Charging device

Abstract

To provide a charging device capable of discriminating between ground fault abnormality and abnormality of a ground fault detection circuit during diagnosis of the ground fault detection circuit.SOLUTION: A charging device includes: a connector connectable to an electric vehicle equipped with a power storage device; a power unit for supplying electric power to the power storage device in a state where the connector is connected to the electric vehicle; and a ground fault detector that detects a ground fault on an output circuit of electric power from the power unit to the connector, and has a ground fault detector diagnosis circuit that diagnoses the ground fault detector. The ground fault detector diagnosis circuit executes determination of presence or absence of a ground fault of a ground fault detection circuit provided inside the ground fault detector at a voltage lower than a voltage lower limit value output from the power unit when ground fault detection is monitored by the ground fault detector.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a charging device. [Background technology]

[0002] Patent Document 1 discloses a power conversion device that has a relay that switches between connection and disconnection between a battery pack and the electric vehicle in order to diagnose a ground fault detection circuit installed in the electric vehicle, and by turning on the relay when the vehicle is started, a pseudo ground fault is caused between the battery pack and the vehicle body, and the ground fault detection circuit is diagnosed based on the output of the ground fault detection circuit at this time. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-221395 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the power conversion device disclosed in Patent Document 1, if a ground fault has already occurred or if a ground fault occurs during diagnosis of the ground fault detection circuit, it is not possible to determine whether the abnormality is a ground fault or an abnormality in the ground fault detection circuit during the diagnosis.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a charging device that can distinguish between a ground fault abnormality and an abnormality in the ground fault detection circuit during diagnosis of the ground fault detection circuit. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the charging device of the present invention is a charging device comprising: a connector connectable to an electric vehicle equipped with a power storage device; a power unit for supplying power to the power storage device when the connector is connected to the electric vehicle; and a ground fault detector for detecting a ground fault on the power output circuit from the power unit to the connector, and is characterized in that it is provided with a ground fault detector diagnostic circuit for diagnosing the ground fault detector, and the ground fault detector diagnostic circuit determines whether or not a ground fault has occurred in the ground fault detection circuit provided inside the ground fault detector at a voltage lower than a lower limit voltage output from the power unit when monitoring ground fault detection by the ground fault detector. [Effects of the Invention]

[0007] The charging device according to the present invention has the advantage of being able to distinguish between a ground fault abnormality and an abnormality in the ground fault detection circuit during diagnosis of the ground fault detection circuit. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a charging device according to an embodiment. [Figure 2] FIG. 2 is a flowchart showing an example of control relating to diagnosis of the ground fault detection circuit and ground fault detection in the charging device according to the embodiment. [Figure 3] FIG. 3 is a timing chart showing an example of control relating to diagnosis of the ground fault detection circuit and ground fault detection in the charging device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the charging device according to the present invention will be described, but the present invention is not limited to the embodiment.

[0010] 1 is a diagram showing a schematic configuration of a charging device 1 according to an embodiment. The charging device 1 according to the embodiment includes a connector 2, an output circuit 3, a ground fault detector 4, a ground fault detector diagnostic circuit 5, a power unit 6, and a voltage sensor 7.

[0011] The connector 2 has a P output terminal 20P electrically connected to the power unit 6 by the power line L1 of the output circuit 3, and an N output terminal 20N electrically connected to the power unit 6 by the power line L2 of the output circuit 3, and is a charging connector that can be connected to an inlet of an electric vehicle equipped with an electricity storage device (battery) to be charged. The output circuit 3 forms a path for transmitting power output from the power unit 6 connected to a commercial power source 8 to the connector 2. The ground fault detector 4 has a power line L3 electrically connected to the power line L1 of the output circuit 3 and a power line L4 electrically connected to the power line L2 of the output circuit 3, and detects a ground fault on the power output circuit 3 from the power unit 6 to the connector 2. The ground fault detector diagnostic circuit 5 has a power line L5 electrically connected to the power line L1 of the output circuit 3 and a power line L6 electrically connected to the power line L2 of the output circuit 3, and diagnoses the ground fault detection circuit provided inside the ground fault detector 4 (determines whether a ground fault exists in the ground fault detection circuit). The power unit 6 is capable of outputting voltages for operating the ground fault detector 4 and the ground fault detector diagnostic circuit 5. The voltage sensor 7 is connected in parallel to the power lines L1 and L2 of the output circuit 3, and measures the voltage output from the power unit 6.

[0012] In the charging device 1 according to the embodiment, when monitoring the detection of a ground fault by the preset ground fault detector 4, a voltage lower than the lower limit of the ground fault detection voltage (voltage in the output voltage range) output from the power unit 6 and up to a voltage range in which self-diagnosis of the ground fault detection circuit provided inside the ground fault detector 4 is possible is applied, and the ground fault detection circuit is diagnosed by the ground fault detector diagnostic circuit 5, which determines whether or not there is a ground fault in the ground fault detection circuit. If it is determined that there is no ground fault in the ground fault detection circuit and the diagnosis result of the ground fault detection circuit is normal, the voltage is increased to the ground fault detection voltage (voltage in the output voltage range), and the detection of a ground fault on the output circuit 3 by the ground fault detector 4 is monitored.

[0013] Fig. 2 is a flowchart showing an example of control relating to diagnosis of the ground fault detection circuit and ground fault detection in the charging device 1 according to the embodiment. Fig. 3 is a timing chart showing an example of control relating to diagnosis of the ground fault detection circuit and ground fault detection in the charging device 1 according to the embodiment.

[0014] First, as shown in FIG. 2, the charging device 1 applies a voltage for self-diagnosis of the ground fault detection circuit (a voltage equal to or lower than the lower limit voltage of the output voltage range and equal to or higher than the lower limit voltage of the self-diagnosable voltage range shown in FIG. 3) from the power unit 6 (step S1). Next, the charging device 1 performs a diagnosis (self-diagnosis) of the ground fault detection circuit by using the ground fault detector diagnostic circuit 5 to determine whether or not a ground fault exists in the ground fault detection circuit provided inside the ground fault detector 4 (step S2). Next, the charging device 1 determines whether the diagnosis result of the ground fault detection circuit is normal (abnormal) (step S3). If it is determined that there is no ground fault in the ground fault detection circuit and the diagnosis result is normal (Yes in step S3), the charging device 1 applies a voltage for ground fault detection by the ground fault detector 4 from the power unit 6 (a voltage equal to or higher than the lower limit voltage of the output voltage range and equal to or lower than the upper limit voltage of the output voltage range shown in FIG. 3: a voltage within the output voltage range) (step S4). Next, the charging device 1 monitors the ground fault detection for a certain period of time (step S5). Next, the charging device 1 determines whether the ground fault detection result is normal (abnormal) (step S6). If a ground fault is not detected on the output circuit 3 and it is determined that the ground fault detection result is normal (Yes in step S6), the charging device 1 performs discharge (step S7) and then continues normal processing (step S8). Then, the charging device 1 ends the series of controls.

[0015] Furthermore, in step S3, if it is determined that there is a ground fault in the ground fault detection circuit and the diagnosis result is determined to be abnormal (not normal) (No in step S3), the charging device 1 performs discharge (step S9) and then terminates abnormally (step S10). Then, the charging device 1 terminates the series of controls.

[0016] Furthermore, in step S6, if a ground fault on the output circuit 3 is detected and the ground fault detection result is determined to be abnormal (not normal) (No in step S6), the charging device 1 performs discharge (step S9) and then terminates abnormally (step S10). Then, the charging device 1 terminates the series of controls.

[0017] A charging device 1 according to an embodiment includes a connector 2 connectable to an electric vehicle equipped with a power storage device, a power unit 6 for supplying power to the power storage device when the connector 2 is connected to the electric vehicle, and a ground fault detector 4 for detecting a ground fault on an output circuit 3 for power from the power unit 6 to the connector 2. The charging device 1 also includes a ground fault detector diagnostic circuit 5 for diagnosing the ground fault detector 4. When monitoring ground fault detection by the ground fault detector 4, the ground fault detector diagnostic circuit 5 determines whether or not a ground fault has occurred in the ground fault detection circuit provided inside the ground fault detector 4 at a voltage lower than a lower limit voltage output from the power unit 6. As a result, the charging device 1 according to an embodiment can distinguish between a ground fault abnormality on the output circuit 3 due to a failure of the connector 2 or the like and an abnormality in the ground fault detection circuit due to a failure of the ground fault detector 4 during diagnosis of the ground fault detection circuit.

[0018] Furthermore, the charging device 1 according to the embodiment can determine whether the ground fault is abnormal on the output circuit 3 or an abnormality in the ground fault detection circuit, and can transition to abnormality processing within a specified time when a ground fault is detected by the ground fault detector 4 that has applied a ground fault detection voltage (a voltage within the output voltage range). [Explanation of symbols]

[0019] 1 Charging device 2 connectors 3 Output circuit 4. Earth fault detector 5. Ground fault detector diagnostic circuit 6 Power Unit 7 Voltage Sensor 8 Commercial power supply

Claims

[Claim 1] a connector connectable to an electric vehicle equipped with the power storage device; a power unit for supplying electric power to the power storage device in a state in which the connector is connected to the electric vehicle; a ground fault detector that detects a ground fault on an output circuit of power from the power unit to the connector; A charging device comprising: a ground fault detector diagnostic circuit for diagnosing the ground fault detector; The charging device is characterized in that the ground fault detector diagnostic circuit determines whether or not a ground fault has occurred in the ground fault detection circuit provided inside the ground fault detector at a voltage lower than a lower limit voltage output from the power unit when monitoring ground fault detection by the ground fault detector.

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