JPH0530606A - Brake and auxiliary drive for vehicle - Google Patents

Abstract

PURPOSE:To protect a resistor from being disconnected due to vibration of vehicle by controlling the operation of an inverter circuit based on the terminal voltage of cooler for the resistor. CONSTITUTION:A control means 7 controls the operation of an inverter circuit 2 based on the terminal voltage of a cooler 12 for a resistor and the temperature of the resistor 9. The control means 7 detects failure of the cooler 12 and interrupts the operation of the inverter circuit 2 upon failure of the cooler 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to vehicle braking and auxiliary drive systems, and more particularly to cooling a resistor for consuming excess power generated by an induction machine for vehicle braking and drive assist systems. When an abnormality occurs in the device, the operation of the inverter circuit is stopped to prevent the resistor from being cut off due to the vibration of the vehicle for a long time and the high temperature state of the resistor. Auxiliary drive device.

[0002]

2. Description of the Related Art Conventionally, an induction machine is attached to a power line of a vehicle, and when the vehicle is braked, the AC power generated by the induction machine is converted into DC power and supplied to a battery, and at the same time when the vehicle is accelerated to start, There has been proposed an electric braking and auxiliary drive device configured to take out stored electric energy, convert it into AC power, and supply it to the induction machine to assist the wheel drive (for example, Japanese Patent Laid-Open Publication No. Sho 6-62).
3-206101 gazette).

FIG. 2 is a circuit block diagram showing an example of a conventional vehicle braking and auxiliary drive system.

In FIG. 2, reference numeral 1 is an induction machine attached to a power line and used as a generator or an electric motor. The induction machine 1 is used as a generator when braking the vehicle. In this case, the electric power generated by the induction machine 1 is converted into direct current by the inverter circuit 2. Here, the capacitor 3 is for smoothing. The electric power converted into this direct current is
For example, 96 by the voltage conversion circuit 20 including the step-down chopper 13, the backflow prevention diode 15, and the coil 14.
It is converted into VDC and stored in the battery 10. As a result, regenerative braking is performed when the vehicle is being braked. The induction machine 1 is used as an electric motor when the vehicle is accelerated or started. In this case, the electric power stored in the battery 10 is taken out and boosted by the voltage conversion circuit 20. The boosted DC power is converted into AC power by the inverter circuit 2 and input to the induction machine 1 to assist driving of accelerating or starting the vehicle. A photo coupler 4 is provided in the inverter circuit 2, and the photo coupler 4 controls the operation and stop of the inverter circuit 2.

The electric power stored in the battery 10 is D
It is converted into, for example, 24 VDC by the C-DC converter 11, and is supplied to various vehicle electrical components.

A resistor 9 is connected in parallel with the capacitor 3 via a semiconductor switch circuit 21. The resistor 9 dissipates the excess electric energy as heat energy when it is difficult to regenerate all the electric energy from the induction machine 1 to the battery 10 due to a temporary large brake torque. belongs to. The switch circuit 21 is controlled by a control circuit (not shown), and this control circuit is normally the switch circuit 2
1 is kept in the OFF state, and the DC terminal voltage of the inverter circuit 2 is monitored, and the switch circuit 21 is controlled so that the switch circuit 21 is turned ON when the terminal voltage exceeds a predetermined value.

A cooling fan 1 is provided near the resistor 9.
2a and a cooling fan motor 12 for driving the same 2a are provided, and the fan motor 12 has the DC-DC
24 VDC power from the converter 11 is supplied through the 24V power supply line 16.

The resistor 9 has a resistor temperature sensor 8
Is attached. The signal from the temperature sensor 8 is input to the control device 7. 24 VDC power from the DC-DC converter 11 is supplied to the control device 7 through the power supply line 16 and the distributor 17, and a hardware configuration of the control device 7 is a microcomputer. It is composed of an interface circuit such as an A / D converter and a D / A converter. The output of the controller 7 is connected to normally closed relay circuits 5 and 6 provided between the light emitting diode of the photocoupler 4 in the inverter circuit 2 and the 12VDC power source for driving the light emitting diode. .. The controller 7 monitors the temperature of the resistor 9 based on the input from the temperature sensor 8, and when an abnormal rise in the temperature of the resistor 9 is detected,
The normally closed relay circuits 5 and 6 are turned off so that the light emitting diode of the photocoupler 4 is turned off. Thus, when the temperature of the resistor 9 abnormally rises, the operation of the inverter circuit 2 is stopped to prevent the abnormal temperature rise of the resistor 9.

[0009]

However, in the conventional vehicle braking and auxiliary acceleration device as described above, the operation of the inverter circuit 2 is stopped only when the temperature of the resistor 9 becomes abnormally high as described above. Because I was trying to
The cooling fan motor 12 fails and the cooling fan 12a
Does not operate, even if the abnormal temperature rise of the resistor 9 is detected and the operation of the inverter circuit 2 is stopped, the cooling fan does not operate and the abnormal high temperature state of the resistor 9 continues for a long time. In the meantime, there is a possibility that the resistor 9 may be disconnected due to vibration of the vehicle or the like.

The present invention has been made in view of the above-mentioned problems of the prior art. When the cooling device for cooling the resistor for dissipating the excess electric energy fails, the temperature of the resistor is reduced. It is an object of the present invention to provide a vehicle braking and auxiliary drive device that prevents disconnection of a resistor or the like due to a long-term abnormal rise and vibration of the vehicle during that period.

[0011]

A cooling device for a vehicle braking and auxiliary drive induction machine according to the present invention for achieving the above object is produced by an induction machine mounted on a power line and the induction machine. A battery that stores electric energy, and converts the AC power generated by the induction machine into DC power and supplies the DC power to the battery, and also converts the DC power from the battery into AC power of a desired frequency to the induction machine. Based on an inverter circuit to be supplied, a resistor connected to both ends of the battery through switching means, a cooling device for cooling the resistor, a terminal voltage of the cooling device and a temperature of the resistor. And a control means for controlling the operation of the inverter circuit.

[0012]

According to the above means, there is provided the control means for controlling the operation of the inverter circuit based on the terminal voltage of the cooling device for cooling the resistor, and the control means is provided for the failure of the cooling device. The presence or absence of the above condition is detected, and the operation of the inverter circuit is stopped when the cooling device fails and when the temperature of the resistor exceeds a predetermined value.

[0013]

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

FIG. 1 is a circuit block diagram showing a vehicle braking and auxiliary drive system according to an embodiment of the present invention. This Figure 1
The elements common to the elements of the circuit of the conventional example shown in FIG. 2 are given the same reference numerals as those in FIG. 2 and their explanations are omitted.

In the device shown in FIG. 1, a transistor switch 18 is connected between the light emitting diode of the photocoupler 4 in the inverter circuit 2 and the 12V power source for driving the light emitting diode. The output from the control device 7 is normally controlled to be in a conductive state. On the other hand, the terminal voltage of the fan motor 12 is input to the control device 7. The control device 7 thereby monitors the terminal voltage of the fan motor 12, and when this terminal voltage becomes lower than a predetermined value, determines that an abnormality such as a failure has occurred in the fan motor 12, and turns off the transistor switch 18. .. As a result, the light emitting diode of the photocoupler 4 is turned off, and the operation of the inverter circuit 2 is stopped.

Next, as another embodiment, one corresponding to FIG. 1 is shown in FIG. 3 and one corresponding to FIG. 2 is shown in FIG. In FIGS. 3 and 4, portions common to FIGS. 1 and 2 are denoted by the same reference numerals.

The embodiment of FIG. 3 is a relay 5 of the embodiment of FIG.
Is a bimetal type temperature switch 5 ', which is provided in a case (not shown) of the resistor 9 and is set to be turned off when the temperature of the resistor exceeds a predetermined value. The terminal voltage of the fan motor 12 is directly connected to the normally closed relay circuit 6 via the distributor 17, and the light emitting diode of the photocoupler 4 and the 12VDC power source for driving the light emitting diode are connected via the relay circuit 6. There is.

Also in the embodiment shown in FIG. 4, the terminal voltage of the normally closed bimetal type temperature switch 5'and the fan motor 12 is directly connected to the normally closed relay circuit 6 through the distributor 17, and the bimetal switch 5'is connected. And the normally closed relay 6 are connected in series to connect the light emitting diode 4 of the photocoupler and the 12VDC power source for driving the light emitting diode 4.

Therefore, in the embodiments of FIGS. 3 and 4, the bimetal switch 5'is opened due to an abnormal rise in the temperature of the resistor and the photocoupler emits light, as in the examples shown in FIGS. 1 and 2, respectively. The diode is turned off, and the light emitting diode of the photocoupler is turned off and the inverter is stopped even when the cooling fan motor 12 fails and power is not applied to the fan motor.

Therefore, in these embodiments, when the fan motor 12 fails and the terminal voltage of the fan motor 12 drops, the control device 7 detects this and stops the operation of the inverter circuit 2. Therefore, since the cooling fan motor 12 is out of order and the resistor 9 is not cooled at a high temperature as in the conventional case, it is possible to avoid the inconvenience that the resistor 9 is disconnected due to the vibration of the vehicle. become.

[0021]

As described above, according to the present invention, the control means for controlling the operation of the inverter circuit based on the terminal voltage of the cooling device for cooling the resistor and the temperature of the resistor is provided. Therefore, when the cooling device fails, the operation of the inverter circuit can be stopped. Therefore, as in the conventional case, even if the cooling device fails, the operation of the inverter circuit is continued and the operation of the inverter circuit is stopped only when an abnormally high temperature of the resistor is detected. Even if the inverter circuit is stopped due to a high temperature, the abnormal high temperature of the resistor continues for a relatively long time, and during that period it is possible to avoid inconveniences such as the resistor breaking due to vehicle vibration and the like. ..

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an overall configuration of a first embodiment of the present invention.

FIG. 2 is a circuit block diagram showing a conventional vehicle braking and auxiliary drive device.

FIG. 3 is a circuit block diagram showing a second embodiment of the present invention.

FIG. 4 is a circuit block diagram showing a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Induction machine 2 Inverter circuit 4 Photocoupler 5, 6 Normally closed relay circuit 7 Control device 8 Temperature sensor 9 Resistor 10 Battery 12a Cooling fan 12 Cooling fan motor 18 Transistor switch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayuki Suzuki, 1-1, Hinodai, Hino City, Tokyo Hino Motors Co., Ltd. Hino Factory

Claims (1)

Claim: What is claimed is: 1. An induction machine attached to a power line, a battery for storing electric energy generated by the induction machine, and AC power generated by the induction machine, converted to DC power. An inverter circuit that supplies the battery and converts the DC power from the battery to AC power of a desired frequency and supplies the AC power to the induction machine; and a resistor connected to both ends of the battery via switching means, A braking device for a vehicle, comprising: a cooling device for cooling the resistor; and a control means for controlling the operation of the inverter circuit based on the terminal voltage of the cooling device and the temperature of the resistor. Auxiliary drive.