle body ground of the electric vehicle via a communication ground wire during charging of the electric vehicle A ground fault detection method for detecting the occurrence of a ground fault in the positive and negative charge lines for supplying power to the electric vehicle and the occurrence of a leakage in the electric vehicle side,
In the electric vehicle charger, a series circuit composed of two resistors having the same resistance value is inserted between the positive electrode side and the negative electrode side charging line, and a grounding position defined between the two resistors is defined as a first ground line. And detecting means for detecting the current flowing through the first ground line or the voltage between the ground position and the ground, and connecting the ground line for communication to the ground with a second ground line. Set up
The controller or the controller provided in the charger for the electric vehicle separately from the controller is a current flowing through the first ground line that is sequentially detected by the detection means during charging of the electric vehicle. Alternatively, the ground fault and the occurrence of the electric leakage are detected based on a measured value of the voltage between the grounding position and the ground.

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