JP4218610B2 - Electric vehicle power supply - Google Patents

Description

  The present invention relates to a power supply device for an electric vehicle such as an electric vehicle or a hybrid vehicle, and more particularly to a power supply device for an electric vehicle suitable for charging with an external power supply.

  Conventionally, there has been proposed an electric vehicle power supply device including a high voltage battery for supplying electric power to a vehicle driving motor and a low voltage battery for supplying electric power to a vehicle auxiliary machine (see Patent Documents 1 and 2).

  In Patent Document 1, a high-voltage battery that supplies engine starting power and high-voltage traveling motor drive power and a low-voltage battery that supplies power to auxiliary motors and control devices are provided to enable high-voltage battery charging by a rescue vehicle. As a hybrid vehicle charging device, a DC-DC converter for boosting low voltage DC power from a low voltage battery of a rescue vehicle and charging the high voltage battery Provided. The low-voltage power of the low-voltage battery of the rescue vehicle is fed directly to the low-voltage DC power input terminal of the DC-DC converter through the booster cable without going through the on-vehicle low-voltage battery.

In Patent Document 2, in order to realize reverse power transmission from a low-voltage battery to a high-voltage battery with a simple circuit configuration, a high-voltage battery that supplies engine starting power and high-voltage driving motor drive power to an auxiliary motor In a power source device for a two-battery hybrid electric vehicle having a low-voltage battery that is fed through an auxiliary motor driving inverter device, a high voltage battery is obtained by rectifying the AC power received from the auxiliary motor driving inverter device with a rectifier. To charge. That is, a DC-DC converter device that transmits power from a low-voltage battery to a high-voltage battery uses the auxiliary motor driving inverter device that is fed from the low-voltage battery and transmits power to the auxiliary motor to generate DC power from the low-voltage battery. Since it converts into alternating current power, the circuit structure of this DC-DC converter apparatus can be simplified by circuit sharing.
JP 2000-358304 A JP 2000-358305 A

  By the way, when the high-voltage battery of a hybrid vehicle or an electric vehicle equipped with a high-voltage battery as in the above-described conventional example causes battery exhaustion, the rescue vehicle is a vehicle equipped with such a high-voltage battery. The high voltage battery of the rescue vehicle and the high voltage battery of the host vehicle are preferably connected and charged.

  However, if charging is performed by directly connecting an external power source such as a high-voltage battery of the rescue vehicle and the high-voltage battery of the host vehicle, the voltage of the battery of the host vehicle is reduced. The voltage difference with the high-voltage battery of the own vehicle is large, and an inrush current flows on the circuit, which may damage the circuit.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a power supply device for an electric vehicle that can be charged by directly connecting an external power supply and a high-voltage battery of the host vehicle.

The present invention provides an inverter for driving a vehicle driving electric motor by converting supply power supplied via positive and negative power supply buses into alternating current, and via positive and negative power supply buses to the inverter. A power supply device for an electric vehicle comprising a battery for supplying electric power, wherein a capacitor is connected in parallel between a positive electrode side and a negative electrode power supply bus between the battery and the inverter, and the positive electrode side connects the capacitor and the inverter Further, the inverter-side end of each power supply bus on the negative electrode side is detachably connected to the inverter by a connector, and the battery can be connected to an external power source for charging the battery via each power supply bus and the connector .

Therefore, in the present invention, an inverter that converts the supplied power supplied via the positive and negative power supply buses into alternating current to drive the vehicle driving motor, and positive and negative power supply buses to the inverter. In the electric vehicle power supply device including a battery for supplying electric power via a capacitor, a capacitor is connected in parallel between the positive and negative power supply buses between the battery and the inverter, and the capacitor and the inverter are connected The inverter side end of each power supply bus on the positive side and the negative side is connected to the inverter so that it can be removed by a connector, and the battery can be connected to an external power source for charging the battery via the power supply bus and the connector. Inrush current generated during charging with an external power supply connected to each power supply bus can be suppressed by the capacitor.
The capacitor may be a smoothing capacitor built in the inverter casing or a smoothing capacitor having similar performance may be installed in parallel between the high-voltage cables, and existing components can be used. It can be connected to an external power supply without the need for a high-voltage cable dedicated to charging, and there is little cost increase.
In addition, the inverter-side end of each of the positive and negative power feeding buses connecting the capacitor and the inverter is detachably connected to the inverter by a connector, and the battery is connected to the external power source via the power feeding bus and the connector. Since the battery can be connected, the battery can be charged without requiring a separate connection line dedicated for charging at the time of charging, and can be configured at low cost.

  Hereinafter, an embodiment of a power supply device for an electric vehicle according to the present invention will be described with reference to FIGS. FIG. 1 is a system configuration diagram of a hybrid vehicle including an electric vehicle power supply device to which the present invention is applied, FIG. 2 is an arrangement layout diagram of each element of the electric vehicle power supply device, and FIGS. 3 and 4 are diagrams of the electric vehicle power supply device. An end view and a perspective view showing a connector shape for connecting the high voltage cable to the inverter, and FIG. 5 are explanatory views showing a connection state to the rescue vehicle (external power source).

In FIG. 1, the system configuration of the hybrid vehicle includes a drive device 1 including an engine 2, a generator 3, a motor 4, a planetary gear 5, and the like, and an output unit connected to a drive wheel 8 via a differential gear 6 and an axle 7. And an inverter 10 for driving the generator 3 and the motor 4 of the driving device 1 and a high voltage battery 11 for storing input / output power to the inverter 10.

For example, the driving device 1 can be connected to one of the three elements of the planetary gear device 5 with the output shaft of the engine 2, and the other element can operate as an engine-driven generator, a starter motor , or a regenerative braking generator. A simple generator 3 is connected, a torque assist motor 4 is connected to the remaining one element, and an output unit is connected to a differential gear 6.

  The inverter 10 exchanges DC power with the high voltage battery 11 and also exchanges AC power with the generator 3, and exchanges DC power with the high voltage battery 11 and exchanges AC power with the motor 4. The three-phase inverter circuit is configured to be controlled by the vehicle controller 12.

  The main relay 13 capable of shutting off the input / output of the high voltage battery 11 and the inverter 10 are connected by high voltage cables 15 and 16 with a smoothing capacitor 14 interposed therebetween. The high voltage cable 15 is connected to a low voltage battery 18 via a DC-DC converter 17, and the low voltage battery 18 is charged by power supply from the high voltage battery 11 via the DC-DC converter 17. The high voltage cables 15 and 16, the smoothing capacitor 14, the DC-DC converter 17, the main relay 13, the high voltage battery 11, and the low voltage battery 18 constitute an electric vehicle power supply device and are controlled by the power supply controller 20. It is composed. The vehicle controller 12 and the power supply controller 20 are configured to be supplied with power from the low voltage battery 18.

  The smoothing capacitor 14 is connected in parallel between the inverter 10 and the high voltage battery 11 and functions to smooth the power when supplying and receiving power between the inverter 10 and the high voltage battery 11. The smoothing capacitor 14 is installed outside the inverter 10 casing, which is installed in the inverter 10 casing, which suppresses voltage fluctuations of the high-voltage battery 11 caused by the switching relay in the inverter 10 being turned on and off.

  In the arrangement shown in FIG. 2, the inverter 10, the smoothing capacitor 14, and the high voltage battery 11 are arranged. That is, the inverter 10 is disposed in the engine room in front of the vehicle, and the high voltage battery 11 is disposed in any position in the trunk room or around the trunk room, for example, behind the vehicle. The smoothing capacitor 14 is disposed above the engine room, and the smoothing capacitor 14 is connected to the high voltage battery 11 and the inverter 10 via high voltage cables 15 and 16, respectively.

  The inverter 10 and the high voltage cable 16 from the smoothing capacitor 14 are connected via a detachable connector 21. As shown in FIGS. 3 and 4, the connector 21 has a shape in which an insulating portion 23 and a current-carrying portion 24 made of a conductor are cut away from each other over a predetermined connection region, leaving a plurality of predetermined angle ranges. Constitute. For example, in the connector shape shown in FIG. 3A and FIG. 4, the portions where the insulating portions 23 and the current-carrying portions 24 made of a conductor are left and the portions that are cut off are alternately arranged for each range of 90 degrees. It is configured to do. Further, in the connector shape shown in FIG. 3B, the portions where the insulating portions 23 and the current-carrying portions 24 made of a conductor are left and the portions that are cut off are alternately arranged for each angle of 45 degrees. is doing. The shape of the connector 21 for the high voltage cable 16 prevents, for example, a short circuit due to a direct connection between the positive electrode side and the negative electrode side of the high voltage cable 16. For example, FIG. 3A and FIG. As shown in FIG. In the connector shape from the inverter 10 side, the shape corresponds to the connector 21 on the positive electrode side and the negative electrode side of the high voltage cable 16 so that the current-carrying portions 24 can contact each other.

  The operation when the high-voltage battery of the electric vehicle power supply device having the above configuration is urgently charged from an external power source will be described below with reference to FIG.

  First, as shown in FIG. 5, for example, as shown in FIG. 5, the rescue vehicle is changed to the failed vehicle so that the mounting positions of the smoothing capacitors 14 of both the failed vehicle (own vehicle) in which the high voltage battery 11 is raised and the rescue vehicle approach each other. Stop the vehicle.

  Next, the main relays 13 that enable the high voltage battery 11 and the smoothing capacitor 14 of the host vehicle and the rescue vehicle to be connected and disconnected are switched to the cutoff side by the power supply controller 20 respectively. By this blocking operation, the high voltage cable 16 of each vehicle is disconnected from the high voltage battery 11. In this state, the connector 21 connecting the inverter 10 and the high voltage cable 16 is removed from each vehicle. The connector 21 and the high-voltage cable 16 can be easily removed and removed because the inverter 10 is disposed near the front end of the vehicle and the smoothing capacitor 14 is disposed above the engine room.

  Next, the high-voltage cables 16 of both vehicles are connected to the positive-side and negative-side connectors 21 to electrically connect the high-voltage cables 16 to each other. In connecting the connectors 21, it is necessary to connect the positive connectors 21 and the negative connectors 21 together. In this structure, the connectors 21 on the positive electrode side are shaped to be fitted to each other. However, since the connector shape of the positive electrode side connector 21 and the negative electrode side connector 21 is different, the connectors are erroneously different in polarity. Connection between 21 can be avoided. This completes preparation for charging.

  Then, charging is started from the high-voltage battery 11 of the rescue vehicle to the high-voltage battery 11 of the failed vehicle by switching the main relays 13 of both vehicles to the conduction side for charging. At the start of charging, since the voltage of the high-voltage battery 11 on the failed vehicle side has decreased, an inrush current tends to flow from the high-voltage battery 11 on the rescue vehicle side to the high-voltage battery 11 on the failed vehicle side. Since the large-capacity smoothing capacitor 14 is arranged in parallel on the rescue vehicle side and the broken vehicle side, the inrush current can be effectively suppressed.

  After a predetermined time has elapsed since the start of emergency charging, or if the amount of power transmitted to the high voltage battery 11 exceeds a predetermined value, the power controller 20 of each vehicle shuts off each main relay 13 to stop power transfer. , Terminate the charging state. An inrush current due to a sudden change in the voltage of the high voltage cable 16 when the main relay 13 is cut off can also be effectively suppressed by the smoothing capacitor 14. After that, if the connector 21 connection between the high voltage cables 16 is disconnected and the high voltage cable 16 is connected to the inverter 10 of each vehicle via the connector 21, the failed vehicle operates the generator 3 with the power of its own high voltage battery 11. Thus, the engine 2 can be started. Further, the voltage fluctuation on the high voltage battery 11 side due to the switching relay when the DC power from the high voltage battery 11 is converted to AC power by the inverter 10 is caused by the operation of the smoothing capacitor 14 connected in parallel with the inverter 10. It can be similarly suppressed.

  In the above-described embodiment, the external power source that is charged from the high-voltage battery 11 from the rescue vehicle has been described. However, although not shown, the external power source is also detached from the inverter 10 at the charging station (charging station). In addition, the connector 21 of the high voltage cable 16 is connected to the connector of the charging stand so that the high voltage battery 11 can be easily charged directly from the charging stand.

  In the above embodiment, the smoothing capacitor built in the inverter 10 is separated from the inverter 10 and connected in parallel to the high voltage cable 16 as a smoothing capacitor. The smoothing capacitor may be left as it is, and a new smoothing capacitor having the same performance may be prepared and connected to the high voltage cable 16 in parallel.

  In the present embodiment, the following effects can be achieved.

  (A) Inverter 10 that drives the vehicle driving motor (4) by converting the supplied power supplied through the positive and negative power feeding buses (16) into alternating current; And a battery 11 for supplying electric power via a power feeding bus (16) on the side, a capacitor between the power feeding bus (16) on the positive side and the negative side between the battery 11 and the inverter 10 14 are connected in parallel, and an external power supply for charging the battery can be connected to each of the positive and negative power supply buses (16) between the capacitor 14 and the inverter 10, so that each power supply bus (16) An inrush current generated during charging with an external power supply connected can be suppressed by the capacitor 14. The capacitor 14 may be a smoothing capacitor built in the casing of the inverter 10 or a smoothing capacitor 14 having similar performance may be installed in parallel between the high-voltage cables 16, and existing components can be used. In addition, it can be connected to an external power supply without the need for a high-voltage cable dedicated to charging with a capacitor, and the cost increase can be reduced.

  (B) The inverter 10 side ends of the positive and negative power supply buses (16) connecting the capacitor 14 and the inverter 10 are detachably connected to the inverter 10 by a connector 21, and the batteries 11 are connected Since the external power supply can be connected via the power supply bus (16) and the connector 21, the battery 11 can be charged without requiring a separate connection line for charging at the time of charging, and can be configured at low cost.

  (C) As the terminal shape of the connector 21, the positive electrode side connector 21 connected to the positive electrode side power supply bus (16) and the negative electrode side connector 21 connected to the negative electrode side power supply busbar are made different in shape during charging. Since the positive and negative electrodes of the high voltage cable 16 can be easily distinguished from each other and cannot be connected to each other, the risk of erroneous assembly can be reduced.

  (D) Since the connector 21 connected to the inverter 10 and each power supply bus (16) connected to the connector 21 are arranged on the front side of the engine room of the vehicle, the high voltage cable 16 can be easily taken out from the front of the vehicle. Wiring work for charging can be easily performed.

  In the above embodiment, the vehicle power supply device applied to a hybrid vehicle including the high voltage battery 11 is described as the electric vehicle. However, although not shown, the vehicle drive motor is driven by battery power other than the high voltage battery 11. It may be a vehicle power supply device applied to a so-called electric vehicle.

1 is a system configuration diagram of a hybrid vehicle including an electric vehicle power supply device according to an embodiment of the present invention. The arrangement layout figure of each element of the power supply device for electric vehicles similarly. The end view which shows an example (A) of a connector shape which connects the high voltage cable of the power supply device for electric vehicles to an inverter, and (B). The perspective view of an example of the connector shape which connects the high voltage cable of the power supply device for electric vehicles to an inverter. The state figure at the time of the connection to a rescue vehicle (external power supply).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive device 2 Engine 3 Generator 4 Motor 5 Planetary gear device 6 Differential gear 7 Axle 8 Drive wheel 10 Inverter 11 High voltage battery as battery 13 Main relay 14 Smoothing capacitor as capacitor 15, 16 High voltage cable (power supply bus)
21 Connector

Claims (3)

An inverter that drives the vehicle driving motor by converting supply power supplied via the positive and negative power supply buses to AC, and supplies power to the inverter via the positive and negative power supply buses In an electric vehicle power supply device comprising a battery,
A capacitor is connected in parallel between the positive and negative power supply buses between the battery and the inverter,
The inverter side end of each feeding bus on the positive electrode side and the negative electrode side connecting the capacitor and the inverter is detachably connected to the inverter by a connector,
An electric vehicle power supply device characterized in that the battery can be connected to an external power supply for battery charging via each of the power supply buses and the connector . The terminal shape of the connector is different between the positive electrode side connector connected to the positive electrode side power supply bus and the negative electrode side connector connected to the negative electrode side power supply bus . Electric vehicle power supply device. 3. The electric vehicle power supply device according to claim 1, wherein the connector connected to the inverter and each power supply bus connected to the connector are arranged on the front side of the engine room of the vehicle.

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