JPH02193727A - Direct current feeding system - Google Patents

Abstract

PURPOSE:To attempt improvement in regenerating efficiency by connecting each of feeder lines to a solid breaker through diodes and by connecting output of the solid breaker to feeder lines through diodes. CONSTITUTION:Regenerative electric power from feeder lines 31 and 32 is supplied to other feeder lines 31 and 32 through a diode 24 or 25, a solid breaker 23 and a diode 27 or 26. That is, regenerative power from the feeder line 32 is supplied to the feeder line 31 through the diode 25, the solid breaker 23 and the diode 26, and regenerative power from the feeder line 31 is supplied to the feeder line 32 through the diode 24, the solid breaker 23 and the diode 27. When a solid breaker 22 for feeding fails, direct current power is supplied to the feeder line 32 through the diode 24, the solid breaker 23 and the diode 27, and extended feeding is carried out. Accordingly, as regenerative power can be supplied to other feeder lines through two diodes and one solid breaker, power loss is small and regenerating efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a DC feeding system for supplying DC power to feeder lines for electric railways.

(Prior Art) In recent years, there has been an increase in the number of DC feeding systems using solid state DC breaker devices using semiconductors.

A conventional DC feeding system is shown in Figure 4. In Fig. 4, 11 is a rectifier that converts AC power into DC power and supplies DC power to the feeder line; 12 is a DC bus; 21, 22
A solid circuit breaker that switches on and off the DC power supplied to feeder lines;
23 is a solid breaker for regeneration that supplies regenerated power from the feeder line to other feeder lines; 24; 25 is a diode that supplies regenerated power from the feeder line to the solid breaker 23; 31.
32 is a feeder line, 33 is a feeder line 3 for extended feeding.
This is a disconnector that connects the electric wire 32 at one time.

In the DC feeding system shown in FIG.
DC power is supplied to the feeder line 32 through the solid breaker 21 and to the feeder line 32 through the solid breaker 22 .

If an accident occurs on the feeder line and an overcurrent occurs, the solid state breaker that supplies DC power to the feeder line will shut off and protect the line. Regenerative power from the feeder line is diode 24
Alternatively, it is supplied to other feeder lines through the diode 25 and the solid state breaker 23. For example, the regenerated power from the feeder line 32 is transferred to the diode 24, the solid state breaker 23, the DC bus 12,
It is supplied to the feeder line 31 through the solid breaker 21. Further, if the solid breaker 21 or the solid breaker 22 fails, the disconnector 33 is turned on and power is extended from the adjacent substation. For example, if the solid breaker 22 fails,
Electricity is supplied from the feeder line 31 to the feeder line 32 through the disconnector 33.

(Problems to be Solved by the Invention) In the DC feeding system as described above, regenerated power from a feeder line is supplied to other feeder lines through two solid circuit breakers and one diode. In general, elements such as turn-off thyristors have a larger voltage drop than diodes, and in the above system, two solid-state circuit breakers are used, resulting in large power loss and poor regeneration efficiency.

On the other hand, if the solid state breaker 22 fails, the disconnector 33 is turned on to provide extended power supply, but there are constraints such as the state of the system in order to turn on the disconnector.

Since it is not possible to supply power at high speed, it takes time to reach extended power supply. Further, there are constraints such as the system must be stopped in order to open the disconnector 33 after the solid state breaker 22 is restored, and it takes time to open the disconnector and restore the system. Additionally, the extended feeder section is protected by a breaker at an adjacent substation, but this increases the breaker energy, so the breaker's breaker scale must be lowered. However, since the normal operating current does not change, the cutoff scale cannot be made very low, and protection coordination becomes extremely difficult.

As mentioned above, conventional DC feeding systems have drawbacks such as poor regeneration efficiency, extended feeding time, and poor protection coordination.

An object of the present invention is to eliminate the above-mentioned drawbacks and provide a highly reliable DC feeding system.

[Structure of the invention]

(Means for Solving the Problems) The present invention resides in that a solid state breaker is connected to each feeder line through a diode, and the output of the solid state breaker is connected to the feeder line through the diode.

(Function) According to the present invention, regenerated power from the feeder line is supplied to the solid breaker through the diode, and from the solid breaker to the other feeder line through the diode. In addition, when a heavy duty solid breaker breaks down, DC power is supplied from each feeder line to the other feeder line through the diode, the solid breaker, and the diode. By inserting the above-mentioned solid breaker, the power supply can be extended immediately.

(Example) An example according to the present invention is shown in FIG. Components that are the same as those in FIG. 4 are designated by the same numbers. Diodes 26 and 27 supply DC power that has passed through the solid state breaker to the feeder fi 31 and the feeder line 32, respectively. The difference from FIG. 4 is that the output of the solid state circuit breaker 23 is connected to the feeder line through diodes 26 and 27, and that there is no disconnector 33.

(Operation of the Embodiment) In the DC feeding system shown in FIG. 1, regenerated power from the feeder line is supplied to other feeder lines through the diode 24 or 25, the solid state breaker 23, and the diode 27 or diode 26. Regenerative power from the feeder line 32 is transmitted through a diode 25, a solid breaker 23. The regenerated power is supplied to the feeder line 31 through the diode 26, and the regenerated power from the feeder line 31 is passed through the diode 24, the solid state breaker 23, and the diode 27.
It is supplied to the feeder line 32 through.

If the solid state breaker for the heavy load fails, for example, if the solid state breaker 22 fails, DC power is supplied to the feeder line 32 through the diode 24, the solid state breaker 23, and the diode 27, and extended power feeding is performed. It will be done. Even if the solid state breaker 21 fails, extended power feeding can be similarly performed through the diode 25, the solid state breaker 23, and the diode 26.

According to this embodiment, since the regenerated power is supplied to other feeder lines through two diodes and one solid state breaker, it is supplied to other feeder lines through one diode and two solid state breakers as shown in It has less power loss and better regeneration efficiency than those that supply electricity.

Moreover, since the solid breaker 23 is turned on for regeneration, even if the solid breaker 21 or the solid breaker 22 fails, extended power feeding can be performed instantaneously. solid breaker 2
3, the extension type portion can be protected by the solid breaker 23, and protection coordination is easy.

Although FIG. 1 shows the case of two systems of feeding power, FIG. 2 shows the case of four systems of feeding power. In FIG. 1, a solid breaker 41, a diode 43, and a diode 45 are connected corresponding to the feeding line 1a36, and a solid breaker 4 is connected corresponding to the feeding line 35.
2, a diode 44 and a diode 46 are connected. Even in the case of the four systems shown in FIG. 2, the same effects as in FIG. 1 can be obtained.

FIG. 3 shows another embodiment according to the invention. The difference from FIG. 1 is that a disconnector 29 is connected between the diode 24 and the diode 26 and the electric wire 31, and a disconnector 30 is connected between the diode 25 and the diode 27 and the electric wire 32.

Solid breaker 23 and DC flow #! The reason is that a disconnector 28 is connected between 12 and 12. In FIG. 3, normally the disconnector 29
, and put it into the disconnector 30. In this state, the same effect as in FIG. 1 can be obtained by the same action. In FIG. 3, when solid breaker 21 fails, solid breaker 23 can be used as a backup device by turning on disconnector 28 and 29 and opening disconnector 30. Similarly, when the solid breaker 22 fails, the breaker 28
By turning on the disconnector 30 and opening the disconnector 29, it can be used as a backup device. In addition to the above-mentioned effects, the embodiment shown in FIG. 3 also has the advantage that the solid breaker 23 can be used as a backup device for the solid breaker 21 and 22.

〔Effect of the invention〕

As described above, according to the present invention, power loss is low, extended feeding can be performed sequentially, and a highly reliable DC feeding system can be provided. Furthermore, by adding a disconnector, it can be used as a standby device, and a more reliable DC feeding system can be provided.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of a DC feeding system according to the present invention, FIGS. 2 and 3 are diagrams showing other different embodiments of the present invention, and FIG. 4 is a diagram showing a conventional DC feeding system. It is a figure which shows an example. 11... Rectifier ・12... DC bus 21
, 22.23.41.42...Solid breaker 24, 2
5.26.27.43.44.45.46...Diode 28, 29.30...Disconnector 31.32.35
．． 36...Feeder line agent Patent attorney Nori Chika Ken Yudo Daishimaru Ken Figure 1

Claims (1)

[Claims] In a DC feeding system that supplies DC power to each feeder line through a solid state breaker, a series circuit consisting of a pair of series-connected diodes is provided corresponding to the number of the feeder lines, and the series circuit of the series circuit is Connect the connection points to each feeder line, connect the cathode sides of the series circuit all together to the input side of the solid state breaker, and connect the anode sides of the series circuit all together to the output side of the solid state breaker. A DC feeding system characterized by: