JP2013055844A - Power supply device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a short-circuit failure of a charging resistor short circuit switch, CHS, while a power supply device for a vehicle is operating or the vehicle is being operated.SOLUTION: A power supply device for a vehicle comprises: a resistor; a CHS unit 10 that includes a short-circuiting switch of a self-arc-extinguishing type semiconductor for short-circuiting the resistor; an inverter 8 for converting DC power supplied from wiring via the CHS unit to AC power; a filter capacitor connected in parallel to a DC side terminal of the inverter; a voltage detector 4 for detecting a DC side input voltage of the inverter; and a controller 20 for controlling the short-circuiting switch. In the power supply device for the vehicle, the controller 20 turns off the short-circuiting switch in a conduction state for a predetermined time period, measures a voltage of the filter capacitor by the voltage detector 4 before turning off the short-circuiting switch and during turning off the short-circuiting switch and, in a case where a voltage difference between on/off states thereof is less than a predetermined value, determines that the short-circuiting switch has a short-circuit failure.

Description

  The present invention relates to a vehicle power supply device used in a train or the like.

  In general, a vehicle power supply device mounted on a railway vehicle receives power from an overhead line and supplies power to a train lighting, an air conditioner, and the like. This vehicle power supply device is a device that generates alternating current or direct current by switching with a semiconductor device switching device such as IGBT, and includes, for example, an inverter that converts direct current voltage into alternating current voltage.

  In such a vehicle power supply device, when charge is accumulated in the input filter capacitor of the inverter at the start of operation, in order to suppress inrush current, the overhead voltage is applied to the filter capacitor via the charging resistor for a certain period of time. The circuit configuration is such that is supplied. After the charge is accumulated, a switch for short-circuiting the charging resistor is turned on. The charging resistor short-circuit switch (CHS) generally uses a semiconductor element such as GTO or IGBT.

  Since the CHS is normally in a conductive state during operation of the vehicle power supply device, a short circuit failure of the CHS can generally be detected only when the vehicle power supply device is activated, and cannot be detected during operation. Therefore, if a short circuit failure occurs during operation, the failure cannot be detected until the next start-up. When the vehicle power supply device is started in the state of a short circuit failure, an inrush current flows, which may damage related electrical components.

  Therefore, the embodiment aims to detect a short-circuit failure of CHS during operation of the apparatus (during vehicle operation).

  The CHS is turned off for an extremely short time during the operation of the apparatus, and the presence or absence of a short circuit failure of the CHS is confirmed based on the change in the filter capacitor voltage.

  That is, a vehicle power supply device according to an embodiment includes a CHS unit including a resistor and a self-extinguishing semiconductor short-circuit switch for short-circuiting the resistor, and a direct current supplied from the overhead line via the CHS unit. An inverter that converts electric power into AC power, a filter capacitor connected in parallel to the DC side terminal of the inverter, a voltage detector that detects a DC side input voltage of the inverter, and a control unit that controls the shorting switch The control unit turns off the short-circuiting switch in a conductive state for a predetermined time, measures the filter capacitor voltage with the voltage detector before turning off the switch and during the turning-off period, When the voltage difference between on and off is smaller than a predetermined value, it is determined that the shorting switch has a short circuit failure.

It is a block diagram which shows the structure of the vehicle power supply device of 1st Embodiment. It is a figure which shows the structural example of the control part of 1st Embodiment. It is a timing chart which shows operation | movement of the control part of 1st Embodiment. It is a timing chart which shows the modification of operation | movement of the control part of 1st Embodiment. It is a figure which shows the structure of the control part of 2nd Embodiment. It is a timing chart which shows operation of a control part of a 2nd embodiment. It is a block diagram which shows the structure of the power supply device for vehicles of 3rd Embodiment.

  Hereinafter, a vehicle power supply device according to an embodiment will be described with reference to the drawings. The CHS failures include a short-circuit failure (not in an OFF state) and an open failure (not in an ON state). In the embodiment, a short-circuit failure is targeted.

  FIG. 1 is a block diagram showing the configuration of the first embodiment of the vehicle power supply device.

  DC power is supplied from the overhead line to the vehicle power supply device 21 via the pantograph 7, and the vehicle power supply device 21 is grounded via the wheels 9 and the like. The vehicle power supply device 21 includes a current detector 5, voltage detectors 3 and 4, a CHS unit 10, a filter capacitor 6, an inverter 8, a control unit 20, and the like. The CHS unit 10 includes a charging resistor 2 and a self-extinguishing semiconductor charging resistor short-circuit switch (CHS) 1.

  The inverter 8 is a CVCF (constant voltage constant frequency) inverter, and converts DC power supplied from the overhead line via the pantograph 7 and the CHS unit 10 into AC power. The filter capacitor 6 removes and smoothes noise contained in the DC voltage supplied to the inverter 8. The CHS unit 10 supplies the overhead line voltage to the capacitor 6 via the resistor 2 by turning off the short-circuit switch 1 for a certain period of time in order to suppress the inrush current when the charge is first stored in the input filter capacitor 6. After the charge is accumulated, the short-circuit switch 1 is turned on to short-circuit the resistor 2.

  The output AC voltage of the inverter 8 is supplied to a load such as a train air conditioner and lighting via an AC filter reactor, an AC filter capacitor, a transformer, and the like (not shown).

  The operation of this embodiment will be described below.

  When the shorting switch 1 operates in a conductive state, the voltage of the filter capacitor 6 is measured by the voltage detector 4, and the measured voltage value is input to the control unit 20 and stored in the control unit 20. . Thereafter, the control unit 20 periodically turns off the short-circuiting switch 1 for a short time. When the switch 1 is turned off, the current flowing through the shorting switch 1 flows through the charging resistor 2, and the voltage of the filter capacitor 6 is turned on by the voltage drop of the charging resistor 2. It is lower than when it was.

  The control unit 20 receives the voltage of the filter capacitor 6 measured again by the voltage detector 4 while the shorting switch 1 is turned off, and stores the measured value. The controller 20 calculates the difference between the voltage of the filter capacitor 6 before the short-circuit switch 1 is turned off and the voltage of the filter capacitor 6 while it is turned off. The shorting switch 1 is determined to have a short circuit failure.

  FIG. 2 is a diagram illustrating a configuration example of the control unit 20.

  The sample holders (SH) 11 and 12 sample the filter capacitor voltage Vc at independent timings based on the sample signals SMP1 and SMP2 from the controller 16, respectively. Since the filter capacitor voltage Vc is generally a high voltage of 1000 V or higher, it cannot be directly input to the sample holder. Therefore, the filter capacitor voltage Vc is divided by a voltage dividing resistor or the like and input to the sample holder. Similarly, in other embodiments described later, the voltage Vc or the overhead line voltage is divided and then input to the control unit.

  The subtractor 13 calculates the difference ΔV between the output signals of the sample holders 11 and 12. The comparator 14 compares the reference voltage Vref generated by the reference voltage generator 15 with the difference ΔV from the subtractor 13 and provides the comparison result V3 to the controller 16. The controller 16 generates a gate signal Vg for ON / OFF control of the shorting switch 1 (CHS). Further, the controller determines whether or not the shorting switch 1 is broken based on the comparison result V3 of the comparator 14, and if it is determined that the shorting switch is broken, the shorting switch is broken in the cab or the like. A failure detection signal Vdt indicating this is output.

  FIG. 3 is a timing chart showing the operation of this embodiment.

  The controller 16 outputs the sampling signal SMP1 (one pulse) at time t1, and as a result, the sample holder 11 samples and holds the filter capacitor voltage Vc (V1) at time t1. The controller 16 outputs the low level gate signal Vg to the shorting switch 1 at time t2. As a result, the switch 1 is turned off, and the current from the overhead wire flows through the charging resistor 2 and is supplied to the filter capacitor 6 and the inverter 8. Accordingly, the filter capacitor voltage Vc decreases due to the voltage drop of the charging resistor 2.

  The controller 16 causes the sample holder 12 to sample and hold the filter capacitor voltage Vc (V2) at time t3. The sampling signal SMP2 may be a continuous clock signal with a constant period. The subtracter 13 subtracts the voltage V2 from the filter capacitor voltage V1 and outputs a differential voltage ΔV.

  The comparator 14 compares the differential voltage ΔV from the subtractor 13 with the reference voltage Vref from the reference voltage generator 15 and outputs the comparison result V3 to the controller 16. When the controller 16 receives the high level signal as the comparison result V3, it determines that the switch 1 is not short-circuited and maintains the low level as the failure detection signal Vdet. The sample holder 12 continues to sample the filter capacitor voltage Vc every sampling period.

  The controller 16 sets the gate signal Vg to the high level at time t4 after a predetermined time from time t2 when the short-circuit switch 1 is turned off, and turns on the switch 1. As a result, the charging resistor 2 is short-circuited by the switch 1, and current flows from the overhead wire through the switch 1 and is supplied to the filter capacitor 6 and the inverter 8. Therefore, the filter capacitor voltage rises or returns to the overhead line voltage.

  When the sample holder 12 samples and holds the filter capacitor voltage V2 at time t5, the output voltages V1 and V2 of the sample holders 11 and 12 become the same. As a result, the subtracter 13 outputs 0 as the differential voltage ΔV, and the comparator 14 outputs a low level signal as the comparison result V3. The controller 16 periodically repeats the failure monitoring operation from time t1 to t5.

  Next, an operation when the shorting switch 1 is short-circuited will be described. Assume that the switch 1 has a short-circuit fault at time t6 in FIG.

  The controller 16 outputs the sampling signal SMP1 (one pulse) at time t7. As a result, the sample holder 11 samples and holds the filter capacitor voltage Vc (V1) at time t7. The controller 16 outputs the low level gate signal Vg to the shorting switch 1 at time t8. In this case, since the short-circuit switch 1 has a short-circuit failure (maintains a short-circuit state), the current from the overhead wire continues to flow through the short-circuit switch 1. Therefore, the filter capacitor voltage Vc does not change. The sample holder 12 performs sampling continuously, but its output V2 is the same as the output value of the sample holder 11. Therefore, the comparator 14 continues to output a low level signal as the comparison result V3.

  When the controller 16 does not receive a high level signal as the comparison result V3 from the comparator 14 within a predetermined time T1 from the time t8 when the shorting switch 1 is turned off, the controller 16 outputs the high level signal as the failure detection signal Vdt to the cab or the like. The switch 1 is warned that a short circuit has occurred.

  If the current flowing into the CHS unit 10 is small, even if the short-circuiting switch 1 is operating normally, the difference voltage ΔV detected when it is turned off is small, so that a reliable failure detection of the switch 1 can be performed. Can not. Therefore, the current flowing into the CHS unit 10 using the current detector 5 is measured, and the failure monitoring of the short-circuit switch 1 may be performed only when the current value is a predetermined value or more.

  Next, a modification of the first embodiment will be described with reference to FIG.

  The operations at times t1 and t2 are the same as in the above embodiment. In this modification, when the controller 16 receives a high level signal as the comparison result V3 from the comparator 14 at time t3, the controller 16 immediately returns the shorting switch 1 to the ON state. Subsequent operations are the same as in the above embodiment. Thus, in this embodiment, since the OFF period of the shorting switch 1 is shorter than that in the above embodiment, there is little energy loss due to the current flowing through the charging resistor 2.

  Next, a second embodiment will be described. FIG. 5 is a diagram illustrating a configuration of the control unit 20 according to the second embodiment.

  In the second embodiment, the sample holders 11 and 12 of FIG. 2 used in the above-described embodiment are not used. The subtracter 13 receives the filter capacitor voltage Vc and the overhead wire voltage Vw detected by the voltage detector 3.

  FIG. 6 is a timing chart showing the operation of the second embodiment. It is assumed that the overhead wire voltage Vw detected by the voltage detector 3 is always a constant value Vw1.

  The controller 16 outputs the low level gate signal Vg to the shorting switch 1 (CHS) at time t1. As a result, the switch 1 is turned off, the current from the overhead line flows through the charging resistor 2, and the filter capacitor voltage Vc decreases due to the voltage drop of the charging resistor 2. At this time, the subtractor 13 outputs a difference voltage ΔV between the overhead wire voltage Vw1 and the filter capacitor voltage Vc.

  The comparator 14 compares the differential voltage ΔV from the subtractor 13 with the reference voltage Vref from the reference voltage generator 15 and outputs the comparison result V3 to the controller 16. In response to the rise of the comparison result V3, the controller 16 sets the gate signal Vg to the high level and turns on the short-circuit switch 1. As a result, the filter capacitor voltage Vc rises, that is, returns to the overhead line voltage Vw1.

  Next, an operation when the shorting switch 1 is short-circuited will be described. Assume that the switch 1 is short-circuited at time t3 in FIG.

  The controller 16 outputs the low level gate signal Vg to the shorting switch 1 at time t4, but the switch 1 is not turned off, so that the filter capacitor voltage Vc does not change and the difference voltage ΔV does not occur. Therefore, the comparator 14 continues to output a low level signal as the comparison result V3.

  If the high level signal is not received as the comparison result V3 from the comparator 14 within the predetermined time T1 from the time t4 when the shorting switch 1 is turned off, the controller 16 outputs the high level signal as the failure detection signal Vdt to the cab or the like. The switch 1 is warned that a short circuit has occurred.

  As described above, in the second embodiment, the controller 16 sets the gate signal Vg to the high level in response to the fall of the filter capacitor voltage Vc (rise of the comparison result V3). Accordingly, the time t1 to t2 when the shorting switch 1 is off is short enough to be ignored.

  In the second embodiment, in the short-circuit fault monitoring of the short-circuit switch 1, the energy loss due to the charging resistor 2 is extremely small, and the input voltage of the inverter 8 does not substantially change.

  Next, a third embodiment will be described. The vehicular power supply device according to the third embodiment is a vehicular power supply device corresponding to an AC feeding system.

  FIG. 7 is a diagram showing a configuration of a vehicle power supply device according to the third embodiment.

  This vehicle power supply device 21 has a single-phase full-wave diode bridge rectifier circuit 22 at a power input stage, and a CHS unit 10 including a short-circuit switch of a thyristor 23 and a charging resistor 2 is connected to the subsequent stage.

  When the thyristor 23 is operating in a conductive state, the voltage detector 4 measures and stores the voltage of the filter capacitor 6. Thereafter, the gate of the thyristor 23 is turned off for a short time. Thereby, when the thyristor 23 is not short-circuited, the thyristor 8 is turned off when the anode voltage of the thyristor 23 falls below the cathode voltage, and the current flowing through the thyristor 23 passes through the charging resistor 2. As a result, the voltage of the filter capacitor 6 decreases.

  While the gate of the thyristor 23 is turned off, the voltage of the filter capacitor 6 is measured again by the voltage detector 4 and stored. The difference between the voltage of the filter capacitor 6 before the gate of the thyristor 23 is turned off and the voltage of the filter capacitor 6 when the gate is turned off is calculated, and when the value is below a certain value, the thyristor 8 Judge that a short circuit has occurred.

  The detailed operation of the control unit 21 of the third embodiment is omitted because it is the same as that of the first and second embodiments described above.

  As described above, according to the embodiment of the present invention, it is possible to detect a short-circuit failure of the charging resistor short-circuit switch during operation of the power supply device (during vehicle operation).

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Switch for charging resistance short circuit, 2 ... Resistance for charging, 3, 4 ... Voltage detector, 5 ... Current detector, 6 ... Filter capacitor, 8 ... Inverter.

Claims (9)

A CHS unit including a resistor and a self-extinguishing semiconductor short-circuit switch for short-circuiting the resistor;
An inverter that converts DC power supplied from an overhead wire through the CHS unit into AC power;
A filter capacitor connected in parallel to the DC side terminal of the inverter;
A voltage detector for detecting a DC side input voltage of the inverter;
A controller for controlling the shorting switch;
The control unit turns off the short-circuiting switch in a conductive state for a predetermined time, measures the filter capacitor voltage with the voltage detector before turning off the switch and during the turning-off period, When the voltage difference is smaller than a predetermined value, it is determined that the shorting switch has a short circuit failure. A current detector for detecting an input current flowing into the CHS unit;
2. The vehicle power supply device according to claim 1, wherein the control unit determines that the short-circuit switch is short-circuited only when the input current is equal to or greater than a predetermined current value.   When the voltage difference between the on and off of the shorting switch exceeds a predetermined value, the control unit immediately turns off the shorting switch without waiting for a predetermined time to turn off the shorting switch. The vehicle power supply device according to claim 1, wherein the vehicle power supply device is turned on. A CHS unit including a resistor and a self-extinguishing semiconductor short-circuit switch for short-circuiting the resistor;
An inverter that converts DC power supplied from an overhead wire through the CHS unit into AC power;
A filter capacitor connected in parallel to the DC side terminal of the inverter;
A first voltage detector for detecting a filter capacitor voltage generated between the terminals of the filter capacitor;
A second voltage detector for detecting an overhead wire voltage input to the shorting switch;
A controller for controlling the shorting switch;
The control unit turns off the short-circuiting switch in a conductive state for a predetermined time, detects a current input side (overhead wire) voltage of the short-circuiting switch detected by the second voltage detector, and the first voltage detector. When the voltage difference between the current output side of the shorting switch detected during the OFF period is measured and the voltage difference between the input side and output side voltages is smaller than a predetermined value, the shorting switch is short-circuited. A power supply device for a vehicle that is judged to be in operation. A current detector for detecting an input current flowing into the CHS unit;
5. The vehicle power supply device according to claim 4, wherein the control unit determines a short-circuit failure of the short-circuit switch only when the input current is equal to or greater than a predetermined current value.   When the voltage difference between the input-side and output-side voltages of the short-circuit switch exceeds a predetermined value, the control unit does not wait for a predetermined time to turn off the short-circuit switch, and immediately 6. The vehicle power supply device according to claim 4, wherein the short-circuit switch is turned on. A diode bridge rectifier circuit that converts the AC voltage supplied from the overhead line into a DC voltage by full-wave rectification;
A CHS unit including a resistor and a short-circuit switch comprising a thyristor for short-circuiting the resistor;
An inverter that converts DC power supplied from the diode bridge rectifier circuit through the CHS unit into AC power;
A filter capacitor connected in parallel to the DC side terminal of the inverter;
A voltage detector for detecting a DC side input voltage of the inverter;
A controller for controlling the shorting switch;
The control unit turns off the short-circuiting switch in a conductive state for a predetermined time, measures the filter capacitor voltage with the voltage detector before turning off the switch and during the turning-off period, When the voltage difference is smaller than a predetermined value, it is determined that the shorting switch has a short circuit failure. A current detector for detecting an input current flowing into the CHS unit;
8. The vehicle power supply device according to claim 7, wherein the control unit determines that the short-circuit switch is short-circuited only when the input current is equal to or greater than a predetermined current value.   When the voltage difference between the on and off of the shorting switch exceeds a predetermined value, the control unit immediately turns off the shorting switch without waiting for a predetermined time to turn off the shorting switch. The vehicle power supply device according to claim 7, wherein the vehicle power supply device is turned on.

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