JPH11355901A - Power controller for electric car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend the travel distance of an electric car, and to reduce the size and the weight, by using a power control circuit by the use of a switching power circuit for driving auxiliary apparatuses. using a power source in common with a running motor, and simplifying an auxiliary apparatus system. SOLUTION: An A power control circuit 11 is composed of a switching power circuit composed of a chopper circuit or inverter circuit and an A induction coil 11L, depending on an A electric load 12, and performs control by an A control commanding means 13. And the A power control circuit 11 converts the output of a main battery 1, and supplies it to the A electric load 12 directly. Consequently, it becomes possible to simplify the apparatus, and to reduce its size and weight, since connecting distributing wires from the main battery 1 can be partially used in common by power control circuits 11, 21, a power converting apparatus 2 for running motors, and so on. Besides, it is possible to reduce power consumption of the battery, and to extend a travel distance, since power supply to auxiliary apparatuses not in use is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control device for supplying power to auxiliary equipment in an electric vehicle running on a battery.

[0002]

2. Description of the Related Art An electric vehicle running on a battery has a limited amount of stored electric power, and thus has a problem that its traveling distance is shorter than that of an engine vehicle. As a solution to this problem, besides a method of operating a traveling motor with higher efficiency (Japanese Patent Application Laid-Open No. 8-228404, etc.), a method of increasing the amount of power stored in a vehicle using a detachable auxiliary high-voltage battery, for example (Japanese Patent Application Laid-Open No. H08-228404). 7-1
No. 23514), or a method for reducing the size and weight of auxiliary devices not directly involved in running (Japanese Patent Application Laid-Open Nos. 7-170611, 7-212901, etc.).

[0003]

However, in order to secure a wider cabin and luggage compartment of the vehicle, the installation space of the on-vehicle equipment must be reduced due to restrictions on the size of the vehicle. As described in the publication, it is not always possible to mount a large number of batteries on a vehicle or to pull a battery cart.

On the other hand, in the case of auxiliary equipment, it is effective to reduce the size and weight of the system by, for example, eliminating the battery for auxiliary equipment that is heavy. However, when a DC-DC converter is used as disclosed in Japanese Patent Application Laid-Open No. 7-170611, a battery for auxiliary equipment becomes unnecessary. However, since a transformer, which is also a heavy object, is provided inside the battery, the rate of improvement is small. . In addition, the size of the transformer must be increased in response to an increase in the assumed load. In addition, a method using a constant current inverter as disclosed in Japanese Patent Application Laid-Open No.
It can be regarded as a kind of C-DC converter.

It is an object of the present invention to provide a power control device for an electric vehicle that extends the mileage of a vehicle by improving a power supply for driving auxiliary equipment.

[0006]

According to the present invention, in order to extend the mileage of an electric vehicle, a power control circuit using a switching power supply circuit is used to drive auxiliary equipment. Simplify the equipment system,
This is installed in the cooling device of the power converter for driving the traveling motor, and the size and weight are reduced.

[0007] Further, the auxiliary equipment is distributed to several circuit groups to reduce the capacity and optimize the capacity of the power control circuit and individually control the circuit groups.

Further, when the load to be driven is inductive, it is operated as an induction coil of a power control circuit, thereby eliminating a single induction coil, thereby reducing the size and weight of the power control circuit.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of this embodiment. The main battery 1 outputs a DC of about 100 to 350 V specified for each vehicle. The traction motor power converter 2 controls the output of the main battery 1 to drive the traction motor 3 to drive the vehicle.

The A power control circuit 11 comprises a switching power supply circuit such as a chopper circuit or an inverter circuit according to the A electric load 12, and is controlled by the A control command means 13. The A power control circuit 11 converts the output of the main battery 1 and supplies it directly to the A electric load 12. 11L is an A induction coil constituting the A power control circuit 11.

FIG. 2 shows an embodiment in which the A electric load 12 has no electromagnetic induction and the A power control circuit 11 is a step-down chopper circuit. The A power control circuit 11 mainly includes an A induction coil 11L, an A switching element 14, and an A free wheel diode 15. The A switching element 14 interrupts the load current flowing to the A electric load 12 by the A control command means 13.

When the A-switching element 14 is conducting, the load current flows from the main battery 1 to the A-switching element 14 → A induction coil 11L → A electric load 12 → the main battery 1.

The load current when the A switching element 14 is in a disconnected state flows through the A induction coil 11L → A electric load 12 → A free wheel diode 15 → A induction coil 11L due to the electromagnetic induction of the A induction coil 11L.

FIG. 3 shows an embodiment in which the B power control circuit is a boost chopper circuit. The B power control circuit 21 mainly includes a B induction coil 21L, a B switching element 24, and a B backflow prevention diode 25. The B switching element 24 is controlled by the B control
The induced current flowing through L is intermittent.

The current flowing when the B switching element 24 is in the conduction state is: the main battery 1 → the B switching element 24 → the B induction coil 21L → the main battery 1.

The current flowing when the B switching element 24 is in the disconnected state is determined by the main battery 1 → the B induction coil 21L →
The B backflow prevention diode 25 → the B electric load 22 → the main battery 1. At this time, the sum of the voltage of the main battery 1 and the voltage induced by the electromagnetic induction of the B induction coil 21L is applied to the B electric load 22.

FIG. 4 shows that the C electric load 32 has electromagnetic induction like a motor or an incandescent lamp, and the C electric power control circuit 3
This is an embodiment in which 1 is a step-down chopper circuit. The C electric load 32 is the A induction coil 11L and the A electric load 1 in FIG.
It can be considered that the two are integrated. Therefore,
This example operates in the same manner as in FIG. 2 except that the part corresponding to the A induction coil 11L can be omitted. At this time, even when an induction coil is required as shown in FIG. 2, a small capacity according to the electric load of the circuit group is sufficient, and the size and weight can be reduced.

As in the present embodiment, a power control circuit and an electric load are paired to form one circuit group, and several circuit groups are connected in parallel to the main battery 1 so that the power supply of each circuit group can be reduced. Since the main battery 1 is used in common, a separate system battery is not required.

In the chopper circuit, the current flowing through the load can be increased or decreased by changing the conduction ratio, which is the rate of switching of the switching element. If the disconnection state is maintained, the power supply to the load can be stopped. That is, it is possible to individually start and stop the electric loads and perform the variable capacity operation for each circuit group.

Further, when a plurality of D electric loads 42 are connected in parallel as shown in FIG.
By starting and stopping the D electric load 42, the D electric load 42 can be simultaneously started and stopped for each circuit group.
It is also possible to start and stop independently by the load switch 42S individually connected to the power supply. If the D electric load 42 has the D load control command means 42C, it is also possible to individually perform the variable capacity operation. Further, according to the present embodiment, since both the power control circuit and the electric load can be of a rating and capacity according to the application, the optimization design is easy. For example, the rated power supply voltage and capacity of motors with different load capacities, such as motors for air conditioners, motors for wipers, and motors for power windows, can be set separately according to the application. It is possible to design according to the electrical load. That is,
It is possible to easily improve the efficiency of a single device, or to easily design the device in consideration of the external dimensions.

FIG. 6 shows an example in which load switching means 5 is added to two circuit groups. Here, FIG.
Has failed, the load switching means 5 is operated to supply the output of the F power control circuit to the E electric load 52 when the E electric load 52 is used with priority over the F electric load 62. ing.

As described above, as long as the capacity of the power control circuit and the capacity of the electric load are common in a plurality of circuit groups, they can be used as backup means. Since the chopper circuit has a bridge configuration, the inverter circuit can be considered in the same manner as in the present embodiment.

In FIG. 1, the power changing device 2 for the traveling motor and the power control circuits (11, 21,...) Are supplied with power from a single main battery 1. That is, since the cooling devices 4 for the heating elements such as semiconductors constituting the respective components can be shared, the devices can be simplified and the size and weight can be reduced. Further, the connection wiring to the main battery 1 is also made by the power changing device 2 for the traveling motor and the power control circuit (11, 21).
..) Can be shared, which is effective not only in simplifying and reducing the size and weight of the device, but also in terms of handling safety against high voltage of the main battery 1.

When a heating element of an electric load can be installed in the cooling device 4, the device can be simplified and reduced in size and weight by doing so.

[0026]

According to the present invention, the power supply portion of the auxiliary equipment can be reduced in size and weight, and the power supply to the auxiliary equipment which is not used is stopped, so that the power consumption of the battery is reduced.
This has the effect of extending the mileage. In addition, since high-voltage wiring is concentrated in the power converter for a traveling motor, there is an effect that safety design is facilitated.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a power control device for an electric vehicle, showing a configuration of the present embodiment.

FIG. 2 is a diagram showing an example of a case where the power control circuit is a step-down chopper circuit.

FIG. 3 is a diagram illustrating an example in which the power control circuit is a boost chopper circuit.

FIG. 4 is a circuit diagram showing an example in which an electric load has an electromagnetic induction effect.

FIG. 5 is a circuit diagram showing an example in which a plurality of electric loads are connected.

FIG. 6 is a circuit diagram showing an example of a circuit group having a load switching circuit.

[Description of Signs] 1 ... Main battery, 2 ... Power converter for traveling motor, 3 ...
Traveling electric motor, 4 ... cooling device, 5 ... load switching means, 11 ...
A power control circuit, 11L A induction coil, 12 A electric load, 13 A control command means, 14 A switching element, 15 free wheel diode.

Claims (5)

[Claims] 1. A high-voltage main battery and a power control circuit for converting an output voltage of the main battery into a required voltage and directly supplying and driving the connected electric load. Power control device for electric vehicles. 2. A power converter according to claim 1, wherein one or both of a heating element constituting said power control circuit and a heating element included in said electric load are provided. An electric power control device for an electric vehicle, comprising a single cooling device for simultaneously cooling. 3. The electric load according to claim 1 or 2,
An electric power control device for an electric vehicle, wherein the power control circuit is provided as one or more circuit groups, and a power control circuit is provided for each of the circuit groups. 4. An electric vehicle according to claim 3, further comprising a power control circuit for variably controlling or stopping an output in accordance with an amount of power required by said electric load connected to said circuit group. Power control device. 5. The power control for driving the circuit group using the electric load as an induction coil when the connected electric load has an electromagnetic inductive property among the circuit groups according to claim 3 or 4. A power control device for an electric vehicle, comprising a circuit.