JPH0755007B2 - Electric vehicle control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a current command value, which is a current supplied from an overhead wire via a pantograph and a switch to a DC electric motor for driving an electric vehicle in which a filter capacitor is connected in parallel. The present invention relates to a control device for an electric vehicle that controls the choppers so that they match.

[Technical background of the invention and its problems]

FIG. 5 shows a typical example of a main circuit configuration conventionally implemented as a control device for an electric vehicle of this type. This circuit configuration shows a connection state during power running when the DC series-wound motor 5 is controlled using the main chopper 8 and the field chopper 11.

In this circuit state, power is collected from the overhead wire P via the pantograph 1, and the collected direct current is a direct current composed of the line breaker 15, the filter reactor 3, the high speed circuit breaker 16, the armature 6 and the field 7. It flows to the rail R via the series winding motor 5, the main chopper 8, and the wheels 2. The breaker 15 and the high speed circuit breaker 16 will be collectively referred to as a switch.
A charging resistor 17 is connected in parallel to the high speed circuit breaker 16, and a filter capacitor 4 is connected to the electric motor 5 and the main chopper 8 so as to form a parallel shunt. A field permanent shunt resistor 9 and a field adjusting shunt consisting of a series circuit of a field shunt resistor 10 and a field chopper 11 are connected in parallel to the field 7. A freewheeling diode 12 is further connected to the electric motor 5 in parallel. A low voltage relay 14 is connected between the pantograph 1 and the wheel 2 via a resistor 13 for monitoring the current collecting voltage and detecting it when it falls below a predetermined value.

FIG. 6 shows an example of a device for controlling the electric current of the electric motor 5. The current limiting value ICO is input from the current limiting value transmitter 21 to the H side fixed contact of the changeover switch 22, a zero value is input to the L side fixed contact, and the output IC1 is output according to which side, H or L, is switched. = Output ICO or 0. When the start condition and the current reduction condition are both "H", the changeover switch 22 has an AND gate 3
It is switched to the H side via 0, and is switched to the L side in other cases. The output IC1 of the changeover switch 22 is input to the H-side fixed contact of the second changeover switch 24 as the signal IC2 via the first-order lag element 23. A zero value is input to the L-side fixed contact of the changeover switch 24. The changeover switch 24 is switched to the H side when the starting condition is "H", and is switched to the L side otherwise. The output signal of the changeover switch 24 is input to the constant current control device 25 as a target armature current command value IC. The actual current value IA of the electric motor 5 detected by the current detector 20 is negatively fed back to the constant current control device 25.
25 controls the conduction ratio α of the main chopper 8 via the gate amplifier 26 so that IA = IC.

FIG. 7 shows an example of the relationship among the start condition, the current reduction condition, and the current command value IC. It is shown that the rising and falling of the current command value IC change exponentially with the time constant T due to the first-order lag effect.

In the control device for an electric vehicle configured as described above, the low-voltage relay 14 operates when the collecting voltage decreases due to the disconnection of the pantograph 1, etc., and the operation output thereof causes the switch, that is, the high-speed circuit breaker 16 and the disconnection. Open the container 15.
When the collecting voltage is restored by reattachment of the pantograph 1, the low-voltage relay 14 also recovers, the breaker 15 is closed, the filter capacitor 4 is charged through the charging resistor 17, and the high speed circuit breaker 16 Then, the main chopper 8 and the field chopper 11 are operated.

According to this operation sequence, since the charging current is limited by the charging resistor 17 when the filter capacitor 4 is recharged, a sharp rise of the charging voltage of the filter capacitor 4 can be avoided. Further, normally, since the main chopper and the field chopper 11 are stopped by turning off the line breaker 15 and the high speed circuit breaker 16, inconvenience such as electric motor overcurrent does not occur when the filter capacitor 4 is recharged.

However, in the device of FIG.
When the pantograph is disconnected for such a short time that 14 cannot operate,
The re-attachment of the pantograph will be performed with the circuit breaker 15 and the high speed circuit breaker 16 closed.

FIG. 6 shows how the voltage of the filter capacitor 4 changes during disconnection and reattachment in that case. When the line is disconnected at point A, the capacitor voltage EC drops by x volts, and when re-attached at point B, it overshoots the voltage value before disconnection and rises by 2x volts, for example, based on the voltage value at point B. Cause During this time, the chopper 8 and the field chopper 11 continue to operate, but the current flowing through the electric motor 5 becomes excessive due to a sharp rise in the filter capacitor voltage, and the overcurrent protection device operates. In the extreme case, the devices such as the choppers 8 and 11 may be damaged.

Such inconvenience is caused by the low operating speed of the low voltage relay 14. However, even if the low-voltage relay 14 is replaced with a low-voltage detector having a high operating speed, for example, disconnection-low-voltage detector operation-high-speed circuit breaker 16 open circuit-break circuit 15 open circuit-re-connection-break circuit breaker. 15 ・ High-speed circuit breaker 16 A series of operation sequence of reclosing is required, and if disconnection occurs frequently, it not only shortens the contact life of the breaker 15 and high-speed circuit breaker 16, but also requires restarting. Acceleration performance of the train is deteriorated depending on time, and the frequent operation of the solenoid valve for turning on and off the disconnector 15 and the high-speed circuit breaker 16 causes deterioration of riding comfort due to noise and vibration.

[Object of the Invention]

The present invention has been made in order to eliminate the above-mentioned inconvenience, and avoids unnecessary overload protection operation and damage to the chopper device at the time of short-distance disconnection, and also makes sequence operation unnecessary. An object of the present invention is to provide a control device for the electric vehicle.

[Outline of Invention]

In order to achieve the above-mentioned object, the chopper is stopped without opening the switch due to the detection of a wire break, the current command value is set to zero, and after a constant delay time due to re-adhesion, the current command The feature is that the value is gradually increased from zero with a first-order lag.

Example of Invention

First, with reference to FIG. 3, an algorithm of the stop-restart operation at the time of wire break according to the present invention will be described.

Limiting voltage EC of filter capacitor 4 (Fig. 5)
It is taken out via the voltage detector 18 connected via 19 and given to the comparator 27. Comparator 27 has lower threshold V
With a hysteresis of D and upper threshold VU, disconnection and re-adhesion are detected based on the input voltage EC, and signals of L and H are output upon disconnection and re-adhesion. The output of the comparator 27, as shown in FIG.
On-delay time to allow time for EC to stabilize
Through an on-delay timer 28 having a TD, it is led to an AND gate 31 (FIG. 1) as a starting condition on the one hand and to an AND gate 33 as a conduction ratio control condition on the other hand.

FIG. 1 shows an example in which the algorithm of FIG. 3 is incorporated into the control device of FIG. 6 as an embodiment of the present invention.
For the output signal of the on-delay timer 28, one of the activation conditions and the logical product is taken by the AND gate 31, and the changeover switch 24 is controlled by the output signal of the AND gate 31. The output signal of the on-delay timer 28 is input to another AND gate 33, and is used as a condition signal for inputting the duty ratio control signal α from the constant current control device 25 to the gate amplifier 26. The change-over switch 22 is changed over to the H side via the AND gate 32 under the condition that the output signal of the AND gate 31 is "H", according to the current reduction condition.

Now, as shown in the time chart of FIG. 2, when the line is disconnected at point A, the filter capacitor voltage EC decreases and reaches the comparator lower threshold value VD at point E, the changeover switches 22, 24
Is switched to the L side and the current command value IC = 0,
The chopper flow rate also becomes α = 0. Therefore, the voltage EC of the filter capacitor 4 does not decrease much from the voltage value at point E thereafter. After a short time, the line is re-attached at the point F, and when the voltage EC rises and reaches the comparator upper threshold VU at the point G, the output of the comparator 27 is inverted to "H", and from this point, after the time period TD, The changeover switches 22 and 24 are switched to the H side, and the current command value IC rises from 0 with a primary delay represented by the primary delay circuit 23. In accordance with this, the chopper conduction ratio α becomes the motor current IA = IC = IC. Is controlled via the constant current controller 25.

In the above control process, the chopper 8 is stopped when the filter capacitor voltage EC drops to the lower threshold value VD of the comparator 27 at the time of disconnection, so that the filter capacitor voltage drops significantly below the lower threshold value VD of the comparator 27. There is nothing to do. Therefore, it is possible to suppress the overshoot of the filter capacitor voltage at the time of reattachment.

〔The invention's effect〕

As described above, according to the present invention, the voltage drops to a predetermined value or less when the wire is disconnected, the chopper conduction ratio α is set to zero, the chopper is stopped, and the electric current of the motor is adjusted from zero to a predetermined value with a delay time when reattaching. By gradually increasing to the value,
It is possible to prevent an overcurrent of the electric motor, or prevent damage to a device such as a chopper due to an overcurrent. Also, in the case of short-time de-railing, sequence operations such as re-closing of switches such as line breakers and high-speed circuit breakers are not required at the time of restarting after re-adhesion, and smooth operation is possible even in line situations where de-railing occurs frequently. It is possible to restart.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a control device of the present invention, FIG. 2 is a time chart for explaining a control operation by the device of FIG. 1, and FIG. 3 is a main part of the device of FIG. FIG. 4 is a block diagram for explaining the algorithm of FIG.
FIG. 5 is a time chart showing the characteristics of the on-delay timer shown in FIG. 5, FIG. 5 is a connection diagram showing the main circuit configuration of an electric vehicle to which the present invention is applied, and FIG. 6 is a block diagram of a conventional control device.
FIG. 8 is a time chart showing the mutual relationship among the starting condition, the current reducing condition, and the armature current command value in the device of FIG.
The figure is a conceptual diagram showing the response of the filter capacitor voltage in the conventional device at the time of disconnection and re-connection. 1 ... Pantograph, 4 ... Filter capacitor, 5 ...
… DC series motor, 8… Main chopper, 21… Current limit value setting device, 22, 24… Changeover switch, 25… Constant current control device, 27… Hysteresis comparator, 28… On-delay timer .

Claims (1)

[Claims] 1. An electric vehicle for controlling a current supplied from an overhead wire via a pantograph and a switch to a DC electric motor for driving an electric vehicle, in which a filter capacitor is connected in parallel, via a chopper so as to match a current command value. In the control device, the disconnection of the pantograph is detected because the voltage of the filter capacitor has decreased to a lower threshold value that does not reach zero, and the stable voltage of the filter capacitor is exceeded above the lower threshold value. Detecting means for detecting re-attachment of the pantograph by rising to an upper threshold value that does not reach, and turning off the chopper without opening the switch by the disconnection detection output of the detecting means, and the current command Means for making the value zero, delay means for delaying the re-adhesion detection output of the detection means, and re-delay delayed by this delay means. The electric vehicle controller, characterized by comprising a means for gradually increasing from zero the current command value as well as to turn on the chopper by a line detection output to a predetermined limiting value with a first-order lag.