WO2023188140A1 - Electric vehicle control device - Google Patents

Abstract

This electric vehicle control device is provided with: a power conversion device (10) that is mounted in an electric vehicle, receives a supply of power from a power source (12), and converts direct-current power into alternating-current power; a first switch (30) that switches between passing and blocking electric current flowing between the power source (12) and the power conversion device (10); a capacitor (20) that is connected to the direct-current side of the power conversion device (10); a first discharge circuit that is connected to both ends of the capacitor (20) and comprises a discharge resistor (80) and a discharge contactor (90); and a second discharge circuit that is connected to both ends of the capacitor (20) and that comprises a first resistor (70) and a second switch (31) connected in series between the first switch (30) and the capacitor (20).

Description

electric car control device

The present disclosure relates to an electric vehicle control device that is supplied with power from an external power source and discharges power to the outside.

Electric cars convert DC power into AC power using an inverter and supply it to the auxiliary power supply. Before operating the inverter, it is necessary to charge the filter capacitor, and after the inverter stops operating, it is necessary to discharge the charge accumulated in the filter capacitor. Patent Document 1 discloses that a discharge circuit for discharging a filter capacitor is provided.

Japanese Patent Application Publication No. 2010-41806

Patent Document 1 discloses that a discharge current from a filter capacitor via an initial charging circuit is detected during an inverter stop operation, and a failure detection unit detects that a discharge current detected by a current detection sensor during a stop operation exceeds a predetermined value. It is disclosed that, in this case, it is determined that there is a short-circuit failure in the backflow prevention element of the initial charging circuit. However, in Patent Document 1, there is a problem in that if there is an abnormality in the discharge circuit due to poor contact between parts constituting the discharge circuit, the charge in the filter capacitor cannot be discharged.

The present disclosure has been made in order to solve the above-mentioned problems, and it is an object of the present disclosure to provide an electric vehicle control device that can reliably discharge the charge of a filter capacitor when there is an abnormality in the discharge circuit. With the goal.

In order to achieve the above object, an electric vehicle control device according to the present disclosure includes a power conversion device that is installed in an electric vehicle, receives power from a power source, and converts DC power into AC power, and a power source and a power conversion device. Consisting of a first switch that switches on and off the current flowing between the device, a capacitor connected to the DC side of the power conversion device, a discharge resistor and a discharge contactor connected to both ends of the capacitor. a second discharge circuit connected to both ends of the capacitor, a second switch, and a first resistor connected in series between the first switch and the capacitor; Equipped with.

An electric vehicle control device according to the present disclosure includes a power conversion device that is installed in an electric vehicle, receives power from a power source, and converts DC power into AC power; a first switch for switching on and off; a capacitor connected to the DC side of the power conversion device; and a first discharge circuit connected to both ends of the capacitor and consisting of a discharge resistor and a discharge contactor. , a second discharge circuit connected across the capacitor and consisting of a second switch and a first resistor connected in series between the first switch and the capacitor. Charge can be reliably discharged.

1 is a block diagram showing a configuration example of an electric vehicle control device according to a first embodiment; FIG. FIG. 3 is a diagram showing an example of the operation of the electric vehicle control device according to the first embodiment. FIG. 2 is a block diagram showing a configuration example of an electric vehicle control device according to a second embodiment. 1 is a diagram illustrating a general configuration example of hardware that implements an electric vehicle control device according to an embodiment.

Embodiments of an electric vehicle control device according to the present disclosure will be described below with reference to the drawings.
In this specification and the drawings, components having substantially the same functions are denoted by the same reference numerals and redundant explanation will be omitted. Further, in the drawings, the diagrams showing the configurations of circuits and devices are only diagrams showing the schematic configuration. In the following description, connected means electrically connected.

Embodiment 1.
FIG. 1 is a block diagram showing a configuration example of an electric vehicle control device according to Embodiment 1 of the present disclosure. In FIG. 1, the electric vehicle control device includes a power converter 10, a filter capacitor 20, a voltage detector 21, a first switch 30, a second switch 31, a circuit breaker 40, a filter reactor 50, a backflow prevention thyristor 60, a 1 resistor 70, discharge resistors 80, 81, and discharge contactor 90.

The power conversion device 10 converts the power supplied from the power supply 12 into DC power or AC power, and supplies the converted power to a load (not shown). Here, the load is, for example, an auxiliary power supply device. The power conversion device 10 is, for example, a two-level three-phase inverter circuit or a three-level three-phase inverter circuit.

The current collector 11 acquires DC power from a substation (not shown), which is an external circuit, via the power supply 12 and supplies the power to the power conversion device 100. The current collector 11 is, for example, a pantograph that receives power from an overhead wire, or a current collector shoe that receives power from a third rail.

The power supply 12 is connected to a substation, and DC power is supplied from the substation. The power source 12 is, for example, an overhead wire or a third rail.

The filter capacitor 20 is provided in parallel with the power converter 10. One end of filter capacitor 20 is connected to power converter 10 , voltage detector 21 , backflow prevention thyristor 60 , first resistor 70 , and discharge resistors 80 and 81 . The other end of filter capacitor 20 is grounded. Filter capacitor 20 is provided on the DC side of power converter 10 .

The voltage detector 21 is provided in parallel with the power converter 10. One end of the voltage detector 21 is connected to the power conversion device 10, the filter capacitor 20, the backflow prevention thyristor 60, the first resistor 70, and the discharge resistors 80 and 81. The other end of the voltage detector 21 is grounded.

The first switch 30 is electrically provided in series between the current collector 11 and the power converter 10. One end of the first switch 30 is connected to the current collector 11 . The other end of the first switch 30 is connected to a circuit breaker 40. The first switch 30 is opened when it is necessary to stop supplying power to the electric vehicle. By opening the first switch 30, the current collector 11 and the power converter 10 are electrically cut off, and the supply of power from the current collector 11 to the power converter 10 is stopped. When it is necessary to supply power to the electric vehicle, the first switch 30 is turned on. By turning on the first switch 30, the current collector 11 and the power converter 100 are electrically connected, and power is supplied from the power source 12 to the power converter 10.

The circuit breaker 40 is electrically provided in series between the current collector 11 and the power converter 10. One end of the circuit breaker 40 is connected to the first switch 30. The other end of the circuit breaker 40 is connected to a filter reactor 50. The circuit breaker 40 is opened when it is necessary to stop supplying power to the electric vehicle. By opening the circuit breaker 40, the current collector 11 and the power converter 10 are electrically interrupted, and the supply of power from the current collector 11 to the power converter 10 is stopped. When it is necessary to supply power to the electric vehicle, the circuit breaker 40 is turned on. By turning on the circuit breaker 40, the current collector 11 and the power converter 10 are electrically connected, and power is supplied from the power source 12 to the power converter 100.

The filter reactor 50 is electrically provided in series between the current collector 11 and the power converter 10. One end of the filter reactor 50 is connected to the circuit breaker 40. The other end of filter reactor 50 is connected to second switch 31 , backflow prevention thyristor 60 and first resistor 70 . Filter reactor 50 smoothes the current flowing from power supply 12 to power converter 10 . Filter reactor 50 and filter capacitor 20 constitute an LC filter circuit, and are provided to suppress harmonics generated when power conversion device 10 performs power conversion from flowing to power supply 12 .

The backflow prevention thyristor 60 is electrically provided in series between the current collector 11 and the power converter 10. One end of the backflow prevention thyristor 60 is connected to the second switch 31, filter reactor 50, and first resistor 70. The other end of the backflow prevention thyristor 60 is connected to the power converter 10, filter capacitor 20, voltage detector 21, first resistor 70, and discharge resistors 80 and 81. The anti-backflow thyristor 60 is connected in parallel with the first resistor 70 . Anti-backflow thyristor 60 prevents current from flowing from filter capacitor 20 to power supply 12 .

The first resistor 70 is provided electrically in series between the current collector 11 and the power converter 10. One end of the first resistor 70 is connected to the second switch 31, filter reactor 50, and backflow prevention thyristor 60. The other end of the first resistor 70 is connected to the power converter 10 , filter capacitor 20 , voltage detector 21 , backflow prevention thyristor 60 , and discharge resistors 80 and 81 . The first resistor 70 is connected in parallel with the anti-backflow thyristor 60 . The first resistor 70 is a charging resistor for preventing rush current when charging the filter capacitor 20. Further, the first resistor 70 serves as a discharge resistance when the filter capacitor 20 is abnormally discharged. Details will be described later. A first resistor 70 is connected in series between the first switch 30 and the filter capacitor 20 .

The discharge resistors 80 and 81 are provided in parallel with the power converter 10. Discharge resistors 80 and 81 are connected in parallel. One ends of the discharge resistors 80 and 81 are connected to the power conversion device 10 , the filter capacitor 20 , the voltage detector 21 , the backflow prevention thyristor 60 , and the first resistor 70 . The other ends of the discharge resistors 80 and 81 are connected to a discharge contactor 90. The electric vehicle control device is equipped with multiple discharge resistors, so even if one of the discharge resistors has an abnormality due to poor contact, the other discharge resistor with no poor contact will be energized. This enables discharge. Three or more discharge resistors may be provided.

The discharge contactor 90 is provided in parallel with the power converter 10. One end of the discharge contactor 90 is connected to the discharge resistors 80 and 81. The other end of the discharge contactor 90 is grounded. Discharge resistors 80 and 81 are connected in series with discharge contactor 90. Discharge resistors 80, 81 and discharge contactor 90 are connected to both ends of the capacitor and constitute a first discharge circuit.

The second switch 31 is provided in parallel with the power conversion device 10. One end of the second switch 31 is connected to the filter reactor 50, the backflow prevention thyristor 60, and the first resistor 70. The other end of the second switch 31 is grounded. The second switch 31 is connected in series with the first resistor 70. The second switch 31 and the first resistor 70 constitute a second discharge circuit. During normal operation, the second switch 31 is open and does not conduct electricity. The second switch 31 is turned on when the filter capacitor 20 is abnormally discharged. By turning on the second switch 31, the electric charge stored in the filter capacitor 20 is discharged. Details will be described later.

The operation of the electric vehicle control device according to Embodiment 1 of the present disclosure will be described. A charging operation for charging the filter capacitor 20 will be described. In order to operate the power conversion device 10, the filter capacitor 20 is charged. In order to charge the filter capacitor 20, it is necessary to supply power from the power source 12, and the first switch 30 and the circuit breaker 40 are turned on (closed). By turning off the backflow prevention thyristor 60 and energizing the first resistor 70 without energizing the backflow prevention thyristor 60, the filter capacitor 20 can be charged without an inrush current flowing. After the voltage detector 21 detects a voltage equal to or higher than a predetermined value, the backflow prevention thyristor 60 is turned on and the backflow prevention thyristor 60 is energized to short-circuit and charge the filter capacitor 20. The first switch 30 and the circuit breaker 40 are closed while the filter capacitor 20 is being charged.

Next, it is a diagram illustrating an operation in which filter capacitor 20 of the electric vehicle control device according to the first embodiment is discharged. The control unit (not shown) of the electric vehicle control device opens the circuit breaker 40 in order to start discharging the filter capacitor 20 (S11). By opening the circuit breaker 40, the supply of power from the power source 12 is stopped. Next, the operation of the power conversion device 10 is stopped (S12). The discharge contactor 90 is turned on (S13), and the charge accumulated in the filter capacitor is discharged. After a predetermined period has elapsed, it is checked whether the voltage value of the voltage detector 21 is below a predetermined value (predetermined value) (S14). If the voltage value of the voltage detector 21 is below the predetermined value after the predetermined period has elapsed (S14: Y), there is no abnormality in the first discharge circuit, and the discharge is performed normally. After confirming that the voltage value of the voltage detector 21 is 0V (S16), the discharging operation is completed. If the voltage value of the voltage detector 21 does not become less than the predetermined value after a predetermined period has elapsed after the discharge contactor 90 is turned on (S14:N), the state is in a non-discharge state. Therefore, it is assumed that there is an abnormality in the first discharge circuit. In other words, an abnormality in the first discharge circuit is detected. Therefore, in order to ensure discharge, the first switch 30 is opened and the second switch 31 is turned on (S15). By turning on the second switch 31, a second discharge circuit is formed by the first resistor 70 and the second switch 31. The filter capacitor 20 is discharged by the second discharge circuit, and after confirming that the voltage value of the voltage detector 21 is 0V (S16), the discharge operation is completed.

The electric vehicle control device according to the first embodiment includes a plurality of discharging resistors in the first discharging circuit, so that even if one of the discharging resistors does not conduct electricity due to a poor contact, a poor contact can be avoided. By energizing the other discharging resistor, discharging becomes possible. Further, even if there is no abnormality in the discharge resistor, if there is an abnormality in the discharge contactor 90, normal discharge cannot be performed. Even in that case, the electric vehicle control device detects an abnormality in the first discharge circuit by monitoring the voltage value of the voltage detector 21, and forms a second discharge circuit. By performing the discharge by the second discharge circuit, the charge in the filter capacitor 20 can be reliably discharged.

In the voltage detector 21, after a predetermined period has elapsed, it is confirmed whether the voltage value is below a predetermined value. Here, the predetermined period is, for example, 5 minutes; The predetermined value is, for example, 50V, but is not limited to this. The predetermined period and predetermined value may be set as appropriate.

The electric vehicle control device according to the first embodiment operates the first switch 30 and the second switch 31 in conjunction with each other when forming the second discharge circuit. Since the first switch 30 and the second switch 31 are interlocked, when the first switch 30 is opened, no current flows to the power supply 12 side, and when the second switch 31 is turned on, no current flows to the power supply 12 side. , it becomes possible to reliably flow current to the ground side. Further, since the second discharge circuit conducts electricity through the first resistor 70, a voltage drop occurs, thereby preventing the impedance from becoming low during discharge. Low impedance is a case where the high voltage side and the low voltage side of the filter capacitor 20 are short-circuited. If the impedance is lowered during discharge, a large current will flow and there is a risk of electric shock. However, the electric vehicle control device according to the first embodiment can prevent the impedance from becoming low during discharge.

In the electric vehicle control device according to the first embodiment, the backflow prevention thyristor 60 may have a contactor (not shown) connected in series. In this case, the contactor may be closed when the filter capacitor 20 is charged and opened when the filter capacitor 20 is discharged. By connecting a contactor in series with the backflow prevention thyristor 60, a second discharge circuit is formed, and when the filter capacitor 20 is discharged, the contactor is opened, so that the discharge current flows through the backflow prevention thyristor 60. Since the first resistor 70 side is not energized and the first resistor 70 side is energized, even if the backflow prevention thyristor 60 is short-circuited, the first resistor 70 side is reliably energized, resulting in low impedance during discharge. can be prevented.

The electric vehicle control device according to the first embodiment includes a power conversion device that is mounted on an electric vehicle, receives power from a power source, and converts DC power into AC power, and a power converter that receives power from a power source and that flows between the power source and the power conversion device. A first switch that switches on and off the current, a capacitor connected to the DC side of the power converter, and a first discharge that is connected to both ends of the capacitor and includes a discharge resistor and a discharge contactor. a second discharge circuit connected across the capacitor and consisting of a second switch and a first resistor connected in series between the first switch and the capacitor; The charge in the capacitor can be reliably discharged.

The electric vehicle control device according to the first embodiment includes a voltage detector connected in parallel with the capacitor, and detects an abnormality in the first discharge circuit by monitoring the voltage of the voltage detector. , the first discharge circuit detects that the charge on the filter capacitor cannot be discharged.

In the electric vehicle control device according to the first embodiment, after an abnormality in the first discharge circuit is detected, the opening of the first switch and the closing of the second switch are controlled in conjunction with each other, thereby controlling the discharge path. It becomes possible to change the discharge circuit to the second discharge circuit.

In the electric vehicle control device according to the first embodiment, the discharging resistor has a plurality of resistors connected in parallel, so that even if one resistor is defective, the electric charge of the filter capacitor can be reliably charged. Can be discharged.

Embodiment 2.
In the first embodiment, the first resistor 70 and the second switch 31 form the second discharge circuit. In the second embodiment, a second discharge circuit including a filter reactor 50 is formed.

FIG. 3 is a block diagram showing a configuration example of an electric vehicle control device according to Embodiment 2 of the present disclosure. In FIG. 3, the difference from the first embodiment is that a contactor 100 is provided.

One end of the contactor 100 is connected to the circuit breaker 40 and the filter reactor 50. The other end of contactor 100 is connected to second switch 31 . Contactor 100 is opened when filter capacitor 20 is charged. Therefore, the control for charging the filter capacitor 20 is the same as in the first embodiment.

The contactor 100 is turned on when the filter capacitor 20 is discharged. When the filter capacitor 20 is discharged, the contactor 100 is turned on at the same time as the second switch 31 is turned on in S15 of FIG. When the contactor 100 is turned on, the second discharge circuit is configured by the first resistor 70, the filter reactor 50, the contactor 100, and the second switch 31. In the second discharge circuit, by providing the filter reactor 50, when the charge of the filter capacitor 20 is discharged, the amount of current at the start of discharge can be suppressed by the time constant of the filter reactor 50, and inrush current can be suppressed. becomes possible.

The electric vehicle control device according to the second embodiment includes a filter reactor connected in series between the second switch and the first resistor, so that when discharging the charge of the filter capacitor, the electric vehicle control device starts discharging. The amount of current can be suppressed.

A control unit (not shown) of the electric vehicle control device includes at least a processor, a memory, a receiver, and a transmitter, and the operation of each device can be realized by software. FIG. 4 is a diagram illustrating a general configuration example of hardware that implements the control unit of the electric vehicle control device according to the embodiment. The device shown in FIG. 4 includes a processor 1001, a memory 1002, a receiver 1003, and a transmitter 1004, and the processor 1001 uses received data to perform calculations and control using software. The memory 1002 stores received data or data necessary for the processor 1001 to perform calculations and control, and also stores software. The receiver 1003 is an interface that receives signals or information input to the electric vehicle control device. The transmitter 1004 is an interface for transmitting signals or information output from the electric vehicle control device. Note that a plurality of each of the processor 1001, memory 1002, receiver 1003, and transmitter 1004 may be provided.

In Embodiments 1 and 2, it has been explained that when the charge of the filter capacitor 20 is discharged, the first discharge circuit and the second discharge circuit are switched and the charge is discharged using one of the discharge circuits. , both discharge circuits may be used simultaneously. When using both discharge circuits, even if one discharge circuit cannot discharge due to poor contact or the like, it is possible to continue discharging with the other discharge circuit without switching. Further, if there is a discharge circuit that cannot discharge, the contactor or the second switch is opened so that the discharge circuit that cannot discharge is not energized. Specifically, when discharge cannot be performed by the first discharge circuit, the discharge contactor 90 is opened, and when discharge cannot be performed by the second discharge circuit, the second switch 31 is opened.

In the first and second embodiments, the means for detecting that the first discharge circuit is abnormal may be automatic or manual. Even if the voltage value of the voltage detector 21 is output to an external device and the external device checks whether the voltage value of the voltage detector 21 is below the predetermined value after a predetermined period has elapsed. good.

In Embodiments 1 and 2, the control to turn on and open the discharge contactor 90 of the first discharge circuit and the second switch 31 of the second discharge circuit may be performed automatically, You can also do it manually.

10 power conversion device, 11 current collector, 12 power supply, 20 filter capacitor, 21 voltage detector, 30 first switch, 31 second switch, 40 circuit breaker, 50 filter reactor, 60 backflow prevention thyristor, 70 first resistor, 80, 81 discharge resistor, 90 discharge contactor, 100 contactor, 1001 processor, 1002 memory, 1003 receiver, 1004 transmitter 10.

Claims (5)

A power conversion device that is installed in an electric vehicle, receives power from a power source, and converts DC power to AC power;
a first switch that switches on and off the current flowing between the power source and the power conversion device;
a capacitor connected to the DC side of the power converter;
a first discharging circuit connected to both ends of the capacitor and comprising a discharging resistor and a discharging contactor;
a second discharge circuit configured from a first resistor and a second switch connected to both ends of the capacitor and connected in series between the first switch and the capacitor;
Electric vehicle control device equipped with comprising a voltage detector connected in parallel with the capacitor,
An abnormality in the first discharge circuit is detected by monitoring the voltage of the voltage detector.
The electric vehicle control device according to claim 1. After an abnormality in the first discharge circuit is detected, opening of the first switch and closing of the second switch are controlled in conjunction.
The electric vehicle control device according to claim 2. The discharge resistor includes a plurality of resistors connected in parallel.
The electric vehicle control device according to any one of claims 1 to 3. The second discharge circuit includes a filter reactor connected in series between the second switch and the first resistor.
The electric vehicle control device according to any one of claims 1 to 4.

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