JPH0284003A - Power system for electric vehicle - Google Patents

Abstract

PURPOSE:To continue operation with no trouble by connecting two controllers alternatively with a motor through first and second switchable contactors and switching the controller for the motor according to a predetermined timer sequence. CONSTITUTION:Any one of two controllers 2, 3 is connected alternatively with automobile drive motors 15, 16 by switching first and second contactors 11, 12, 13. 14. Switching of the controllers 2, 3 is carried out such that one controller 2(3) is stopped at first according to a predetermined timer sequence and the transient motor current is damped sufficiently then contactors 11, 12(13, 14) corresponding to the stopped controller 2(3) are opened and the contactors 13, 14(11, 12) are closed thereafter the other controller 3(2) is operated. By such arrangement, an automobile can be run continuously with no trouble.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric vehicle, and more particularly to a power system comprising an electric motor, a control device, etc. of an electric vehicle.

[Conventional technology]

As is well known, electric vehicles are driven by power systems such as batteries, electric motors, and control devices. When performing speed control, the control device usually changes the current flow rate of the electric motor according to the amount of depression of the accelerator pedal. Published on September 25th]
As described on pages 205 to 207 of , the conductivity of the armature or field of a DC motor is controlled by a semiconductor chopper such as a thyristor.

This type of electric vehicle is still inferior to regular engine-type vehicles in terms of charging range, practicality, economy, etc.
Because there is no exhaust gas and low noise.

For example, it is used as a means of transportation for special purposes, such as places where exhaust gas poses a problem, places with strict environmental cleanliness conditions, and facilities.

[Problem to be solved by the invention]

By the way, some of the uses for FT electric vehicles include:

For example, there are some vehicles, such as relay vehicles and escort vehicles for land road races, whose mission is to prevent them from stopping due to breakdowns or the like during use. For electric vehicles that require such high reliability, if a failure occurs in a system that is the heart of the vehicle, such as a control device, it will be impossible to continue driving, so countermeasures are especially necessary. It is. As a countermeasure, two switchable control devices are installed, and in the unlikely event that the control device currently in use should fail while driving, a contactor can be used to switch the remaining control device to another one. A switching method is proposed.

However, if such a dual system control device is switched without any consideration, the motor current (
Because the field current (field current, etc.) is not sufficiently attenuated, arc interruption occurs on the switching contactor's contact opening side, and due to welding, the contactors of each $11 control device connect at the same time.
Malfunctions or problems that cause the vehicle to stop running may occur.

Note that conventional motor control devices include, for example,
As disclosed in Publication No. 205556, there are some devices that switch to manual operation when the control current exceeds a specified value, but sufficient consideration must be given to switching the electric vehicle control device and making the switch smoothly. There was nothing that did that.

The present invention has been made in view of the above points, and its purpose is to install a dual system control device so that even if one control device fails, the remaining control devices can be connected smoothly. The purpose of the present invention is to provide a highly reliable electric vehicle that can be switched over and continued to be driven without any problems.

[Means to solve the problem]

The present invention has been made to achieve the above objects.

It has one electric motor that drives an electric vehicle and two control devices that control the electric motor.

The two control devices are connected to a switchable first control device. When alternatively connecting to the electric motor via a second contactor and switching the control device to the electric motor,
After stopping one of the control devices and sufficiently attenuating the motor current during the switching transition, one of the contactors corresponding to the stopped control device is opened, and then,
After closing the other contactor to be switched and connected,
A timer sequence is set to activate the other control device to which the switching connection is made.

[Effect]

According to the present invention having such a configuration, the first switch for switching
．． By switching the second contactor.

One of the two control devices is selectively connected to an electric motor for driving the vehicle.

In such a switching of the control devices, one of the control devices to be stopped is first stopped according to a predetermined timer sequence, and the motor current (field current, etc.) during the switching transition is sufficiently attenuated. After opening the contactor corresponding to the stopped control device and then closing the contactor to be switched and connected, the other control device to be switched and connected is activated.

In addition, in the present invention, as described above, the contactor that opens the contact at the time of switching is operated after the control device to be stopped is stopped and the field current of the a-motor is sufficiently attenuated. Arc interruption does not occur, and problems such as contactors being welded due to arc interruption and two control devices being connected at the same time can be prevented. Therefore, of course when switching between two control devices during normal operation, one
Even if a failure occurs in one control device and the use is switched to the remaining control device, by following the above-mentioned predetermined time sequence, the arc interruption phenomenon will be eliminated during the switching transition, ensuring smooth switching and continuing to disrupt vehicle operation. You can continue without any problems.

〔Example〕 An embodiment of the present invention will be described based on the drawings.

1 is a main battery, 2 and 3 are a control device, 10 is a switching device, 15
is the armature of a series-wound type motor (DC motor).

16 is a field coil, and 37 is an accelerator. In addition.

The electric motor 15 does not need to be a direct winding type, and may be of any other type, such as a split type, a belly type, or a separately excited type.

The control devices 2 and 3 have a main battery 1 and an armature 15. It is connected in parallel to the field coil 161s1ff, and the first control table [2 is the open/close switch 4. Freewheel diode 5. The second control device 3 is composed of a thyristor chopper 6, an open/close switch 7, a freewheel diode 8. It is composed of a thyristor chopper 9.

When the first control device 2 receives an operation command signal C1 of a timer sequence circuit 38, which will be described later, the first control device 2 switches the σ close switch 4.
is closed 5 Furthermore, when the second control device 3 similarly inputs the operation command signal Cz, the opening/closing switch 7 is closed, and each chopper 9 performs a chopper operation according to the amount of depression of the accelerator 36 to close the motor circuit. variably controls the conduction rate. Further, in each of the control tables W2 and W2, a starting sequence is set in which when the respective actuation signals of C1 and Cz are inputted, the chopper 6.9 is activated after waiting for a time constant Tc.

Moreover, when each of the Cx and Cz signals turns off, the chopper 6
．． A stop sequence is set in which switches 4 and 7 are opened after switch 9 is deactivated.

The switching device 10 has a first switching device. Corresponding to the second control device 2, 3, a first contactor 11.12 and a second contactor i
3.14. First contactor 11.12
The switch 41, the armature 15, the field coil 16. The second contactor 13.14 is connected in series with the chopper 6, and the switch 7, the armature 15. Field coil 16. It is connected in series with the chopper 9. In addition, these 1st. Second
The contactors are in parallel relationship. The first contactor 11.12 and the second contactor 13.14 are also controlled by the contactor coil 17.18 of the timer sequence circuit 38.

Next, the configuration and operation of the timer sequence circuit 38 will be explained in conjunction with the aforementioned control devices 2, 3, switching device 10, etc.
This will be explained with reference to the time chart shown in the figure.

The timer sequence circuit 38 includes a key switch 23, a battery 24 . It has an operation switch 25 for switching, and the first control device 2 and the first switching contactor 11.1 described above.
2 (relay coil 34. relay contact 35. timer 27. resistor 2)
9. Transistor 30. Relay coil 32. relay contact 21° contactor coil 18, etc.) and the second control device 3
and a second timer sequence system (relay coil 36, relay contact 37, timer 26, resistor 28, transistor 3) that controls the operation of the second switching contactors 13 and 14.
1. Relay coil 33. Relay contact 19. contactor coil 17, etc.).

After the key switch 23 is turned on, the operation switch 25
When it is turned to a, the relay coil 34 is energized and the contact 35 is closed. Further, the timer 27 outputs the signal with a delay of a certain time Tl. As a result of this timer output, an actuation signal C1 as shown in FIG. 2 is input to the control device 2 via the contact 35.

In addition, when the transistor 30 is turned on via the resistor 29 and the relay coil 32 is energized, the contact 21 is turned on, the contactor coil 18 is energized, and the switching contactors 11 and 12 are turned on (closed). Switching contactor 11.12 of control device 1 and switch 4 of control device 2 are closed, and control device 2 and armature 15.1 are closed. The field coil 16 is connected. Then, after the contactors 11 and 12 and the switch 4 are closed, the chopper 4 is activated after waiting for the time constant Tc according to the startup sequence in the control device 2, and the motor current IMI according to the accelerator 37 flows, controlling the rotation of the motor. will be held.

In this way, since the motor current IMI flows after the contactors 11, 12 and the switch 4 are closed, the generation of rush current can be prevented.

Next, when the operating switch 25 is turned toward b, the relay coil 34 is de-energized and the contacts 35 are turned off, while the relay coil 36 is energized and the contacts 37 are turned on. Contact 3
5 is turned off.

The activation signal Cs to the control device 2 is interrupted. When the CI is shut off, control table [2] first stops the operation of the chopper 6 and opens the switch 4 according to a predetermined stop sequence. When the chopper 6 stops operating, the decay current of the armature 15 and the field coil 16 flows through the armature, the field coil, and the flywheel diode 5flIl, so the switch 4
There will be no arcing on the sides. Thereafter, the output of the timer circuit 27 is cut off with a delay of Tz, the transistor 30 is turned off, the contactor coil 18 is therefore no longer energized, and the first switching contactor 11.12 is opened.

Here, the time Tz, that is, the time from when the switch 25 is turned to the b side until the switching contactor 11, 12 opens, is:
The first switching contactor 11.12 opens without arc interruption, since the length is set to be sufficient for the damping currents of the armature 15 and the field coil 16 to decay sufficiently.

Thereafter, the timer circuit 26 on the second timer sequence system side outputs an output with a delay of time Ts, and the activation signal C2 is input to the control device 3 via the contact 37 due to this timer output. Furthermore, by turning on the transistor 31,
Relay coil 33 is turned on, contact 19 is turned on, contactor coil 17 is energized, and second switching contactor 13.1 is turned on.
4 turns on. In this way, the second switching contactor 13.14 and the switch 7 of the control device 3 are closed, so that
Control device 3 and armature 15. Field coil 16 is connected. In this case as well, after the contactors 13 and 14 and the switch 7 are closed, the chopper 9 is activated after waiting the time constant Tc according to the activation sequence in the control device 3, and the accelerator 37 is activated.
A motor current of IHz flows in accordance with the current, and the rotation of the motor is controlled.

Then, since the motor current Isz flows after the contactors 11 and 12 and the switch 7 are closed, no rush current flows.

In this embodiment, the contactor coils 17, 18 are connected to relay contacts 19, 20, 21 .
22 constitutes an inhibit configuration. In addition, the wires of the relay coils 32 and 33 are connected to the key switch 2 so that the timer circuits 26 and 27 operate even if the key is turned off while driving.
It is taken directly from the 12V battery 24 connected through the 3. The chopper 6.9 is not limited to a thyristor, and other transistors may be used.

According to this embodiment, the contact a of the operation switch 25.

By switching b, the switching contactor 11 on the off side
．． Since the control devices 2 and 3 can be switched without arc interruption occurring at 12 or 13.14, it is possible to eliminate the problem of simultaneous connection of the control devices 2 and 3 due to contactor welding. Even if one of the control devices 2 and 3 fails, it is possible to switch the control device to the normal one and continue driving the electric vehicle smoothly, making it suitable for applications where stopping midway is not allowed. We can provide the most suitable electric vehicle. In addition, switch 4 of the control device that turns on at the time of switching (
or 9) and switching contactor 11°12 (or 13.
Since the startup sequence is set so that the chopper 6 (or 9) is activated after closing i4), rush current can be prevented.

In the case of a thyristor-type chopper, the rush current causes commutation failure, and in the case of a transistor-type chopper, the rush current exceeds the peak value of the current and causes destruction of the transistor.

〔Effect of the invention〕

As described above, according to the present invention, the dual system control device is switchably provided for the drive motor of an electric vehicle, and the control device can be switched smoothly without any trouble. , even if one of the control devices fails,
Normal operation can continue and the reliability of electric vehicles can be significantly improved.

[Brief explanation of the drawing]

Fig. 1 is a system configuration diagram showing one embodiment of the present invention;
The figure is a time chart showing its operating state. 1... Main battery, 2, 3... Control device, 10... Switching device.

Claims (1)

[Claims] 1. It has one electric motor that drives an electric vehicle, two control devices that control the electric motor, and the two control devices are provided with switchable first and second contactors. in the case where the control device is selectively connected to the electric motor via the electric motor and the control device is switched to the electric motor,
After stopping one of the control devices and sufficiently attenuating the motor current during the switching transition, one of the contactors corresponding to the stopped control device is opened, and then,
After closing the other contactor to be switched and connected,
A power system for an electric vehicle, characterized in that a timer sequence is set to operate the other control device to be switched and connected.