JPS5814119Y2 - DC electric railway power supply system - Google Patents

Description

[Detailed description of the invention] This invention relates to a power supply system for DC electric railways, and in particular, a new power supply system that reduces the number of applied DC high-speed circuit breakers as much as possible to reduce the equipment cost of the entire power supply system. The aim is to provide a system.

As a configuration of a substation applied to a power supply system of a DC electric railway, an example of the configuration shown in FIG. 1 is generally known.

In the figure, 1 is a three-phase commercial frequency power supply bus, and under this power supply bus are AC breakers 2□, 2゜, transformers 3□, 3□, raw power converters 4□, 4゜, and a disconnector 5□. , 5° are connected in series.

The forward power converters 4□ and 42 convert input AC power into DC power, and conventionally had a configuration in which diodes were connected in a bridge, but recently, systems in which thyristors were connected in a pure bridge are being applied. .

8 is a row bus (also called a DC positive pole bus), and under this bus there are a DC high-speed circuit breaker group 61, 64 and a disconnector group 1□ to 74.
are connected in series, respectively, and desired DC power is supplied to the feeder wires 101 and 10□ from the disconnector groups 1□ to 14.

Note that 9 is the negative electrode bus bar, 11□. 11° is the rail of the electric car, and L is the steering wheel for limiting overcurrent.This reactor can be omitted without any problem in operation.

The substation shown in Figure 1 is an example dedicated to the power line; however, if a regeneration function is to be added, for example, a reverse power conversion device is installed between the power line bus 8 and the commercial frequency power supply bus 1 shown in Figure 1. What is necessary is to insert a series connection of a reverse conversion transformer, and an AC breaker, respectively.

Since the operation of a substation with the above configuration is well known, only the configuration will be mentioned.

As is clear from the configuration diagram in Figure 1, 2 including the upper 9-lower ji
In the case of a line, four sets of DC high-speed circuit breakers 6□ to 64 are used.

As is well known, these DC type high-speed circuit breakers are mechanically based mechanisms, so firstly, it is extremely troublesome to adjust the mechanical system and maintain it due to changes over time. It is.

Second, the circuit breaker itself is dog-shaped, and this circuit breaker can be divided into 4
Since the substation is also used, the area occupied by the equipment itself becomes very large, and the equipment cost of the substation itself becomes extremely uneconomical.

The present invention has been devised in view of this point, and will be described in detail below based on the embodiment shown in FIG.

Components in Figure 2 that are the same as those in Figure 1 are given the same reference numerals.
The feature of this embodiment is that the stopper diode groups 12□ to 12 are connected under the DC positive electrode bus 8, and are positioned with the polarity shown in the figure instead of, for example, a DC high-speed circuit breaker.
4, these stopper diode groups are shown in figure A.
It also has the function of blocking the loop power flowing in from a substation group (not shown) adjacent to the substation, and for example 12. and 12
The arms into which the 12° and 123 elements are inserted are connected by one DC high-speed circuit breaker 65, and the arms into which the 12° and 123 elements are inserted are connected by the other DC high-speed circuit breaker 6.
6 are connected to form a substation.

Now, to describe the operation of the present application having the above configuration, during normal operation, AC power input from the commercial frequency power supply bus 1 is transferred to the transformer 3.
□, 32 step down the voltage to an appropriate voltage value, and the forward power converter 4□, 42 converts this step-down power into DC power, and this DC power is passed through the disconnector 5□, 5° to the bottom of the DC positive bus 8. input to the stopper diode group 12 □ 124 and the disconnector groups 11 to 14 connected to the switch group 71 to 14, and to the vehicle (not shown) connected to each feeder line 10 □, 10° below the disconnector group 71 to 14. It supplies direct current power by treating it as power.

In addition to the above route, the power to be supplied to navigating vehicles is
For example, stopper diode 121→breaker 65. Disconnector 74 or stopper diode 124 → circuit breaker 65
→Disconnector 10, and further stopper diode 12□→
Breaker 66 → Disconnector γ3 or stopper diode 1
Needless to say, there are loops of 23→breaker 66→disconnector 1°.

During this steady state, for example, for some reason, a short circuit occurs between substation A shown in Figure 2 and a substation (not shown) adjacent to this substation, and this short circuit occurs in the feeder line of 10□. Assume that

In the case of such a short circuit accident, as is well known, in order to immediately stop the power supply to the A substation adjacent to the accident section and the unillustrated substation adjacent to this substation, for example, the forward power of both substations is If the converter has a configuration in which thyristors are connected in a pure bridge, the gates of the thyristor group are narrowed down to the minimum position to stop power supply to both substations, and then the disconnector connected to the faulty circuit is opened to disconnect the fault section. This is exactly the same as the conventional power supply system.

A problem that arises at the time of such an accidental shut-off is, for example, when all DC type high-speed circuit breakers are replaced with only a group of stopper diodes as shown in FIG. 2.

With such a power supply system, the power supply to both substations sandwiching the accident point will be cut off until the accident is completely recovered.
For example, if there is a car on the healthy line 10° that is installed parallel to the accident line 10□, this car will continue to drive while the accident continues.
The operation has to be stopped.

Problems like this must be resolved as part of our one-dog mission to ensure smooth operation.

In this regard, in the present application, each arm of stopper diodes 121 and 124 arranged across dead sections 01 and 02 in substation A shown in FIG. Since DC high-speed circuit breakers 65 and 66 are provided to connect each arm to each other, in the event that a short circuit occurs at the above-mentioned fault point, the A substation sandwiching the fault point Almost at the same time as the power supply to a healthy substation (not shown) adjacent to the substation is stopped, the disconnectors γ2 and 73 on the healthy line 102 are closed, and the disconnectors 12 and 124 on the fault circuit 10 and side are closed.
Open the terminal to isolate only the fault point from the healthy bus.

Based on these operations, even if both substations that sandwich the fault point have stopped supplying power, the DC high-speed circuit breaker 66 on the 10° side of the healthy circuit is still in the closed state, so the second Recirculating power supply line 102- from a healthy substation (not shown) adjacent to substation A in the figure + disconnect switch 72 of substation A → DC high-speed circuit breaker 66 → disconnect switch 73 → healthy line installed in parallel with fault line 101 The electric power flows through the route of the motor vehicles connected to the line 10□ → the rails → the negative bus bar, and the electric power is supplied to the motor vehicle as the motor power so that the predetermined motor vehicle can be driven.

Nafu/DC high speed circuit breaker 65y66 has the same functionality, for example, a configuration in which thyristors are connected in antiparallel.
It is also possible to apply a thyristor circuit breaker, and if a thyristor circuit breaker is applied in this way, the substation structure itself will be composed of almost stationary parts. It is possible to simplify maintenance and further improve reliability.

As described above, the present invention is a system that minimizes the number of DC type high-speed circuit breakers that are conventionally known in the configuration of substations installed in the power supply system, so it has various effects as shown below. It is based on

■ If the number of circuits in the power supply system is two, the number of DC high-speed circuit breakers applied can be halved compared to the conventional method, which of course can sufficiently eliminate the complexity of maintenance. This has the advantage that the equipment cost of the substation itself can be made even cheaper.

■ Since the DC type high-speed circuit breaker is configured with stationary stopper diodes to the extent possible, an extremely reliable power supply system can be realized in combination with the effect of item (■) above.

■ If the DC high-speed circuit breaker is replaced with a thyristor circuit breaker, the interruption time will be shortened, and it will be easier to coordinate protection in the event of an accident, resulting in an even more reliable power supply system. It can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a specific example showing a typical configuration diagram of a substation installed in a power supply system of a DC electric railway, and FIG. 2 is a specific example of a power supply system showing an embodiment of the present invention. 1 is a commercial frequency power supply bus, 4□, 42 is a forward power converter,
5□, 52 and 71, 74 are disconnectors, 65, 66 are DC high-speed circuit breakers, 8 is a DC positive electrode bus, 9 is a negative electrode bus, 1
01.102 is a feeder wire, 121-124 are stopper diodes.

Claims (1)

[Claims for Utility Model Registration] ■ AC power input from a commercial frequency power supply bus is converted into DC power by a raw power converter, and this DC power is converted into a DC positive electrode provided on the DC output side of the raw power converter. bus line and
In a system in which power is supplied to each feeder line through a group of disconnectors placed under the DC positive bus, the direction of flow between the DC positive bus and each disconnector is from the DC positive bus to the disconnector. A feature is that a group of stopper diodes with fine polarities are inserted, and in each arm into which these stopper diodes are inserted, the arms that face each other with the dead section of the feeder line in between are connected with a DC breaker. DC electric railway power supply system. (2) A power supply system for a DC electric railway according to claim 1, which applies a thyristor circuit breaker having a structure in which thyristors are connected in antiparallel or a DC high-speed circuit breaker as a DC circuit breaker.