JP2014023236A - Charge monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charge monitoring device which can stop charging even in the case when relay contacts are welded.SOLUTION: A charge monitoring device 20 comprises: feeders (L, N) for connecting a breaker 11 and a charger 40 mounted on a vehicle; a relay device 22 including relay contacts (RY1-1, RY1-2) inserted in the feeders; a weld detector for detecting welding of the relay contacts (RY1-1, RY1-2); and switch devices (S3, S4) which are to be closed so as to activate a circuit configured to flow current at or above a threshold into the breaker 11, when the welding of the relay contacts are detected. The charge monitoring device 20 closes the switch devices (S3, S4) to open the breaker 11 when the welding of the relay contacts are detected, thereby, stops feeding of electric power from an external power source.

Description

  The present invention relates to a charge monitoring device interposed (inserted) between the external power source and the vehicle when charging a power storage device mounted on the vehicle using electric power supplied from an external power source.

  An electric vehicle or a hybrid vehicle is equipped with a power storage device (for example, a battery) for supplying electric power to the electric motor. These vehicles can charge the power storage device with electric power supplied from an external power source (power source outside the vehicle). The external power source is, for example, a commercial power source. For the sake of convenience, charging of the power storage device with power supplied from an external power supply is also referred to as “external charging”.

  By the way, during the period of external charging, it is detected whether or not electric leakage has occurred, and when electric leakage has occurred, measures such as stopping external charging by opening the relay contacts are performed. This is very important. Therefore, one of the conventional devices detects AC leakage using a zero-phase current transformer, and connects each of a pair of power lines connecting an “external power source” and a “circuit unit that converts AC to DC”. DC leakage is detected based on the difference between the flowing DC currents (see, for example, Patent Document 1).

JP 2000-270463 A (FIG. 1)

  However, when the relay contacts are welded, there is a problem that the leakage continues unless the user physically disconnects the connection between the external power source and the circuit unit. One of the objects of the present invention is to provide a charge monitoring device capable of terminating charging even when relay contacts are welded.

  In order to achieve the above object, a charge monitoring apparatus according to the present invention is used when charging a power storage device mounted on a vehicle using AC power supplied from an external power source. More specifically, this charge monitoring device is described as “a circuit breaker that breaks the path when a current of a predetermined threshold or more flows through the path (current path) (leakage circuit breaker, facility side leakage breaker). ) "To charge the power storage device mounted on the vehicle using AC power supplied from an external power source, the circuit breaker, the charger mounted on the vehicle and connected to the power storage device, Inserted between.

Furthermore, this charge monitoring device
A power supply line connecting the circuit breaker and the charger;
A relay device including a relay contact inserted in the feeder line;
A welding detector for detecting welding of the relay contact;
A switch device that is closed to establish a circuit configured to allow a current greater than or equal to the threshold value to flow in the path of the circuit breaker when welding of the relay contact is detected;
Is provided.

  According to this, when the welding of the relay contact is detected, the switch device is closed, so that a current equal to or greater than the threshold value flows in the circuit breaker path. Therefore, since the circuit breaker operates (opens the power feeding path), the supply of power from the external power source to the charger is stopped. As a result, even if the relay contact is welded, it is possible to avoid the leakage of electric current.

When the power supply line is a pair of connection lines connected to each of the pair of output terminal portions of the circuit breaker and each of the pair of input terminal portions of the charger, the charge monitoring device according to the present invention,
Furthermore,
A signal acquisition unit that acquires a difference detection signal that is a signal corresponding to a difference in magnitude of a current flowing through each of the pair of connection lines;
It is determined whether or not a DC leakage has occurred based on a value corresponding to the magnitude of the first signal obtained by performing low-pass filter processing on the difference detection signal, and for the difference detection signal A leakage monitoring unit that determines whether or not AC leakage has occurred based on a value corresponding to the magnitude of the second signal obtained by performing the band-pass filter processing;
Can be provided.

  When leakage occurs, the difference in the magnitude of the current flowing through each of the pair of connection lines (power lines) (that is, the magnitude of the difference detection signal) increases.

  Further, if the leakage is a DC leakage, the difference detection signal includes a large DC component. This direct current component can be extracted by a low-pass filter that passes only a signal in a predetermined low frequency range. Therefore, as in the above configuration, it is determined whether or not a DC leakage has occurred by using a value corresponding to the magnitude of the first signal obtained by performing the low-pass filter process on the difference detection signal. Can do.

  In addition, if the leakage is an AC leakage, the difference detection signal includes a large AC component. This AC component can be extracted by a band-pass filter (or a high-pass filter) that passes only a signal in a predetermined frequency band. Therefore, as in the above-described configuration, it is determined whether or not AC leakage has occurred based on a value corresponding to the magnitude of the second signal obtained by performing bandpass filter processing on the difference detection signal. be able to.

  Furthermore, according to this configuration, it is possible to distinguish whether the leakage is a DC leakage or an AC leakage with a simple circuit configuration without using a zero-phase current transformer or the like required by the prior art.

  Other objects, other features and attendant advantages of the present invention will be readily understood from the description of the embodiments of the present invention described with reference to the following drawings.

FIG. 1 is a schematic diagram of a charge monitoring apparatus according to an embodiment of the present invention and a charging system to which the charge monitoring apparatus is applied. FIG. 2 is a schematic diagram showing a connection relationship between an external power supply (commercial power supply) and the charge monitoring apparatus shown in FIG. FIG. 3 is a flowchart showing a routine executed by the CPU of the charge monitoring apparatus shown in FIG. FIG. 4 is a diagram for explaining a method for calculating the effective value of the current. FIG. 5 is a flowchart showing a routine executed by the CPU of the charge monitoring apparatus shown in FIG. FIG. 6 is a flowchart showing a routine executed by the CPU of the charge monitoring apparatus shown in FIG. FIG. 7 is a flowchart showing a routine executed by the CPU of the charge monitoring apparatus shown in FIG. FIG. 8 is a circuit diagram showing a leakage generation path. FIG. 9 is a circuit diagram showing a leakage generation path. FIG. 10 is a circuit diagram showing a leakage generation path. FIG. 11 is a circuit diagram showing a leakage generation path. FIG. 12 is a circuit diagram showing a leakage generation path. FIG. 13 is a circuit diagram illustrating a leakage generation path. FIG. 14 is a flowchart showing a routine executed by the CPU of the charge monitoring apparatus shown in FIG.

  Hereinafter, a charge monitoring apparatus according to an embodiment of the present invention will be described with reference to the drawings. This charge monitoring device is used when a power storage device (storage battery) mounted in a hybrid vehicle (so-called plug-in hybrid vehicle) is charged with electric power from an external power source. This charge monitoring device can also be applied to an electric vehicle. Hereinafter, “a vehicle equipped with a power storage device that can be charged with electric power from an external power source, such as a hybrid vehicle and an electric vehicle” is simply referred to as “EV”.

(Constitution)
As shown in FIG. 1, the charge monitoring device 20 according to the embodiment of the present invention is interposed (inserted) between the external power supply 10 and the in-vehicle charger 40. The external power supply 10 and the charge monitoring device 20 are connected to each other by the first connector Co1. The charge monitoring device 20 and the in-vehicle charger 40 are connected by the second connector Co2. The on-vehicle charger 40 is connected to a power storage device 50 mounted on the hybrid vehicle.

<External power supply>
The external power supply 10 is a commercial power supply. The external power source 10 supplies AC 200 V (AC 200 V) power between the first power supply line L and the second power supply line N. The second feeder line N is connected to the ground (FG: frame ground). “To be connected to the ground” is also expressed as “to be grounded”.

  The external power supply 10 includes an earth leakage breaker (breaker, EV dedicated earth leakage breaker, EV charging dedicated earth leakage breaker) 11. The earth leakage breaker 11 includes a pair of relay contacts (RY0-1, RY0-2). The earth leakage breaker 11 automatically opens the relay contacts (RY0-1, RY0-2) when a current exceeding a threshold value (for example, 15 mA) flows for a predetermined time (for example, 100 ms), thereby external power 10 ”constitutes a cutoff unit (leakage cutoff unit) that cuts off the supply of power from 10. The output side of the relay contacts (RY0-1, RY0-2) of the earth leakage breaker 11 constitutes a pair of output terminal portions (a1, a2). That is, the external power supply 10 supplies AC power to the pair of output terminal portions (a1, a2) through the leakage breaker 11.

  As shown in FIG. 2, the earth leakage breaker 11 is inserted between the “hand switch 12 installed outdoors” and the “indoor distribution board 13”. The distribution board 13 is connected to a transformer Tr that converts high-voltage (for example, 6600 V) power transmitted from a power plant or the like through a transmission line HV into low-voltage (for example, 200 V) power. The electric power supplied from the transformer Tr is supplied to home appliances (such as a TV, an air conditioner, and a cooking appliance) through each of the ampere breaker 13a, the main leakage breaker 13b, and the plurality of branch breakers 13c. Furthermore, the electric power supplied from the transformer Tr is supplied to the hand switch 12 through the above-described leakage breaker 11.

  The hand switch 12 is configured to be able to be switched on and off by a manual operation by an operator. The hand switch 12 is covered with a drip-proof case 12a. The hand switch 12 is connected to an EV charging outdoor outlet 14. The outdoor outlet 14 is connected to the “connecting portion 15 connected to the charging monitoring device 20 via the power cable DK1”. Accordingly, the “EV charging outdoor outlet 14 and connecting portion 15” constitute the first connector Co1 described above. The charge monitoring device 20 is connected to the second connector Co2 in the operation unit S via the power cable DK2. The operation unit S is inserted into an inlet exposed on the side surface of the vehicle (not shown), whereby the second connector Co2 is connected to the in-vehicle charger 40 of the vehicle.

<Charge monitoring device>
Referring to FIG. 1 again, the charge monitoring device 20 includes a hall sensor 21, a relay (relay device) 22, resistors R1-R4, switches S1-S4, an amplifier 23, an AD converter 24, a filter unit 25, a control unit 26, An AC-DC insulated power supply 27, a first low-pass filter 28, a gain setting device 29, an alarm device (buzzer and LED) 30, and the like are included.

  The hall sensor 21 determines the “magnitude of current flowing through the first power supply line L (first connection line) in the charge monitoring device 20” and the “second power supply line N (second connection line) in the charge monitoring device 20. A current difference detection device is configured to generate a voltage (voltage signal V) corresponding to the difference in the “current magnitude”. That is, the Hall sensor 21 has a magnitude of the current IL that flows through the first power supply line L from the external power supply 10 side to the in-vehicle charger 40 side, and the second power supply line N from the in-vehicle charger 40 side to the external power supply 10 side. A signal (voltage signal) V corresponding to the difference between the magnitude of the flowing current IN is output. In other words, the inside of the hall sensor 21 is defined as “a current that flows from the external power supply 10 side toward the in-vehicle charger 40 side” as a positive current, the current that flows through the first power supply line L is defined as IL, and the second power supply line If the current flowing through N is IN, the magnitude | V | of the signal V is α · | IL + IN | (α is a positive constant). Accordingly, no leakage occurs, a current of magnitude A flows from the external power supply 10 side to the in-vehicle charger 40 side through the first power supply line L, and the second power supply line N from the in-vehicle charger 40 side to the external power supply. When a current of magnitude A flows to the 10 side, the magnitude of the signal V is “0” or substantially “0”. Similarly, no leakage occurs, a current of magnitude B flows from the in-vehicle charger 40 side to the external power source 10 side through the first power supply line L, and the second power supply line N is in-vehicle charged from the external power source 10 side. When a current of magnitude B flows to the side of the device 40, the magnitude of the signal V is “0” or substantially “0”. On the other hand, when a leakage occurs, either the magnitude of the current IN or the magnitude of the current IL is “0” or substantially “0”, and the magnitude of the other current is not “0”. The magnitude of the signal V is larger than a predetermined value.

  The relay 22 (relay RY1) includes a relay contact RY1-1 and a relay contact RY1-2. The relay contact RY1-1 is inserted in series with the first feed line L, and the relay contact RY1-2 is inserted in series with the second feed line N. The relay contact RY1-1 and the relay contact RY1-2 are simultaneously closed when the coil RY1 is energized, and are simultaneously opened when the coil RY1 is de-energized. The energization state of the coil RY1 is controlled based on a control signal from the control unit 26. In this specification, closing a contact such as a relay contact or a switch contact is also expressed as “contact is turned on”, and opening a contact is also expressed as “contact is turned off”.

  The resistor R1 and the switch S1 are connected in series with each other. The resistor R1 and the switch S1 are “on the line of the first power supply line L and closer to the external power supply 10 than the hall sensor 21” and “on the line of the second power supply line N and on the vehicle than the relay contact RY1-2. It is inserted in series in a connecting line connecting the “position on the charger 40 side”.

  The resistor R2 and the switch S2 are connected in series with each other. The resistor R2 and the switch S2 are “on the line of the second power supply line N and closer to the external power supply 10 than the hall sensor 21” and “on the line of the first power supply line L and on the vehicle than the relay contact RY1-1. It is inserted in series in a connecting line connecting the “position on the charger 40 side”.

  The resistor R3 and the switch S3 are connected in series with each other. The resistor R3 and the switch S3 are inserted in series on a connection line connecting the “position between the hall sensor 21 and the relay contact RY1-1 on the first power supply line L” and the “ground (FG)”. ing.

  The resistor R4 and the switch S4 are connected in series with each other. The resistor R4 and the switch S4 are inserted in series on the connection line connecting the “position between the hall sensor 21 and the relay contact RY1-1 on the first power supply line L” and the “ground (FG)”. ing. Therefore, “resistor R4 and switch S4” is connected in parallel with “resistor R3 and switch S3”.

  The switches S1 to S4 are semiconductor switches (relays) and are opened and closed based on a control signal from the control unit 26. When the switch S3 and the switch S4 are closed at the same time, the resistor R3 and the resistor R4 are selected so that a current exceeding the threshold value (for example, 15 mA) flows through the leakage breaker 11. As a result, when the switch S3 and the switch S4 are simultaneously closed, the earth leakage breaker 11 automatically opens the relay contacts RY0-1 and RY0-1, and interrupts the power supply circuit.

The amplifier 23 is connected to the hall sensor 21. The amplifier 23 amplifies the signal V output from the hall sensor 21. Therefore, the amplifier 23 and the hall sensor 21 have a magnitude of the current flowing through each of the pair of connection lines (the first power supply line L that is the first connection line and the second power supply line N that is the second connection line). A signal acquisition unit is configured to acquire a difference detection signal that is a signal corresponding to the difference.
The AD converter 24 converts the output signal of the amplifier 23 from analog to digital and outputs it.

  The filter unit 25 includes a band-pass filter BPF, a second low-pass filter LP2, and a third low-pass filter LP3. Each filter is a digital filter.

  The band pass filter BPF passes only a signal having a frequency equal to or higher than the “first frequency (for example, 10 Hz)” and equal to or lower than the “second frequency higher than the first frequency (for example, 500 Hz)”. That is, the band pass filter BPF extracts only the AC (alternating current) component included in the output signal V of the hall sensor 21. The reason why the band-pass filter BPF removes a signal having a frequency higher than the second frequency is to remove a surge.

  The second low-pass filter LP2 passes only signals having a frequency equal to or lower than the second frequency (for example, 500 Hz). That is, the second low-pass filter LP2 extracts only “AC (alternating current) component and DC (direct current) component” included in the output signal V of the hall sensor 21. The reason why the second low-pass filter LP2 removes a signal having a frequency higher than the second frequency is to remove a surge.

  The third low-pass filter LP3 passes only a signal having a frequency equal to or lower than “a third frequency lower than the second frequency (for example, 1 Hz)”. That is, the third low-pass filter LP3 extracts only a DC (direct current) component included in the output signal V of the hall sensor 21.

  The control unit 26 is a control circuit including a known microcomputer including a CPU, a ROM, a flash memory (F-ROM), a RAM, and the like. The control unit 26 inputs a signal from each filter of the filter unit 25 and a signal from the first low-pass filter 28. The control unit 26 sends a signal for opening and closing the switch S1 to the switch S4 to each of the switches, and sends a control signal to the gain setting device 29 and the alarm device 30.

The AC-DC insulated power supply 27 converts an AC voltage generated between the first power supply line L and the second power supply line N into a predetermined DC voltage, and converts the DC voltage into an “amplifier 23, AD converter 24. , To the filter unit 25, the control unit 26, the first low-pass filter 28 "and the like.
The gain setting unit 29 sets the gain of the amplifier 23 based on the control signal from the control unit 26.
The alarm device 30 includes an alarm / display device such as a buzzer and a plurality of LEDs. The buzzer of the alarm device 30 generates an alarm sound based on a signal from the control unit 26. The LED of the alarm device 30 is lit (or flashes) based on a signal from the control unit 26.

<In-vehicle charger>
A charger (on-vehicle charger) 40 mounted on a vehicle includes a boost converter 41, an insulated DC-DC converter 42, a charger ECU (Electric Control Unit) 43, and a diode D5.

  The step-up converter 41 is a well-known step-up PFC converter (power factor correction converter), and includes an X capacitor Cx, a first Y capacitor Cy1, a second Y capacitor Cy2, an input side resistor Rin, reactors L1, L2, diodes D1-D4, IGBT1, It includes IGBT2, leakage resistances RL1 and RL2, and electrolytic capacitor C1. The step-up converter 41 increases the “AC voltage between the first power supply line L and the second power supply line N” connected via the second connector Co2 to a DC voltage (difference between PVH + and PVH−). And convert. That is, the first connection line (first power supply line L) and the second connection line (second power supply line N) are connected to each of the pair of output terminal portions (a1, a2) of the external power source and the pair of inputs of the charger 40. It is a pair of connecting wires that connect each of the terminal portions (b1, b2).

More specifically, the first power supply line L is connected to one end of the reactor L1, and the second power supply line N is connected to one end of the reactor L2.
The X capacitor Cx is inserted between the first feeder line L and the second feeder line N on the input side of the reactors L1 and L2.
The first Y capacitor Cy1 is inserted between the first feeder L and the ground (FG) on the input side of the reactors L1 and L2.
The second Y capacitor Cy2 is inserted between the second feeder N and the ground (FG) on the input side of the reactors L1 and L2.
The input side resistance Rin is inserted between the first power supply line L and the second power supply line N on the input side with respect to the reactors L1 and L2.

The other end of the reactor L1 is connected to the anode of the diode D1. The cathode of the diode D1 is connected to the positive line (PVH +).
The other end of the reactor L2 is connected to the anode of the diode D2. The cathode of the diode D2 is connected to the positive line (PVH +).
The cathode of the diode D3 is connected to the anode of the diode D1. The anode of the diode D3 is connected to the negative electrode line (PVH−).
The cathode of the diode D4 is connected to the anode of the diode D2. The anode of the diode D4 is connected to the negative electrode line (PVH−).

IGBT means Insulated Gate Bipolar Transistor.
The IGBT 1 is connected in parallel with the diode D3.
The IGBT 2 is connected in parallel with the diode D4.
The leakage resistance RL1 exists in parallel with the diode D3.
The leakage resistance RL2 exists in parallel with the diode D4.

  The electrolytic capacitor C1 is inserted between the positive electrode line (PVH +) and the negative electrode line (PVH−). The anode and the anode of the electrolytic capacitor C1 are connected to the input terminal of the insulated DC-DC converter 42.

The insulated DC-DC converter 42 converts the voltage between the anode and the negative electrode of the electrolytic capacitor C1 into another voltage and outputs it from the output terminal. The first charging line M1 is connected to the positive output terminal of the insulated DC-DC converter 42, and the second charging line M2 is connected to the negative output terminal of the insulated DC-DC converter 42.
The diode D5 is inserted in series with the first charging line M1 so that its anode is connected to the positive output terminal of the insulated DC-DC converter 42.

  The charger ECU 43 is a control circuit including a microcomputer. The charger ECU 43 turns on and off the IGBT 1 and IGBT 2 at the boost control frequency fs and sends a control signal to the isolated DC-DC converter 42. Further, the charger ECU 43 exchanges various information with the control unit 26 through the communication line.

<Power storage device>
The power storage device 50 mounted on the vehicle includes an electrolytic capacitor C2, a discharge circuit 51 including a resistor and a switch, a relay 52, a storage battery 53, an inverter 54, a generator motor (motor / generator) 55, a PM-ECU 56, an MG-ECU 57, and a battery. ECU58 etc. are included.

The electrolytic capacitor C2 is inserted between the first charging line M1 and the second charging line M2.
The discharge circuit 51 is inserted between the first charging line M1 and the second charging line M2. The switch of the discharge circuit 51 is turned on / off according to a control signal from the battery ECU 58.

  The relay 52 includes a relay contact RY2-1 and a relay contact RY2-2. Relay contact RY2-1 is inserted in series with first charging line M1, and relay contact RY2-2 is inserted in series with second charging line M2. The relay contact RY2-1 and the relay contact RY2-2 are closed at the same time when the coil RY2 is energized, and are opened at the same time when the energization to the coil RY2 is interrupted. The energization state of the coil RY2 is controlled based on a control signal from the battery ECU 58.

  The storage battery 53 is a power storage element that can be charged and discharged (can be charged and discharged). Therefore, the storage battery 53 can be charged with electric power supplied from an external power source. The storage battery 53 is a lithium ion battery in this example. The storage battery 53 may be a secondary battery other than a lithium ion battery such as a nickel metal hydride battery and a lead storage battery, or may be another chargeable / dischargeable storage element. The anode of the storage battery 53 is connected to the first charging line M1 (output side of the relay RY2-1), and the cathode of the storage battery 53 is connected to the second charging line M2 (output side of the relay RY2-2).

  The inverter 54 is connected to the first charging line M1 and the second charging line M2. The inverter 54 converts the “DC voltage between the first charging line M1 and the second charging line M2” into a three-phase AC based on a control signal from the MG-ECU 57, and supplies this to the generator motor 55 to generate power. The electric motor 55 is driven. Further, the inverter 54 converts the three-phase alternating current generated by the generator motor 55 into a direct current voltage based on a control signal from the MG-ECU 57, and applies it between the first charging line M1 and the second charging line M2. It has become.

  The generator motor 55 functions as an electric motor and also functions as a generator. The output torque of the generator motor 55 is transmitted to the drive shaft of the hybrid vehicle. Further, the generator motor 55 is driven by an internal combustion engine (not shown).

The PM-ECU 56 is an ECU that executes drive control of the hybrid vehicle.
The MG-ECU 57 is an ECU that controls the inverter 54 and thereby controls the generator motor 55.
The battery ECU 58 is an ECU that monitors the state (SOC) of the storage battery 53 and controls the discharge circuit 51, the relay 52, and the like.
The PM-ECU 56, the MG-ECU 57, the battery ECU 58, and the charger ECU 43 are connected to each other via a communication line and exchange information.

(Operation)
Next, the operation of the charge monitoring device 20 configured as described above will be described. This operation is realized by the CPU of the control unit 26 executing the routines shown in the flowcharts of FIGS. 3, 5 to 7, and 14. In the following, when simply referred to as “CPU”, the CPU refers to the CPU of the control unit 26.

1. Self-check of the input unit of the charge monitoring device As shown in step 300 of FIG. 3, when the operator turns on the hand switch 12 and connects the first connector Co1 (that is, the connection unit 15 to the EV charging outdoor outlet 14). The CPU starts processing from step 310. Next, the CPU proceeds to step 320 to execute the following processing. At this stage, the relay 22 and the switches S1-S4 are all in an off state.

The CPU turns on (closes) the switch S3.
The CPU acquires (A / D converts) the current (leakage current) Ifs measured by the hall sensor 21 every predetermined sampling time Δt (for example, 4 ms) over a predetermined period (for example, 50 ms).
When the measurement is completed, the CPU calculates the frequency (and period T) of the current Ifs.
The CPU calculates the effective value Irms1 of the current Ifs according to the following equation (1) (see FIG. 4 for the effective value Irms of the arbitrary current I).

Irms1 = ((I1 ² +... + In ² ) · Δt) / T) ^1/2 (1)

The CPU stores the calculation result (Irms1) in the flash memory.
Thereafter, the CPU turns off (opens) the switch S3.

  Next, the CPU proceeds to step 330 to determine whether or not the current effective value Irms1 is larger than a first threshold value (for example, 5 mA). By the way, when the switch S3 is turned on, the effective value is “a first predetermined value larger than the first threshold value” in a circuit including the first power supply line L, the resistor R3, the switch S3, the ground line FG, and the second power supply line N. The resistor R3 is set in advance so that a current of (10 mA) "flows.

  Therefore, when the current effective value Irms1 is smaller than the first threshold value (5 mA), it can be determined that the ground line (FG line) is disconnected. Therefore, when the current effective value Irms1 is smaller than the first threshold value, the CPU makes a “No” determination at step 330 to proceed to step 340, and sends a signal to the alarm device 30 to indicate that the “ground line (FG line) is An alarm sound indicating that the wire is disconnected is generated from the buzzer, and the LED is turned on or blinked. Thereafter, the CPU proceeds to step 395 to end the process. That is, in this case, external charging is not started.

  On the other hand, when the current effective value Irms1 is larger than the first threshold value (5 mA), it can be determined that the ground line (FG line) is not disconnected. Therefore, in this case, the CPU makes a “Yes” determination at step 330 to proceed to step 350 to execute the following processing.

The CPU acquires (A / D converts) the current (leakage current) Ifs1 measured by the Hall sensor 21 every predetermined sampling time Δt (for example, 4 ms) over a predetermined period (for example, 50 ms).
When the measurement is completed, the CPU calculates the frequency (and period T) of the current Ifs1.
The CPU calculates an effective value Irms2 of the current Ifs1 according to the following equation (2).

Irms2 = ((I1 ² +... + In ² ) · Δt) / T) ^1/2 (2)

The CPU stores the calculation result (Irms2) in the flash memory as the offset value OFS1.

  Next, the CPU proceeds to step 360 to determine whether or not the contacts of the relay 22 (the relay contacts RY1-1 and the relay contacts RY1-2) are welded. More specifically, when the CPU proceeds to step 360, the CPU starts processing from step 500 in FIG. 5 and proceeds to step 510 to execute the following processing. At this time, the CPU sends a signal for opening the relay contact RY1-1 and the relay contact RY1-2.

The CPU turns on (closes) the switch S1.
The CPU acquires (A / D converts) the current (leakage current) IN measured by the Hall sensor 21 every predetermined sampling time Δt (for example, 4 ms) over a predetermined period (for example, 50 ms).
When the measurement is completed, the CPU calculates the frequency (and period T) of the current IN.
The CPU calculates an effective value Irms3 of the current IN according to the following equation (3).

Irms3 = ((I1 ² +... + In ² ) · Δt) / T) ^1/2 (3)

The CPU stores the calculation result (Irms3) in the flash memory.
Thereafter, the CPU turns off (opens) the switch S1.

  Next, the CPU proceeds to step 520 and determines whether or not the current effective value Irms3 is larger than a third threshold value (for example, 5 mA). By the way, when the switch S1 is turned on, if the current effective value Irms3 is larger than the third threshold value, it can be determined that the relay contacts RY1-2 are welded. Therefore, when the current effective value Irms3 is larger than the third threshold value, the CPU makes a “Yes” determination at step 520 to proceed to step 530 to determine that the relay contacts RY1-2 are welded. Thereafter, the CPU returns to step 360 in FIG.

  On the other hand, when the switch S1 is turned on and the current effective value Irms3 is equal to or smaller than the third threshold value, the CPU makes a “No” determination at step 520 to proceed to step 540 to execute the following processing. Also at this time, the CPU sends a signal for opening the relay contact RY1-1 and the relay contact RY1-2.

The CPU turns on (closes) the switch S2.
The CPU acquires (A / D converts) the current (leakage current) IL measured by the Hall sensor 21 every predetermined sampling time Δt (for example, 4 ms) over a predetermined period (for example, 50 ms).
When the measurement is completed, the CPU calculates the frequency (and period T) of the current IL.
The CPU calculates an effective value Irms4 of the current IL according to the following equation (3).

Irms4 = ((I1 ² +... + In ² ) · Δt) / T) ^1/2 (4)

The CPU stores the calculation result (Irms4) in the flash memory.
Thereafter, the CPU turns off (opens) the switch S2.

  Next, the CPU proceeds to step 550 to determine whether or not the current effective value Irms4 is larger than a fourth threshold value (for example, 5 mA). Incidentally, when the switch S2 is turned on, if the current effective value Irms4 is larger than the fourth threshold value, it can be determined that the relay contact RY1-1 is welded. Therefore, when the current effective value Irms4 is larger than the fourth threshold value, the CPU makes a “Yes” determination at step 550 to proceed to step 560 to determine that the relay contact RY1-1 is welded. Thereafter, the CPU returns to step 360 in FIG.

  On the other hand, when the switch S2 is turned on and the current effective value Irms4 is equal to or smaller than the fourth threshold value, the CPU makes a “No” determination at step 550 to proceed to step 570, where the relay contact RY1-1 and the relay It is determined that all the contacts RY1-2 are normal (not welded). Thereafter, the CPU returns to step 360 in FIG.

  When the CPU proceeds to either step 530 or step 560 of FIG. 5 (that is, when it is determined that either the relay contact RY1-1 or the relay contact RY1-2 is welded), FIG. 3 is determined as “Yes” in Step 360, the process proceeds to Step 370, a signal is sent to the alarm device 30, and “alarm sound indicating that the relay contact of the relay 22 is welded (failed)” is output from the buzzer. At the same time, the LED is turned on or blinked to indicate that. Thereafter, the CPU proceeds to step 395 to end the process. That is, in this case, external charging is not started.

  On the other hand, when the CPU proceeds to step 570 in FIG. 5 (that is, when it is determined that neither relay contact RY1-1 nor relay contact RY1-2 is welded), step 360 in FIG. In step 380, the relay 22 (relay RY1) is turned on, and the “LED of the alarm device 30 indicating that the relay 22 is turned on” is turned on. Thereafter, the CPU proceeds to step 610 in FIG. 6 (see numeral 1 in a circle in FIGS. 3 and 6).

2. The self-check of the entire charge monitoring device In step 610, the CPU determines whether the contact number of the relay 22 (relay contact RY1-1 and relay contact RY1-2) (the number of times the contact has been closed from the open) is the number of times of life (threshold number of times). For example, 30,000 times) or more. The CPU increments the relay open / close count counter each time an instruction to turn on the relay 22 is output, and performs the processing of step 610 using the open / close count counter.

  If the contact opening / closing frequency of the relay 22 is equal to or greater than the service life, the CPU makes a “Yes” determination at step 610 to proceed to step 620 to send a signal to the alarm device 30 to reach the service life of the relay 22. The LED is turned on or blinking to indicate that the relay 22 is turned off. Thereafter, the CPU proceeds to step 395 to end the process. That is, in this case, external charging is not started.

  On the other hand, if the contact opening / closing frequency of the relay 22 is less than the number of lifetimes, the CPU makes a “No” determination at step 610 to proceed to step 630 to execute the following processing.

The CPU acquires the current (leakage current) Ifs2 measured by the hall sensor 21 with the contact of the relay 22 closed, every predetermined sampling time Δt (for example, 4 ms) over a predetermined period (for example, 50 ms). (A / D conversion).
When the measurement is completed, the CPU calculates the frequency (and period T) of the current Ifs2. That is, the CPU acquires the frequency of the input power supply (external power supply).
The CPU calculates an effective value Irms5 of the current Ifs2 according to the following equation (5).

Irms5 = ((I1 ² +... + In ² ) · Δt) / T) ^1/2 (5)

The CPU stores the calculation result (Irms5) in the flash memory as the offset value OFS2.
The CPU sends a signal to the alarm device 30 and lights or blinks the LED so as to indicate that the measurement of the leakage current of the unit itself has been completed.

  Next, the CPU proceeds to step 640 and turns off the switch S1 after turning it on for a predetermined time (for example, 50 ms). In this period, the CPU acquires the current IN every predetermined sampling time Δt.

  Next, the CPU proceeds to step 650 and determines whether or not a leakage has been detected by determining whether or not the effective value of the current IN acquired in step 640 is greater than or equal to a predetermined value. Note that the effective value of the current IN is calculated according to an equation similar to the above equations (1) to (5). At this time, if the effective value of the current IN is less than a predetermined value (that is, if no leakage is detected), a failure has occurred in the first detection circuit system including the switch S1, the hall sensor 21, the amplifier 23, and the like. It can be judged.

  Therefore, if no leakage is detected at the time of determination in step 650, the CPU determines “No” in step 650, proceeds to step 660, sends a signal to the alarm device 30, and sends the first detection circuit system. The LED is turned on or blinked to indicate that has failed. Thereafter, the CPU turns off the relay 22, proceeds to step 395, and ends the process. That is, in this case, external charging is not started.

  On the other hand, if leakage is detected at the time of determination in step 650, the CPU determines “Yes” in step 650 and proceeds to step 670 to turn on the switch S2 for a predetermined time (for example, 50 ms). Turn off. In this period, the CPU acquires the current IL every predetermined sampling time Δt.

  Next, the CPU proceeds to step 680 and determines whether or not a leakage has been detected by determining whether or not the effective value of the current IL acquired in step 670 is greater than or equal to a predetermined value. Note that the effective value of the current IL is also calculated according to an equation similar to the above equations (1) to (5). At this time, if the effective value of the current IL is less than a predetermined value (that is, if no leakage is detected), a failure has occurred in the second detection circuit system including the switch S2, the Hall sensor 21, the amplifier 23, and the like. It can be judged.

  Therefore, if no leakage is detected at the time of determination in step 680, the CPU determines “No” in step 680 and proceeds to step 690 to send a signal to the alarm device 30 to send the second detection circuit system. The LED is turned on or blinked to indicate that has failed. Thereafter, the CPU turns off the relay 22, proceeds to step 395, and ends the process. That is, in this case, external charging is not started.

  On the other hand, if leakage is detected at the time of determination in step 680, the CPU determines “Yes” in step 680 and proceeds to step 692 to turn off the relay 22 and send a signal to the alarm device 30. The LED (normal display LED) is turned on or blinked to indicate that “the detection circuit system is normal”.

  Next, the CPU proceeds to step 694 and determines again whether or not the contacts of the relay 22 (the relay contact RY1-1 and the relay contact RY1-2) are welded. More specifically, when the CPU proceeds to step 694, the CPU executes the processing of the routine shown in FIG.

  When the CPU proceeds to either step 530 or step 560 of FIG. 5 (that is, when it is determined that either the relay contact RY1-1 or the relay contact RY1-2 is welded), FIG. 6 "Yes" is determined in step 694, and the process proceeds to step 696, where a signal is sent to the alarm device 30 and an "alarm sound indicating that the relay contact of the relay 22 is welded (failed)" is output from the buzzer. At the same time, the LED is turned on or blinked to indicate that. Thereafter, the CPU proceeds to step 395 to end the process. That is, in this case, external charging is not started.

  On the other hand, when the CPU proceeds to step 570 in FIG. 5 (that is, when it is determined that neither the relay contact RY1-1 nor the relay contact RY1-2 is welded), step 694 in FIG. The determination is “No” and the process proceeds to step 700 in FIG. 7 (see the numeral 2 in the circles in FIGS. 6 and 7).

3. Charge monitoring (leakage monitoring)
In step 700, the operator connects the second connector Co2 to the in-vehicle charger 40 by inserting the operation unit S shown in FIG. 2 into the inlet exposed on the side surface of the vehicle.

  When it is confirmed that the second connector Co2 is connected to the in-vehicle charger 40, the CPU turns on the relay 22 in step 705. Next, the CPU proceeds to step 710 and determines whether or not the number of times of opening / closing the contacts of the relay 22 (relay contacts RY1-1 and RY1-2) has reached the number of lifetimes or more. If the contact opening / closing frequency of the relay 22 is equal to or greater than the lifetime count, the CPU makes a “Yes” determination at step 710 to proceed to step 715 to send a signal to the alarm device 30 to reach the lifetime of the relay 22. The LED is turned on or blinked to indicate that. Thereafter, the CPU proceeds to step 750 to turn off the relay 22 and sends a signal to the alarm device 30 to turn on an LED indicating that the relay 22 is turned off.

  On the other hand, when the CPU executes the process of step 710, if the contact opening / closing frequency of the relay 22 is less than the lifetime, the CPU makes a “No” determination at step 710 and proceeds to step 720 to charge. A charge permission signal for permitting charging is sent to the device ECU 43. As a result, the charger ECU 43 sends a control signal to the boost converter 41, the insulated DC-DC converter 42, and the like. As a result, charging of the storage battery 53 by the external power supply starts. Further, the CPU sends a signal to the alarm device 30 to turn on an LED indicating that charging is in progress.

  When charging is started, the CPU executes the processing of “Step 725 and Step 730”, the processing of “Step 755 and Step 760”, and the processing of “Step 770 and Step 775” in a time-sharing manner in parallel. To do.

A. AC Leakage Detection In step 725, the CPU calculates the effective value Iac of the output value of the bandpass filter BPF of the filter unit 25 according to the following equation (6). The current value Iam (m is a natural number) in the equation (6) is a value that is output from the bandpass filter BPF every elapse of a predetermined time Δt. Note that the CPU may correct the effective value Iac using the offset value OFS2.

Iac = ((Ia1 ² +... + Ian ² ) · Δt) / T) ^1/2 (6)

  By the way, as shown in FIG. 8, when the human body comes into contact with the first feeder line L during execution of external charging, a closed circuit is formed as shown by the broken line LK1, and AC leakage (AC leakage) occurs. . In this case, the current IL is not “0”, and the current IN is “substantially 0”. Therefore, when AC leakage occurs, the effective value Iac of the output value of the bandpass filter BPF becomes larger than a predetermined AC leakage threshold (for example, 5 mA).

  Therefore, the CPU proceeds to step 730 in FIG. 7 and determines whether or not the effective value Iac is larger than the AC leakage threshold. At this time, if the effective value Iac is smaller than the AC leakage threshold, it can be determined that no AC leakage has occurred, so the CPU makes a “No” determination at step 730 to return to step 720.

  On the other hand, if the effective value Iac is larger than the AC leakage threshold value, it can be determined that AC leakage has occurred. Therefore, the CPU determines “Yes” in step 730 and proceeds to step 735 to notify the alarm device 30. A signal is sent to turn on the “LED indicating that AC leakage has occurred”. Thereafter, the CPU proceeds to step 745 to send a charge stop signal for stopping (complete) charging to the charger ECU 43. As a result, the charger ECU 43 stops the operation of the boost converter 41, the insulated DC-DC converter 42, and the like, so that the charging of the storage battery 53 by the external power supply is completed. Further, the CPU stores each data and error information (in this case, AC leakage is present) in the flash memory, and sends a signal to the alarm device 30 to indicate that external charging has been forcibly stopped (during charging). The LED indicating that there was a leakage) is turned on. Thereafter, the CPU proceeds to step 750, turns off the relay 22, sends a signal to the alarm device 30, and turns on an LED indicating that the relay 22 is turned off.

  Note that AC leakage (AC half-wave rectification leakage) also occurs when the closed circuit indicated by the broken line LK2 in FIG. 9 is formed. Furthermore, AC leakage (AC full-wave rectification leakage) also occurs when the closed circuit indicated by the broken line LK3 in FIG. 10 is formed.

B. DC Leakage Detection In step 755 of FIG. 7, the CPU calculates the effective value Idc of the output value of the third low-pass filter LP3 of the filter unit 25 according to the following equation (7). The current value Idm (m is a natural number) in the equation (7) is a value that is output from the third low-pass filter LP3 every elapse of the predetermined time Δt. The CPU may correct the effective value Idc using the offset value OFS2.

Idc = ((Id1 ² +... + Idn ² ) · Δt) / T) ^1/2 (7)

  By the way, as shown in FIG. 11, the first power supply line L is disconnected during charging at the point P, the resistance RL2 (insulation resistance at the middle point) is reduced, and a large amount of current is supplied to the electrolytic capacitor C1. If a human body contacts the anode side of the electrolytic capacitor C1 in a state where electric charges are accumulated, a closed circuit is formed as shown by a broken line LK4, and DC leakage (complete DC leakage) occurs. In this case, the current IL is “0”, and the magnitude of the direct current component of the current IN increases. Therefore, when DC leakage occurs, the effective value Idc of the output value of the third low-pass filter LP3 becomes larger than a predetermined DC leakage threshold (for example, 30 mA).

  Therefore, the CPU proceeds to step 760 in FIG. 7 and determines whether or not the effective value Idc is larger than the DC leakage threshold. At this time, if the effective value Idc is smaller than the DC leakage threshold, it can be determined that no DC leakage has occurred, so the CPU makes a “No” determination at step 760 to return to step 720.

  On the other hand, if the effective value Idc is larger than the DC leakage threshold value, it can be determined that a DC leakage has occurred. Therefore, the CPU makes a “Yes” determination at step 760 to proceed to step 765 to notify the alarm device 30. A signal is sent to turn on the “LED indicating that DC leakage has occurred”. Thereafter, the CPU proceeds to step 745 to perform the above-described processing. Thereby, the charging of the storage battery 53 by the external power supply is stopped. Further, the CPU proceeds to step 750, turns off the relay 22, sends a signal to the alarm device 30, and turns on an LED indicating that the relay 22 is turned off.

  Even when the first power supply line L is not disconnected at the point P, when a large amount of electric charge is accumulated in the electrolytic capacitor C1, if the human body comes into contact with the anode side of the electrolytic capacitor C1, IGBT1 and IGBT2 When either of these changes from OFF to ON, DC pulse leakage may occur due to the charge of the electrolytic capacitor C1 (see the broken line LK5 or the alternate long and short dash line LK6 in FIG. 12). Even in this case, the effective value Idc is larger than the DC leakage threshold.

C. Synthetic Leakage (DC + AC Leakage) Detection In step 770 of FIG. 7, the CPU calculates the effective value Idcac of the output value of the second low-pass filter LP2 of the filter unit 25 according to the following equation (8). The current value Idam (m is a natural number) in the equation (8) is a value output from the second low-pass filter LP2 every elapse of a predetermined time Δt.

Idcac = ((Ida1 ² +... + Idan ² ) · Δt) / T) ^1/2 (8)

  By the way, as shown in FIG. 13, when the resistance RL1 (midpoint insulation resistance) is lowered and a large amount of electric charge is accumulated in the electrolytic capacitor C1, a human body is placed on the anode side of the electrolytic capacitor C1. Contact with each other, a closed circuit is formed as indicated by a broken line LK7, and “DC + AC leakage (composite leakage in which DC leakage and AC leakage overlap) occurs. In this case, the current with respect to the magnitude of the current IN Therefore, when DC + AC leakage occurs, the effective value Idcac of the output value of the second low-pass filter LP2 becomes larger than a predetermined combined leakage threshold (for example, 30 mA).

  Therefore, the CPU proceeds to step 775 in FIG. 7 and determines whether or not the effective value Idcac is larger than the combined leakage threshold. At this time, if the effective value Idcac is smaller than the combined leakage threshold, it can be determined that the combined leakage has not occurred, so the CPU determines “No” in step 775 and returns to step 720.

  On the other hand, if the effective value Idcac is larger than the combined leakage threshold, it can be determined that a combined leakage has occurred, so the CPU determines “Yes” in step 775 and proceeds to step 780 to notify the alarm device 30. A signal is sent to light the “LED indicating that a combined leakage (AC + DC leakage) has occurred”. Thereafter, the CPU proceeds to step 745 to perform the above-described processing. Thereby, the charging of the storage battery 53 by the external power supply is stopped. Further, the CPU proceeds to step 750, turns off the relay 22, sends a signal to the alarm device 30, and turns on an LED indicating that the relay 22 is turned off.

  When the CPU completes the process of step 750, the CPU proceeds to step 1410 of FIG. 14 (see numeral 3 in a circle of FIGS. 7 and 14). In step 1410, the CPU determines again whether or not the contacts (relay contacts RY1-1 and RY1-2) of the relay 22 are welded. More specifically, when proceeding to step 1410, the CPU executes the processing of the routine of FIG.

  When the CPU proceeds to step 570 in FIG. 5 (that is, when it is determined that neither relay contact RY1-1 nor relay contact RY1-2 is welded), in step 1410 in FIG. It determines with "No", progresses directly to step 395, and complete | finishes a process.

  In contrast, when the CPU proceeds to either step 530 or step 560 in FIG. 5 (that is, either relay contact RY1-1 or relay contact RY1-2 is determined to be welded). 14), it is determined as “Yes” in Step 1410 of FIG. 14 and proceeds to Step 1420. By executing the same processing as the processing of “Step 320 and Step 330” in FIG. 3, the ground line (FG line) is It is determined whether or not there is a break.

  At this time, if the CPU determines that the ground line (FG line) is disconnected, it determines “Yes” in step 1420 and proceeds to step 1430, where “the ground line (FG line) is disconnected”. Information to that effect is stored in the flash memory. Further, the CPU sends a signal to the alarm device 30 to generate an “alarm sound indicating that the relay 22 is welded and the ground line (FG line) is disconnected” from the buzzer, and the LED is lit or blinked. Let Thereafter, the CPU proceeds to step 395 to end the process.

  On the other hand, if the CPU determines that the ground line (FG line) is not disconnected, it determines “No” in step 1420 and proceeds to step 1440, where “relay 22 is welded and ground line (FG line). ) Is stored in the flash memory.

  Next, the CPU proceeds to step 1450 to turn on both the switch S3 and the switch S4. Thereby, since the electric current more than the threshold value (for example, 15 mA) mentioned above flows into the earth leakage breaker 11, the earth leakage breaker 11 is turned off and the power supply circuit from the external power source is interrupted. Thereafter, the CPU proceeds to step 395 to end the process. Note that the CPU can proceed to step 750 in FIG. 7 even when the charge termination request is generated by the battery ECU 58 or the like.

As described above, the charge monitoring device 20 is
Charging the power storage device (53) mounted on the vehicle by using AC power (AC200V) supplied from an external power source through a circuit breaker (11) that cuts off the path when a current exceeding a predetermined threshold flows. In carrying out, it inserts between the said circuit breaker (11) and the charger (40) mounted in the said vehicle and connected to the said electrical storage apparatus.

The charge monitoring device 20
A feeder line (first feeder line L and second feeder line N) connecting the circuit breaker (11) and the charger (40);
A relay device (22) including relay contacts (RY1-1, RY1-2) inserted in the feeder line;
A welding detector (resistor R1, switch S1, "steps 510 to 530" in FIG. 5), resistor R2, switch S2, and "steps 540 to 540 in FIG. 5" for detecting the welding of the relay contacts (RY1-1, RY1-2). Step 560 ").
A circuit configured so that a current equal to or greater than the threshold value flows through the circuit breaker (11) when welding of the relay contact is detected (the resistor R3 and the resistor R4 are connected between the first feeder L and the ground wire). A switch device (switch S3, switch S4, see step 1410, step 1420 and step 1450 in FIG. 14) that is closed to establish a circuit.
Is provided.

  Therefore, when the welding of the relay contacts (RY1-1, RY1-2) of the relay device 22 is detected, the switch device (switch S3, switch S4) is closed, so that a current exceeding the threshold value is supplied to the circuit breaker (11). Since it flows, the circuit breaker 11 operates and the power feeding path is opened. Therefore, the supply of power from the external power source to the charger 40 is stopped. As a result, even if the relay contacts (RY1-1, RY1-2) are welded, it is possible to avoid the leakage of electricity.

Furthermore, the charge monitoring device 20
When charging the power storage device (53) mounted on the vehicle by using AC power from an external power source supplied between the pair of output terminal portions (see points a1 and a2 in FIG. 1), The pair of output terminal portions (points a1 and a2 in FIG. 1) and a pair of input terminal portions (points b1 and b2 in FIG. 1) of the charger (40) mounted on the vehicle and connected to the power storage device. A charge monitoring device inserted between
A pair of connection lines (firsts) connecting the pair of output terminal portions (points a1, a2 in FIG. 1) of the external power source and the pair of input terminal portions of the charger (points b1, b2 in FIG. 1). 1 feeder line L, second feeder line N),
A signal acquisition unit (a hall sensor 21 and an operational amplifier) that acquires a difference detection signal that is a signal corresponding to a difference in magnitude of a current flowing through each of the pair of connection lines (first feeding line L, second feeding line N). 23).
It is determined whether or not a DC leakage has occurred based on a value corresponding to the magnitude of the first signal obtained by performing low-pass filter processing on the difference detection signal (third low-pass filter LPF3, FIG. 7). Step 755 and step 760 of FIG. 5), and whether or not AC leakage has occurred based on a value corresponding to the magnitude of the second signal obtained by performing band-pass filter processing on the difference detection signal. (Refer to bandpass filter BPF, see step 725 and step 730 in FIG. 7)
Is provided.

  Therefore, the charge monitoring device 20 can distinguish whether the leakage is a direct current leakage or an alternating current leakage with a simple circuit configuration without using a zero-phase current transformer or the like. Furthermore, a difference detection signal that is a signal corresponding to the difference in the magnitude of the current flowing through each of the pair of connection lines (the first power supply line L and the second power supply line N) can be acquired by one Hall sensor 21. .

  The present invention is not limited to the above embodiment, and various modifications can be employed within the scope of the present invention. For example, only one of the processing of “Step 725 and Step 730”, the processing of “Step 755 and Step 760”, and the processing of “Step 770 and Step 775” in FIG. 7 may be performed. . Boost converter 41 may be another type of converter. In addition, the charge monitoring device 20 can be applied to an electric vehicle that does not include an internal combustion engine. Further, instead of the Hall sensor 21, a difference detection signal is obtained using a first current sensor that measures the current flowing through the first feeder line L and a second current sensor that measures the current flowing through the second feeder line N. May be.

  DESCRIPTION OF SYMBOLS 10 ... External power supply, 11 ... Leakage breaker, 20 ... Charge monitoring device, 21 ... Hall sensor, 22 ... Relay (relay device), 23 ... Amplifier, 25 ... Filter part, 26 ... Control unit, 30 ... Alarm device, 40 ... Charger, 50 ... Power storage device, 53 ... Storage battery.

Claims (3)

When charging a power storage device mounted on a vehicle by using AC power supplied from an external power source through a circuit breaker that interrupts the path when a current exceeding a predetermined threshold flows through the path, the circuit breaker And a charging monitoring device inserted between the battery charger mounted on the vehicle and connected to the power storage device,
A power supply line connecting the circuit breaker and the charger;
A relay device including a relay contact inserted in the feeder line;
A welding detector for detecting welding of the relay contact;
A switch device that is closed to establish a circuit configured to allow a current greater than or equal to the threshold value to flow in the path of the circuit breaker when welding of the relay contact is detected;
A charge monitoring device comprising: The charge monitoring device according to claim 1,
The power supply line is a pair of connection lines connected to each of the pair of output terminal portions of the circuit breaker and each of the pair of input terminal portions of the charger,
The charge monitoring device further includes:
A signal acquisition unit that acquires a difference detection signal that is a signal corresponding to a difference in magnitude of a current flowing through each of the pair of connection lines;
It is determined whether or not a DC leakage has occurred based on a value corresponding to the magnitude of the first signal obtained by performing low-pass filter processing on the difference detection signal, and for the difference detection signal A leakage monitoring unit that determines whether or not AC leakage has occurred based on a value corresponding to the magnitude of the second signal obtained by performing the band-pass filter processing;
A charge monitoring device comprising: In charging the power storage device mounted on the vehicle by using AC power from an external power supply supplied between the pair of output terminal units, the pair of output terminal units, the vehicle mounted on the vehicle, and the A charge monitoring device inserted between a pair of input terminal portions of a charger connected to a power storage device,
A pair of connection lines connecting each of the pair of output terminal portions of the external power source and each of the pair of input terminal portions of the charger;
A signal acquisition unit that acquires a difference detection signal that is a signal corresponding to a difference in magnitude of a current flowing through each of the pair of connection lines;
It is determined whether or not a DC leakage has occurred based on a value corresponding to the magnitude of the first signal obtained by performing low-pass filter processing on the difference detection signal, and for the difference detection signal A leakage monitoring unit that determines whether or not AC leakage has occurred based on a value corresponding to the magnitude of the second signal obtained by performing the band-pass filter processing;
A charge monitoring device comprising:

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