JPH0532961B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is for protecting internal elements and circuits from damage when the voltage of the gate control power supply of a thyristor circuit used in a protection device for an electric vehicle running control device decreases. It concerns the means of

[Conventional technology]

FIG. 3 is a partial block diagram of a conventional protection device for an electric vehicle running control device using a thyristor circuit. In the figure, 1 is an overhead wire, 2 is a current collector in contact with the overhead wire 1, 3 is a filter reactor, and 4 is a filter capacitor. The filter reactor 3 and the filter capacitor 4 constitute a filter circuit 4a. . Moreover, a circuit breaker 10, a filter reactor 3, and a filter capacitor 4, which will be described later, are connected in series between the current collector 2 and the ground.

5 is a thyristor circuit directly connected to the filter capacitor 4, 6 is a load connected to this thyristor circuit 5, 7 is a gate control circuit for controlling the thyristor circuit 5, and 8 is this gate control circuit 7.
A control power source 9 is a voltage drop detector for detecting a voltage drop in the control power source 8 . The circuit breaker 10 described above is a circuit breaker for protecting the thyristor circuit 5 and for turning on/off the power from the current collector 2, and is activated by the operation command, the detection output of this voltage drop detector 9, or other protection output. On/off operation is controlled.

Next, the operation will be explained. Thyristor circuit 5
Electric power is supplied from the overhead wire 1 through the filter circuit 4a. The power smoothed through the filter circuit 4a is converted from DC to DC or from DC to AC in a thyristor circuit 5, and is applied to a load 6 such as a motor or auxiliary equipment.

A gate control circuit 7 for controlling the thyristor circuit 5 controls the gate of the thyristor 5a of the thyristor circuit 5 in response to a command from an electric vehicle driver's cab (not shown) or the electrical state of the load 6. A signal is output and input to the thyristor circuit 5. Normally, the circuit breaker 10 is kept in the on state while the thyristor circuit 5 is in operation, but for example, if the voltage of the control power source 8 drops to a voltage below which can guarantee the operation of the thyristor circuit 5, The circuit breaker 10 is turned off by the detection output of the voltage drop detector 9, and the thyristor circuit 5 is protected.

FIG. 4 is an explanatory diagram showing the operating state of the circuit breaker 10 and the state of the output of the gate control circuit 7 when the voltage of the control power supply 8 decreases. That is, when the voltage level of the control power source 8 becomes lower than the detection level (threshold value) of the voltage drop detector 9, the circuit breaker 10 is turned off, and when the voltage of the control power source 8 further decreases, an erroneous gate pulse is generated from the gate control circuit 7. Pn was applied to the thyristor circuit 5.

[Problem that the invention seeks to solve]

Since the conventional protection device for the electric vehicle running control device is configured as described above, when the control power source 8 of the gate control circuit 7 falls below the reference voltage that guarantees the operation of the thyristor circuit 5 while the electric vehicle is operating, There is a possibility that an erroneous gate pulse Pn is applied to the thyristor circuit 5, and the thyristor circuit 5 directly connected to the filter capacitor 4 may
may be energized by residual charge. In this case, there was a problem that a failure occurred in the thyristor 5a and the built-in circuit in the thyristor circuit 5.

This invention was made to solve the above-mentioned problems, and even if an erroneous gate pulse is applied to the thyristor circuit 5 when the voltage of the control power supply 8 of the gate control circuit 7 drops, the thyristor circuit 5 is The object of the present invention is to obtain a protection device for an electric vehicle running control device that can be protected.

[Means for solving problems]

A protection device for an electric vehicle running control device according to the present invention is a protection device for an electric vehicle running control device having a filter capacitor discharge circuit 12a, a gate circuit 11, and a voltage drop detector 9, and the electric vehicle has the following features:
It is controlled by a filter circuit 4a composed of a filter reactor 3 connected to a current collector 2 via a circuit breaker 10 and a filter capacitor 4, and a gate control circuit 7 driven by a control power source 8. The filter capacitor discharge circuit 12a includes a thyristor circuit 5 and a load 6.
Connected in parallel with filter capacitor 4, resistor 1
2, and a filter capacitor charge discharge thyristor 13 connected in series to the resistor 12,
The filter capacitor charge discharging thyristor 13 is turned on and off by the gate circuit 11, and the voltage drop detector 9 detects that the voltage of the control power supply 8 has fallen below the guaranteed operation value of the thyristor circuit 5. The circuit breaker 10 is opened, and the filter capacitor charge discharging thyristor 13 is fired for the gate circuit 11 to discharge the residual charge in the filter capacitor 4.

[Effect]

The protection device for an electric vehicle running control device according to the present invention operates the filter capacitor discharge circuit 12a by detecting the voltage drop of the control power source 8, and the residual charge in the filter capacitor 4 is discharged by this operation. Even if, for example, the gate pulse occurs when the voltage of the control power source 8 drops, the filter capacitor 4 is connected to the thyristor circuit 5.
No current flows from the thyristor circuit 5, and the elements and circuits within the thyristor circuit 5 are protected.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In Figure 1, 1 is an overhead wire, 2 is a current collector, and 3
4 is a filter reactor, and 4 is a filter capacitor. The filter reactor 3 and the filter capacitor 4 constitute a filter circuit 4a. 5 is a thyristor circuit directly connected to this filter capacitor 4, 12a is connected in parallel to this filter capacitor 4, and also includes a resistor 12 and a thyristor 13 for discharging the charge of the filter capacitor.
A filter capacitor discharge circuit consisting of a series body of
6 is a load such as a motor connected to this thyristor circuit 5, 7 is a gate control circuit for controlling this thyristor circuit 5, and 8 is this gate control circuit 7.
9 is a voltage drop detector for detecting a voltage drop in the control power source 8; 10 is the current collector 2 and the filter reactor 3;
This circuit breaker is used to protect the thyristor circuit 5 connected between the thyristor circuit 5 and to turn on/off the power from the current collector 2, and is used to receive operation commands, control signals from this voltage drop detector 9, or other protection. The signal turns it on.
Off operation is controlled. Reference numeral 11 denotes a gate circuit for receiving the output of the voltage drop detector 9 and igniting the filter capacitor charge discharging thyristor 13.

Next, the operation will be explained. When the voltage of the control power source 8 of the gate control circuit 7 drops below the voltage that can guarantee normal gate circuit operation during operation of the electric vehicle, the voltage drop detector 9 operates and its detection output opens the circuit breaker 10. , gate circuit 11
Give a gate pulse output command signal to. As a result, the residual charge in the filter capacitor 4 is removed from the filter capacitor charge discharging thyristor 13 and the resistor 12.
The filter capacitor 4 is discharged with a time constant determined by
The voltage of becomes zero. Now, even if the voltage of the control power supply 8 further decreases and the gate control circuit 7 applies an erroneous gate pulse to the thyristor circuit 5, the voltage of the filter capacitor 4 has already decreased to zero, so the thyristor circuit 5 No current flows, and damage and failure of the circuits and thyristor elements in the thyristor circuit 5 can be prevented.

FIG. 2 shows the voltage of the filter capacitor 4 and the operating state of the circuit breaker 10 when the voltage of the control power supply 8 decreases. That is, when the voltage level of the control power source 8 becomes lower than the detection level (threshold value) of the voltage drop detector 9, the circuit breaker 10 is turned off, and at the time the circuit breaker 10 is turned off, the filter capacitor 4 is turned off. The voltage between the terminals of will also be zero. Therefore, even if an erroneous pulse Pn is generated from the gate control circuit 7, the thyristor circuit 5 is not energized and the thyristor in the thyristor circuit 5 is not damaged.

In addition, in the above embodiment, the same effect can be obtained even if a separate protection thyristor is provided or a thyristor (not shown) for suppressing overvoltage of the filter capacitor voltage built into the conventional thyristor circuit is used. The effect of this can be obtained.

Furthermore, although all of the above embodiments have been described using thyristors as circuit elements, it goes without saying that similar effects can be obtained by using other power conversion elements.

〔Effect of the invention〕

As described above, the present invention is a protection device for an electric vehicle running control device having a filter capacitor discharge circuit 12a, a gate circuit 11, and a voltage drop detector 9. A filter circuit 4a comprising a filter reactor 3 and a filter capacitor 4 connected to the current collector 2, and a thyristor circuit 5 controlled by a gate control circuit 7 driven by a control power source 8.
and a load 6, and the filter capacitor discharge circuit 12a has a filter capacitor 4
The filter capacitor charge discharging thyristor 13 is connected in parallel to the resistor 12 and is connected in series to the resistor 12. The filter capacitor charge discharging thyristor 13 is turned on and off by a gate circuit 11, Voltage drop detector 9
detects that the voltage of the control power source 8 has fallen below the guaranteed operation value of the thyristor circuit 5, opens the circuit breaker 10, and ignites the filter capacitor charge discharging thyristor 13 for the gate circuit 11. Since the residual charge in the filter capacitor 4 is discharged by the thyristor circuit 5, the thyristor elements and circuits in the thyristor circuit 5 can be safely protected even if an erroneous pulse is generated from the gate control circuit 7 when the control power supply voltage drops. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a protection device for an electric vehicle running control device according to an embodiment of the present invention, FIG. 2 is an operation explanatory diagram showing the operation of the block circuit of FIG. 1, and FIG. FIG. 4 is a block circuit diagram showing the protection device for the traveling control device. FIG. 4 is an operation explanatory diagram showing the operation of the block circuit shown in FIG. 3. 4 is a filter capacitor, 5 is a thyristor circuit, 7 is a gate control circuit, 8 is a control power supply, 9 is a voltage drop detector, 11 is a gate circuit, 12a is a filter capacitor discharge circuit, 12 is a resistor, 13 is a filter capacitor charge discharge It is a thyristor for
In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. A protection device for an electric vehicle running control device having a filter capacitor discharge circuit 12a, a gate circuit 11, and a voltage drop detector 9, which A filter circuit 4a composed of a filter reactor 3 and a filter capacitor 4 connected to the electric appliance 2, a thyristor circuit 5 controlled by a gate control circuit 7 driven by a control power source 8, and a load 6. The filter capacitor discharge circuit 12a is connected in parallel to the filter capacitor 4, and has a resistor 12,
The filter capacitor charge discharge thyristor 13 is connected in series to a resistor 12, and the filter capacitor charge discharge thyristor 13 is turned on and off by a gate circuit 11. The voltage drop detector 9 is connected to a control power supply 8. The circuit breaker 10 is opened upon detecting that the voltage of the thyristor circuit 5 has become lower than the guaranteed operation value of the thyristor circuit 5, and the gate circuit 1 is opened.
1, the filter capacitor charge discharging thyristor 13 is ignited to discharge the residual charge in the filter capacitor 4. Protection device for electric vehicle running control equipment.