JPH03107301A - Controller for electric vehicle - Google Patents

Abstract

PURPOSE:To exhibit function as an overvoltage suppressing thyrister positively by turning a gate turn OFF thyrister ON upon detection of overvoltage while turning the gate turn OFF thyrister OFF upon detection of droppage of input voltage below a predetermined level. CONSTITUTION:Power to be fed from a DC stringing 1 through a pantograph 2 is inverted by means of an inverter 8 through a filter reactor 3 and a filter capacitor 7 and fed to an induction motor 9. When overvoltage appears at the output of a voltage detector 4, FF 12 is set by the output from an overvoltage detector 10 and a gate turn OFF thyristor 6 is turned ON through a gate pulse amplifier 15. When the output from the voltage detector 4 drops below a predetermined level, the FF 12 is reset by the output from a voltage drop detector 11 and the gate turn OFF thyristor 6 is turned OFF.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for an electric vehicle, and particularly to an electric vehicle control device equipped with a chopper device for absorbing regenerative power and suppressing overvoltage.

[Conventional technology]

As shown in Japanese Unexamined Patent Publication No. 135203/1983, there are conventional devices that use a chopper for controlling power generation and suppressing overvoltage, but when a gate turn-off thyristor is used as a thyristor for the chopper, The gate pulse sequence is not mentioned.

[Problem to be solved by the invention]

The above conventional technology uses a gate turn-off thyristor as a chopper thyristor for power generation control and overvoltage suppression.
When operating this as an overvoltage suppressing thyristor, no consideration has been given to the gate-off conditions after the gate is turned on. Conventionally, when an on-pulse of several tens to 100 μsec is applied like a thyristor, an off-pulse is generated immediately after the on-pulse period ends. Because of this, there was a risk that the function as an overvoltage suppressing thyristor would stop before the overvoltage was sufficiently suppressed. is normal).

An object of the present invention is to ensure that, when a gate turn-off thyristor chopper for power generation control and overvoltage suppression functions as an overvoltage suppression thyristor, the voltage drops reliably, regardless of the amount of energy of the power source that causes overvoltage. The object of the present invention is to provide a device that operates as an overvoltage thyristor.

[Means to solve the problem]

The above purpose is to fire the gate turn-off thyristor,
This is achieved by detecting that the power supply voltage has fallen below a predetermined value as a condition for extinguishing the arc.

[Effect]

Even if the speed at which the input voltage drops after firing the gate turn-off thyristor differs due to differences in the power of the power source that causes overvoltage, the gate turn-off thyristor continues firing until the input voltage falls below a predetermined value. Therefore, overvoltage can be suppressed reliably.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. In the figure, 1 is a DC overhead wire, 2 is a pantograph, 3 is a filter reactor, 4 is a voltage detector, 5 is a resistor for absorbing regenerative power and suppressing overvoltage, 6 is a chopper, 7 is a filter capacitor, 8 is an inverter, 9 is an induction motor for driving an electric vehicle, 10 is an overvoltage detector, and 11 is a voltage drop detector.

12 is a flip-flop, 13 is a regenerative power absorption chopper controller, 14 is an OR circuit, and 15 is a gate pulse amplifier. When the chopper 6 operates as an overvoltage suppressing thyristor, the gate pulse amplifier 15 is controlled by the output of the flip-flop 12. When the overvoltage detector 10 detects overvoltage based on the output of the voltage detector 4, the output becomes 11.
It's H11.

The output of the flip-flop 12 becomes H'' and the chopper 6
An on-pulse is given to the gate turn-off thyristor. - day, the output of flip-flop 12 is 11 H11
Then, an on-pulse is applied to the gate turn-off thyristor of the chopper 6 until the output of the voltage drop detector 11 becomes "IIH".

According to this embodiment, the only circuits that need to be added to obtain the effects of the present invention are the voltage drop detector 11 and the flip-flop 12.

〔Effect of the invention〕

According to the present invention, when the gate turn-off thyristor chopper for dynamic braking and overvoltage suppression is operated as an overvoltage suppression thyristor, even if the voltage drop rate varies depending on the power of the power source that causes overvoltage generation, the predetermined voltage can be reliably maintained. The function as an overvoltage suppressing thyristor can be maintained until the voltage falls below the voltage.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... DC overhead wire, 6... Chopper for regenerative power absorption and overvoltage suppression, 9... Main motor for driving electric vehicle, 10.
・Figure

Claims (1)

[Claims] 1. In a control device for an electric vehicle, which is supplied with power from a DC power supply and controls a main motor for driving an electric vehicle, and is equipped with a chopper device for absorbing regenerative power and suppressing overvoltage, a gate turn-off thyristor is used as the main thyristor for the chopper, When the gate turn-off thyristor is made to function as an overvoltage suppressing thyristor, the gate turn-off thyristor is turned on at the same time as overvoltage is detected, and then turned off when the input voltage of the control device is detected to be lower than a predetermined value. An electric vehicle control device characterized by: