JPS58201502A - Controller for electric motor vehicle - Google Patents

Abstract

PURPOSE:To enable to select a low resistance value to become non-vibrating state by connecting a series circuit of a semiconductor element which can be deenergized by a gate control and a resistor in parallel with a filter capacitor. CONSTITUTION:When a chopper control operation is interrupted so that the charging voltage of a filter capacitor 5 excessively rises, a voltage detector 13 detects the excess rise of the voltage to conduct a gate turn-off thyristor (GTO) 14, and the charge of the capacitor 5 is discharged. When the voltage is lowered to the prescribed value, the detector 13 extincts the GTO 14. In this manner, even if the value of the resistor 11 is selected to a low value so that a parallel resonance circuit having a filter reactor 4, a filter capacitor 5 and the resistor 11 becomes non-vibration state, a large current which trips the protecting interrupter is not flowed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric vehicle control device for controlling a DC motor for driving an electric vehicle of a DC electric railway, or for controlling an AC motor using an inverter.

In DC electric railways, power is normally supplied to electric cars with the overhead contact line on the positive side and the rails on the negative side, but when controlling the electric car's motor using a chopper control device or inverter control device as a power converter, To control the power given to the motor, alternating current is generated by intermittent direct current.

If this AC component flows directly into the rail circuit, it may affect the track circuit of the signal equipment that uses AC and cause the signal safety equipment to malfunction, so LC filters are inserted on the power supply side of power converters such as power converters and inverters. It is a well-known secret that this prevents the leakage of alternating current.

In an electric vehicle control system using such an LC filter, when the electric vehicle stops powering operation, or when the electric vehicle is performing regenerative operation, a phenomenon such as disconnection between the current collector and the contact line, or a sudden decrease in the regenerative load occurs. If this occurs, a phenomenon occurs in which the capacitor of the LC filter device described above is overcharged and an overvoltage occurs.

An example of conventional methods for preventing capacitor overcharging in response to this phenomenon will be described using a regenerative braking circuit using chopper control.

In Figure 1, l is the overhead contact line connected to the DC power supply,
2 is a current collector from a train such as a pantograph, 3 is a current interrupter, 4 is a filter reactor, and 5 is a filter 77
No. 72, 6 is a diode, 7 is a DC motor, 8 is a current smoothing reactor, 9 is a chopper device, 10 is a power return ground (usually a rail that contacts the wheels via a grounding device), 1
1 is a resistor, 12 is a thyristor, and 13 is a voltage detector that detects the voltage of the filter capacitor 5.

During regenerative braking, if the load for absorbing regenerative power (such as a running train) is interrupted, the charging voltage of the capacitor 5 will rise, but this voltage rise will be detected by the voltage detector 13 and the thyristor 12 will be activated. It is well known that the electric charge in the capacitor 5 is discharged through the resistor 11 by ignition.

In this case, the impedance of the DC power supply circuit including the contact line 1 is extremely small, so if this is ignored, the thyristor 1
When filter reactor 4.2 is conductive, filter reactor 4.2 is conductive. Since the filter capacitor 5 and the resistor 11 form a parallel resonant circuit, its non-oscillation limit is given by the following equation.

Here, 8 is the resistance value of the resistor 11, C is the capacitance of the filter capacitor 5, and L is the inductance of the filter reactor 4.

Generally, the resonant frequency of the filter is the frequency used for signal security equipment 60) 1 blade, 5QH, 3QH, 25H
.

To avoid this, a frequency around 40H is used, filter reactor 4 is 5++aH, and the value of resistor 11 is determined so as to be in a non-vibrating state with respect to the filter capacitor articles of incorporation. If a low resistance value is taken, the power line 1, pantograph 2, and streamer 3 will be connected from the DC power supply.
The current flowing into the resistor 11 via the filter reactor 4 also becomes very large, which may cause a DC power supply maintenance circuit (not shown) to trip. The thyristor 12 may be ignited to discharge the charge in the filter capacitor 5, and the voltage detector 13 may detect that the voltage of the filter capacitor S has decreased to a predetermined value, and the thyristor 12 may be extinguished. For example, when extinguishing an arc using a repulsion pulse type arc extinguishing circuit, it is necessary to install complex arc extinguishing equipment such as a switchboard for arc extinguishing, a commutation reactor, and a capacitor. The generated oscillating current has the disadvantage of causing harmful induction disturbances to the outside.In addition, if the large current flowing in from the overhead contact line 1 is cut off by the current line breaker 3, the current line breaking capacity of the current line breaker 3 must be reduced. In reality, a relatively large resistance value is given to the resistor 11, and the above-mentioned parallel resonant circuit is
It was not possible to change the status to llb. Therefore, if the above-mentioned formula (1) does not hold and an oscillating alternating current flows into the overhead contact line and return circuit, there is a drawback that there is a possibility that safety devices such as signal circuits may malfunction.

The present invention aims to eliminate such drawbacks and provide an electric vehicle control device that does not cause malfunctions in the signal safety device. Figure 2 shows a regenerative brake using chopper control according to an embodiment of the present invention. This shows a circuit, and 14 in the figure is a semiconductor element that can be extinguished by gate control (for example, gate turn-off,
◎ When the chopper control action is interrupted in the 1/s2 diagram and the charging voltage of the filter capacitor +5 increases excessively, the voltage detector 13 detects the excessively increased voltage. is detected, the GTO-14 is made conductive, the charge of the filter capacitor +5 is discharged, and the voltage detector 13 detects that the voltage has decreased to a predetermined value (for example, the rated voltage is 1500V), and the GTO-14 is turned off. By making it arc, it becomes possible to select the resistance value of the resistor 11 that satisfies the non-vibration condition of formula (1). The resistance value of the resistor 11 is assumed to be KQ, 5ρ, and the capacitance of the filter capacitor S is 1000. jF, the time constant is 1.
5 ms, so when the voltage of filter capacitor 5 rises to 2000 V, GTO-14 is ignited, the charge of filter capacitor 5 is discharged, and the voltage becomes 110 V.
The drop to 0VS* is l+as$41.

On the other hand, from the DC power supply to the overhead contact line 11 pantograph, current breaker 3
, the change in the electric current IEj flowing through the filter reactor 4 is expressed by the following equation.

Here, 8 is the DC power supply voltage, L is the inductance of the circuit including the filter reactor, and R is the DC resistance of the circuit.

Therefore, if L = 1500V and L = 5mH, then the current will be about 1500V and L = 5mH.Actually, it is!The current flowing from the DC power supply after 11118111 elapses after the Note GTO-14 is ignited can be made sufficiently small, so it is necessary to maintain the DC power supply. There is no need to trip the disconnector, and there is no need to make the breaking capacity of the circuit breaker 3 particularly large.Furthermore, even if the current flowing into the GTO-14 is cut off through the resistor 11, an extinguishing signal is sent to the GTO-14. No special arc extinguishing device is required, and no oscillating current is generated due to the arc extinguishing action.

In the above explanation, the GTO-14 was used, but the GTO-14 was used.
The same effect can be obtained by using an electrostatic induction thyristor (8I thyristor) that can be extinguished by gate control instead of TO-14. sc, GTO-1 to close or open the resistor 11 to prevent a voltage rise due to overcharging of the filter capacitor 5 of the circuit that controls the inverter.
According to the present invention using 4, there is no need to trip the DC power supply protection disconnector, and because the resistor 11 is inserted, the inflowing current can be cut off, which has a great effect on the electric vehicle control device. ◎

[Brief explanation of the drawing]

FIG. 1 shows a main circuit of a chopper-controlled regenerative brake using a conventionally used filter circuit, and FIG. 2 shows a chopper-controlled immediate brake main circuit using a filter control circuit according to the present invention. 1...Telephone line, 2...Current collector, 3...
- Current interrupter, 4...Filter reactor, S...
...filter capacitor, 6...diode, 7...motor, 8...-smooth sliding axle,
9... Different horn control device, 10... Grounding, 11... Resistor, 12... Thyristor, 1
3... Voltage detector, 14... Semiconductor element that can extinguish the arc by gate control @ Atsushi Doi, Representative of Toyo Denki Manufacturing Co., Ltd.

Claims (1)

[Claims] When the DC power supply is on, the electric motor receives power from the DC power supply via the contact line and the return rail, and when the power is on, the DC power supply supplies power to the Isao motor, and the regenerative special code ζ converts the rotational energy of the Isao motor into the DC power supply. In an electric car equipped with an LC filter for attenuating the alternating current component of the current flowing to the train and return rails due to the operation of the electric power converter and the electric power converter, the An electric vehicle control device characterized in that a series circuit of a semiconductor element and a resistor that can be extinguished by gate control is connected, and a voltage detector is provided to detect the voltage of the capacitor.