JP2010041817A - Power supply unit for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply unit for a vehicle, which continues operation of an inverter unit longer than a contact loss guaranteeing time defined by a filter capacitor even if an overhead contact line is bounced on a current collector. <P>SOLUTION: DC power supplied from an overhead contact line 1 is received by a current collector 2, and converted into AC power by a VVVF inverter 17 to drive a motor of an electric train, and is converted into AC power by an inverter unit 12. The inverter unit 12 inputs DC power via a filter capacitor 11 and converts the DC power into AC power, and supplies the converted power to an in-vehicle load 13. A battery 20 supplies the DC power to the filter capacitor 11 when the current collector 2 is bounced on the overhead contact line 1. Further, a DC-DC converter 19 charges the battery 20 with the DC power supplied from the overhead contact line 1 when the current collector 2 is not bounced on the overhead contact line 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicular power supply device for an electric vehicle constituted by an inverter device.

  In general, a vehicle power supply device for an electric vehicle receives DC power supplied from an overhead wire with a current collector, converts it into AC power with an inverter unit connected in parallel with a VVVF inverter that drives a train motor, It is comprised so that electric power may be supplied to the vehicle interior load. The inverter unit inputs DC power through a filter capacitor, converts it into AC power, and supplies power to the in-vehicle load (see, for example, Patent Document 1).

  FIG. 4 is a configuration diagram illustrating an example of a conventional vehicle power supply device. DC power is received from the overhead line 1 by the current collector 2, and the DC power received by the current collector 2 is converted into a switch 3, an input overcurrent protection fuse 4, an input electromagnetic contactor 5, a DC filter reactor, a charging resistor 7. The filter capacitor 11 is charged through the charging resistor 8. When the filter capacitor 11 is charged with a certain voltage, the charging resistor short-circuit thyristor 9 is closed, and the switching of the semiconductor element of the inverter unit 12 converts DC power into three-phase AC power and supplies the load 13 with power. . Reference numeral 10 denotes a contactor for discharging a filter capacitor.

  On the other hand, the DC power received by the current collector 2 is supplied to the VVVF inverter 17 via the VVVF switch 14, the VVVF input overcurrent protection fuse 15, and the high-speed circuit breaker 16, and the VVVF inverter 17 is shown in the figure. Drive the omitted motor.

  FIG. 5 is an operation explanatory diagram when the current collector is disconnected in the conventional vehicle power supply device. In the prior art, when the current collector 2 is not disconnected from the overhead line 1 and the inverter unit 12 is in operation (S1) and the current collector 2 is disconnected from the overhead line 1 (S2), the DC power from the current collector 2 is reduced. Since the supply is cut off and the inverter unit 12 continues to supply AC power to the load 13, the voltage charged in the filter capacitor 11 decreases (S3). When the voltage of the filter capacitor 11 decreases to the filter capacitor low voltage set value FCLVD (S4), the inverter unit 12 stops (S5). The filter capacitor low voltage set value FCLVD is a voltage at which the filter capacitor 11 cannot maintain a predetermined AC voltage.

Here, the time from when the power supply of DC power is cut off because the current collector 2 is disconnected from the overhead line 1 until the inverter unit 12 stops (separation guaranteed time) t is expressed by the following equation (1). .

P: inverter unit load capacity, φ: power factor, n: efficiency, FCV: filter capacitor voltage, FCLVD: filter capacitor low voltage set value
JP-A-6-261403

  As described above, the voltage charged in the filter capacitor 11 is consumed by the load 13 of the inverter unit 12, and the inverter unit 12 stops when the filter capacitor voltage FCV drops to the filter capacitor low voltage set value FCLVD. Then, the time (separation guarantee time) t from when the current collector 2 is disconnected until the inverter unit 12 stops is determined by the capacity of the filter capacitor 11 as shown in the equation (1). The line separation guarantee time is usually about several tens of ms. Therefore, when further disconnection occurs during traveling, the inverter unit 12 stops and power cannot be temporarily supplied to the load 13 side.

  As described above, when the current collector 2 is disconnected from the overhead wire 1 during train traveling and the time elapses, the power supply to the inverter unit 12 is cut off and the inverter unit 12 stops.

  An object of the present invention is to provide a vehicular power supply device that can continue the operation of an inverter unit for a longer time than a disconnection guarantee time determined by a filter capacitor even when the current collector is disconnected from the overhead line.

  The power supply device for a vehicle according to the present invention receives DC power supplied from an overhead wire by a current collector and converts it into AC power by an inverter unit connected in parallel with a VVVF inverter that drives a train motor. In a vehicle power supply apparatus that inputs DC power through a filter capacitor, converts the AC power into AC power, and supplies power to an in-vehicle load, for supplying DC power to the filter capacitor when the current collector is disconnected from the overhead line A battery and a DC / DC converter for charging the battery with DC power supplied from the overhead line when the current collector is not disconnected from the overhead line.

  According to the present invention, it is an object of the present invention to provide a vehicular power supply device that can continue the operation of an inverter unit for a longer time than the wire separation guarantee time determined by the filter capacitor even when the current collector is disconnected from the overhead wire.

  FIG. 1 is a configuration diagram showing an example of a vehicle power supply apparatus according to an embodiment of the present invention. The vehicle power supply apparatus according to the embodiment of the present invention is provided by adding a backflow prevention diode 18, a DC / DC converter 19, a battery 20, and a diode 21 to the conventional example shown in FIG. . The same elements as those in FIG. 4 are denoted by the same reference numerals, and redundant description is omitted.

  The DC / DC converter 19 is connected to the input side of the VVVF inverter 17 and receives DC power received by the current collector 2. The DC / DC converter 19 converts DC power received by the current collector 2 into DC power that can be stored in the battery 20, and is supplied from the overhead wire 1 when the current collector 2 is not disconnected from the overhead wire 1. The battery 20 is charged with the DC power.

  When the current collector 2 is not disconnected from the overhead wire 1, the battery 20 is charged by converting DC power received by the current collector 2 into DC power suitable for the battery 20 by the DC / DC converter 19. When the current collector 2 is disconnected from the overhead wire 1, DC power is supplied to the filter capacitor 11 provided on the input side of the inverter unit 12 via the diode 21. The backflow prevention diode 18 prevents the backflow of DC power to the current collector 2 side when supplying DC power from the battery 20 to the filter capacitor 11.

  FIG. 2 is an explanatory diagram showing an example of the operation at the time of disconnecting the current collector in the vehicle power supply device according to the embodiment of the present invention. During the operation of the inverter unit 12 with the current collector 2 not disconnected from the overhead wire 1 (S1), the DC / DC converter 19 charges the battery 20 with DC power. When the current collector 2 is disconnected from the overhead wire 1 in this state (S2), the supply of DC power from the current collector 2 is cut off, and the inverter unit 12 continues to supply AC power to the load 13, so the filter capacitor 11 is charged. The applied voltage is reduced (S3).

  When the voltage of the filter capacitor 11 decreases and the battery voltage becomes equal to or lower than the voltage of the filter capacitor 11, DC power is supplied from the battery 20 to the filter capacitor 11 via the diode 21 (S4). Then, the inverter unit 12 is continuously operated until the storage amount of the battery 20 decreases and the filter capacitor voltage becomes the filter capacitor low voltage set value FCLVD (S5).

  According to this example, when the battery 20 is provided and the current collector 2 is disconnected from the overhead wire 1, DC power is supplied from the battery 20 to the filter capacitor 11, so that the inverter unit 12 is longer than the disconnection guarantee time determined by the filter capacitor 11. Can continue driving. For example, the inverter unit 12 has been stopped at a disconnection of several tens of ms in the past, but in this example, the inverter unit 12 can continue to operate even at a disconnection of several seconds, and the load on the inverter unit 12 can be prevented from stopping.

FIG. 3 is an explanatory view showing another example of the operation at the time of disconnecting the current collector in the vehicle power source apparatus according to the embodiment of the present invention. In another example, instead of step S5 of the example shown in FIG. 2, when the storage amount of the battery 20 decreases and the filter capacitor voltage decreases, before the battery voltage becomes the filter capacitor low voltage set value FCLVD, The inverter unit 12 is stopped (S5 ′). The same steps as those in FIG. 2 are denoted by the same reference numerals, and redundant description is omitted.
The inverter unit 12 monitors the battery voltage, and when the current collector 2 is disconnected from the overhead wire 1, when the battery voltage becomes a value obtained by adding a margin value to the filter capacitor low voltage setting value FCLVD, that is, the battery The inverter unit 12 is stopped before the voltage reaches the filter capacitor low voltage setting value FCLVD (S5 ′).

  According to another example, in addition to the effect of the example shown in FIG. 2, when the current collector 2 is disconnected from the overhead wire 1, it is possible to prevent the battery 20 from being excessively discharged and to prevent the battery voltage from being lowered excessively. it can.

The block diagram which shows an example of the power supply device for vehicles concerning embodiment of this invention. Explanatory drawing which shows an example of the operation | movement at the time of a collector disconnection in the power supply device for vehicles concerning embodiment of this invention. Explanatory drawing which shows another example of the operation | movement at the time of a collector disconnection in the vehicle power supply device concerning embodiment of this invention. The block diagram which shows an example of the conventional vehicle power supply device. Operation | movement explanatory drawing at the time of the current collector disconnection in the conventional vehicle power supply device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Overhead wire, 2 ... Current collector, 3 ... Switch, 4 ... Input overcurrent protection fuse, 5 ... Input magnetic contactor, 6 ... DC filter reactor, 7 ... Charging resistor, 8 ... Charging resistor, 9 ... Charging Resistor short-circuit thyristor, 10 ... Filter capacitor discharge contactor, 11 ... Filter capacitor, 12 ... Inverter unit, 13 ... Load, 14 ... VVVF switch, 15 ... VVVF input overcurrent protection fuse, 16 ... High speed Circuit breaker, 17 ... VVVF inverter, 18 ... Backflow prevention diode, 19 ... DC / DC converter, 20 ... Battery, 21 ... Diode

Claims (2)

  The DC power supplied from the overhead line is received by the current collector, converted to AC power by the inverter unit connected in parallel with the VVVF inverter that drives the electric motor of the train, and the inverter unit receives the DC power through the filter capacitor. In the vehicle power supply device for converting into AC power and supplying power to an in-vehicle load, a battery for supplying DC power to the filter capacitor when the current collector is disconnected from the overhead wire, and the current collector is the overhead wire And a DC / DC converter for charging the battery with DC power supplied from the overhead line when not disconnected from the vehicle.   2. The vehicle power supply device according to claim 1, further comprising a backflow prevention diode for preventing a direct current from flowing backward from the battery to the overhead wire.

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