JPS60110539A - Electricity feeding device of dc electric railway - Google Patents

Abstract

PURPOSE:To smoothly switch the power running/regenerative running by inserting a regenerative thyristor breaker in a DC positive electrode bus line and inserting a breaker for cutting off a DC current flowing into the reverse power converter side. CONSTITUTION:During the power running of a car 11, the current feeding system of a DC electric railway feeds the power running powr through a forward power converter 1 power running thyristor breaker 43 a disconnecting switch 53 a current feeder 61 the car 11 a rail 71 a negative electrode bus line 10. During the degenerative running, the regenerative power from the car 11 flows to the commercial-power supply bus line side through the car 11 the current feeder 61 the disconnecting switch 53 a diode 82 a degenerative thyristor breaker 9 a reverse power converter 2. In this case, the regenerative thyristor breaker is inserted in a DC positive electrode bus line 3 connected with the anode sides of power running thyristor breakers 41-44, and a DC high-speed breaker 13 is inserted in the DC bus line side of the reverse power converter 2 respectively.

Description

[Detailed Description of the Invention] The present invention relates to a power supply device for a DC electric railway mainly based on semiconductor switchgear, which facilitates protection coordination in the event of an accident, and facilitates the transition from continuous operation to regenerative operation. The aim is to provide a power supply device that can perform this smoothly.

In DC power supply systems, arcless power supply systems using semiconductor switchgears are becoming mainstream. A typical example of such a power supply system is shown in Figure 1, which shows a thyristor rectifier or 8-digit thyristor rectifier that is configured by connecting lid thyristors in a pure bridge and converts AC input power into DC power. This is an inverse power conversion device that reversely converts the regenerated power of a 2-car vehicle into AC power using a 1@power conversion device such as a silicon rectifier connected with a diode bridge. 3Fi DC positive electrode bus, 41 to 44 are each DC power line. These circuit breakers include a main thyristor, a forced arc-extinguishing circuit connected in parallel to the main thyristor, and consisting of a commutating capacitor, a commutating reactor, and an auxiliary thyristor. It consists of a charging circuit etc. that charges a commutating capacitor with a desired charge. 51 to 54 are disconnectors, 6
1-62 are chain wheels, 71-7! are rails, 81 to 84 are regenerative diodes for guiding regenerative power to the DC positive bus 3 side, 9 are regenerative circuit breakers for cutting off regenerative power, etc., and 10 are each rail and J@power converter. This is a negative electrode bus that connects to the negative electrode side bus.

When the vehicle 11 is in power mode in the chain wheel system configured as described above, the sequence is forward power converter 1 → DC positive bus 3 → power running thyristor circuit breaker 43 → disconnector 53 → feeder line 61 → vehicle 11 A desired power is supplied through the path of →rail 71→negative bus bar 10. On the other hand, when the vehicle 11 is in regenerative operation, a gate signal is applied to the element group of the inverse power converter 2 to turn it on, thereby gate blocking the forward power converter 1. However, the regenerative power of the vehicle is 11
→ Feeder line 61 → Disconnector 53 → Diode 824 Regeneration thyristor circuit breaker 9 → Reverse power converter 2 The flow is routed to the commercial power bus, and the vehicle 11 → Feeder line 6
1 → Disconnector 53 → Diode 82 → Cyristor circuit breaker 9 → Straight (Af, positive electrode bus 3 → Cyristor circuit breaker for power running 4
1 (or 44)→disconnector 51 (or 54)→feeder line 62, the power is supplied to a vehicle (not shown) as power. If a ground fault occurs at the point shown in the figure during such regeneration, the vehicle 11→feeder line 61→disconnector 53
→ Diode 82 → Regeneration circuit breaker 9 → DC positive electrode bus 3 → Power running circuit breaker 44 → Disconnector 54 →
The fault current flowing in the path from the feeder line 62 to the fault point ■ is interrupted by forcibly extinguishing the regenerative thyristor circuit breaker 9, and the fault current flowing from the forward power converter is interrupted by the forwarding thyristor circuit breaker 44. Block it with. When these fault currents become approximately zero, the disconnector 54 is opened to cut off only the fault line.

In this way, with the conventional device shown in Figure 1, there is no problem in steady state or in the event of a ground fault on the feeder line side, but for example, during regeneration, the reverse power converter 2 may fail in commutation due to fluctuations in the voltage on the power supply side. In the event of an accident, the forward power converter R1 → DC positive bus 3, and the forward power converter l → DC positive bus 3 → each line circuit circulator 41 to 44 → each regeneration diode 81 to The fault current from the power supply side, furthermore, the regenerative power from the vehicle and the incoming power from the adjacent substation flow through the path of 84→regenerative thyristor circuit breaker-9. These fault currents will cause regeneration of the circuit breaker 9.
The fault current flowing through can be interrupted by circuit breaker 9,
The fault current flowing directly through the forward power converter 1 continues to flow until the forward power converter 1 is gate shifted or gate blocked to limit the flow and cut off the energy stored in the power source inductance. Since this fault current has a very steep rise and a large force, it may develop into a serious accident that permanently destroys the elements of the forward-reverse power converter. A further problem is that when shifting to regenerative operation, the regeneration setting voltage value at which the reverse power converter 2 operates must be set slightly higher than the no-load DC voltage value of the forward power converter R1. Therefore, if the start operation of the inverse power converter is delayed, the closed-lane voltage will rise abnormally, posing a threat to equipment at the substation and equipment on the vehicle side. Therefore, in the event of an abnormal increase in the voltage of closed lanes caused by a delay in the operation of the inverse power converter, it would be difficult if the vehicle side had to switch from regenerative braking to air ttflJ ijI or dynamic braking to deal with it, but this braking method Switching means deactivation of regeneration and goes against the trend of energy-saving chain wheel systems, which is not desirable.

The present invention was invented in view of this point, and a J flow speed circuit breaker or a semiconductor circuit breaker is inserted into the DC positive electrode bus and the reverse power converter + MJ, and this circuit breaker and each row thyristor circuit breaker are connected to each other. A regenerative thyristor circuit breaker is inserted into the DC positive bus that connects the anode side common connection point to provide protection coordination in the event of an accident, and will be described in detail below based on an actual example shown in FIG.

In the embodiment of FIG. 2, the same parts as in FIG. , a regenerative thyristor circuit breaker inserted with the polarity shown in the figure.This circuit breaker is connected to a series circuit of the main thyristor 14, the auxiliary thyristor 15, the commutating reactor 16, and the commutating capacitor 17, as shown in FIG. A thyristor (JLC diode) 18 for applying a bias voltage and an inverting thyristor 19 for inverting a reverse charge with a polarity opposite to that shown in the figure.
The Vh (not shown) is composed of an AC R power supply for charging the commutating capacitor 17 with the polarity shown in the figure, a rectifier circuit, and a charging circuit such as a current suppressing resistor. This regenerative thyristor speed 1 analyzer is in a conductive state during normal operation, and is forcibly extinguished in order to discharge the scattering current (regenerative power or M-containing power) that flows in at the time of an accident. Reference numeral 13 denotes a DC high-speed circuit breaker inserted into the DC bus side of the reverse power converter 2, which interrupts the fault current flowing in when the reverse power converter fails to commutate. If a thyristor circuit breaker is used instead, the power supply device can be completely arc-free.

. To describe the operation of the present invention configured as described above, when operating the reverse power converter R2 during regeneration, in the conventional device shown in FIG. Although it was set to be slightly higher than the no-load DC voltage, in this application, one person was connected to the DC positive bus 3 as shown in the regenerative thyristor circuit breaker 12, so the forward power converter l and the reverse power converter 2 During parallel operation, device 21! lI
Since the power flowing into the inverter is blocked by the regenerative thyristor circuit breaker 12, the inverter setting voltage of the reverse power converter e2 can be set lower than the no-load DC voltage, which causes a slight delay in the start of operation of the reverse power converter. Even in such cases, operation can be started when the feeder voltage is equal to or lower than the no-load DC voltage, and regeneration will never fail.

Next, to describe the operation at the time of an accident, when the reverse power converter 2 and the power converter l are operated in parallel, the reverse power converter 2 is switched due to factors such as VC and large distortion of the commercial power supply voltage waveform. If the flow fails.

According to this embodiment, the fault current from the J@power converter l that attempts to flow directly into the accident aircraft is blocked by the regenerative thyristor circuit breaker 12, and if the vehicle 11 is in regenerative operation,
The regenerative power that is about to flow into this regenerative vehicle and the accident,
Or M, which is trying to flow into the accident aircraft from a substation adjacent to the illustrated substation! Each of the 7 included power is cut off by 13 circuit breakers. In this way, according to this embodiment, even if the reverse power converter 2 fails to commutate, all the fault currents that could be expected to flow into the faulty aircraft are cut off by Mi or blocked by U, thereby preventing the inverter from failing in the event of a fault. This has the advantage that the operation of the power converter can be continued even when the power converter is in use, and the effects of an accident can be minimized. Furthermore, in the event that a ground fault occurs in the vehicle 11 at the zero point shown on the feeder line 62 side during regeneration, in this embodiment, a group of overcurrent relays (not shown) inserted into each DC line are connected to the faulty feeder line. Only the overcurrent relay inserted in the direct I/C line operates, and the output signal of this relay is used to interrupt the fault current flowing from the forward power converter 1 at the fault line thyristor breaker 44 of the fault line.

In parallel with this operation, the auxiliary thyristor 5 shown in FIG. 3 of the regenerative thyristor circuit breaker 12 is ignited using the output signal of the overcurrent relay. However, Teri 13 figure's transformation MC/
Deno? The charge that is charged with the polarity shown in the 17Vc diagram is discharged through the path of commutating CO/DEN+17 → main thyristor 14 → auxiliary thyristor 15 → commutating reactor 16, and the value of the discharge current that becomes free oscillation is the value of the discharge current in the main thyristor. 1
When the fault current (the total sum of the regenerated power and the included power) flowing through the main thyristor 14 is reached, the main thyristor 14
is forcibly extinguished, and then the released r5 current flows through the path of commutating diode 18 → auxiliary thyristor 15 → commutating IW and reactor 16, and the inflow fault current flows through auxiliary thyristor 15 → commutating reactor 16 → commutating capacitor. 17, and the reverse charging of the commutating capacitor 17 progresses further. When the reverse charging voltage value (inversion voltage) of the commutating capacitor 17 reaches the starting level, the auxiliary thyristor 15 is naturally extinguished, and fault current such as regenerative power is completely cut off. Note that the reversed charge is transferred to commutation capacitor 1.
The inverting thyristor 19 connected in parallel to 7 is fired to invert the illustrated polarity again. The charging energy lost when such regenerative power is cut off is replenished by a charging circuit (not shown) to restore the initial state.

As described above, in the present invention, a regenerative thyristor breaker is inserted into the DC positive bus, and a breaker is inserted to interrupt the direct current flowing into the reverse power converter side. Therefore, various effects can be achieved as shown below.

(1) Since the set voltage of the reverse power converter can be set lower than the no-load DC voltage, it is possible to smoothly transition from power driving to regenerative operation, and even from regenerative driving to deer driving, and the reverse power converter can Even if it is delayed, problems such as failure of regeneration due to increase in feeder line voltage, which is seen in conventional devices, can be prevented.

(2) Even if the reverse power converter fails to commutate, the fault current flowing directly into the forward power converter can be blocked by the regenerative thyristor circuit breaker, allowing protection coordination to prevent the spread of the fault. becomes very easy to take.

(3) By simply replacing the insertion point of the regenerative thyristor circuit breaker without increasing the number of parts, the above (1) can be achieved.
Since the effects shown in (2) and (2) are achieved, the equipment cost of the power supply device can be greatly reduced.

(4) Since the η problem such as regeneration failure is completely eliminated,
It is possible to effectively utilize regenerative energy and realize an energy-saving power supply device.

[Brief explanation of the drawing]

FIG. 1 is a specific circuit configuration diagram showing a conventional power supply device, and FIG. 2 is a power supply device showing an embodiment according to the present invention. 1: A specific circuit configuration diagram of the device; FIG. 3 is a specific circuit configuration diagram of a regenerative thyristor breaker applied to the power supply device. 1 is a J@power converter, 2 is a reverse power converter, 3 is a DC positive bus 441 to 44 is a thyristor circuit breaker for rows 51
~54 is a disconnector, 8! ~8<l'i regeneration diode,
1O is a negative electrode motherboard a, 12 is a regenerative thyristor breaker, 13
is a DC breaker.

Claims (1)

[Claims] A forward conversion device that converts AC input power into DC power, a DC positive busbar provided on the DC output side of this device, and a power line thyristor breaker and disconnector connected under this busbar are connected in series. Seven nodes are separately connected to the plurality of sets of DC circuits and the cathode of the thyristor circuit breaker for each row,
and a plurality of regeneration diodes connecting the DC positive bus to a connection point where each cathode is connected in common, and a plurality of regeneration diodes provided on the DC positive bus to convert the DC power led by the regeneration diodes into AC power. A reverse power conversion device to be converted, a DC breaker provided between this device and the DC positive bus, an anode connected to a connection point connecting the regeneration diode and the DC positive bus, and forward power conversion A power supply device for a DC electric railway, comprising a regenerative thyristor circuit breaker that blocks current flowing into the forward power converter and the reverse power converter when the device and the reverse power converter are operated in parallel. .