JPS62221939A - Dc feeding voltage decrease compensating device - Google Patents

Abstract

PURPOSE:To decide securely in which side in the up and down lines an accident occurs, by furnishing a circuit system consisting of a diode bridge circuit and a semiconductor breaker, and making it possible to select the current direction. CONSTITUTION:If a grounding short circuit is generated at a point a, as well as DC high speed breakers 54F12 and 54F22 are operated, an accident current flows from a feeding line T1 through a diode bridge circuit DBG and a semiconductor breaker GTOCB. By this current, a relay Ry is operated to output the breaking instruction, and the semiconductor breaker GTOCB operates. Since this breaking is operated instantly, only very small input current amount flows to the line T2. And the direction of the accident current is determined by the relay Ry to decide in which side of lines the accident occurs. Moreover, by monitoring the rail potentials at points P, P11, and P12, the section of the accident can be determined.

Description

DETAILED DESCRIPTION OF THE INVENTION Δ, Industrial Field of Application This invention relates to a voltage drop compensator in a direct current electric railway that ensures protection in the event of an accident.

B1 Summary of the Invention This invention is an end voltage drop compensation device for DC electric railways, in which a device consisting of a diode Blitzno circuit and a semiconductor breaker is connected to the central position of the up and down feeder lines. This was designed to compensate for voltage drops and provide reliable protection in the event of an accident.

C. Prior Art FIGS. 3 and 4 are configuration explanatory diagrams showing a conventional voltage drop compensation method (tie-post method). First, FIG. 3 will be described. In Figure 3, ss,, ss are substations, 54
F,..., 54F+2 and 54Ft+, 54Ftt are DC high speed breaker, T1. T2 is an end type line, P...
r'2 is a position approximately in the center of substations SS, and R2 is a rail. 1) Step position P,, P
, a DC high-speed breaker 54I' connected in antiparallel between
, 541', are connected. This breaker 54P...
54P can only cut off the fault current in the direction of the arrow shown in the figure.

Figure 4 shows the section S1.L on the tramway. S
t is provided, so in the case of this Fig. 4, DC high-speed circuit breakers 54P, ~54P,
Provide 4 pieces of 4.

D8 Problems to be solved by the invention The device shown in Fig. 3 is a DC high speed breaker 54Pl, 54P.
.

There is a problem in that two vehicles are required, and it is difficult to select the accident section. Therefore, as shown in FIG. 4, section S1. If it is possible to select the accident section by installing Sections 1 and 2, one or more DC high-speed circuit breakers will be required, and the reliability of train operation will decrease due to the provision of Sections S, S2. A problem arises.

Means for Solving Problem E1 This invention supplies power from a substation to upstream and downstream end-type lines that connect substations via DC high-speed circuit breakers, and Connect the common connection points of the cathodes and anodes of the diodes that form a diode bridge circuit to each center position separately, and connect the anode of the semiconductor breaker to the diode cathode (connection reading point). The cathode of a semiconductor circuit breaker is connected to the common connection point of the anodes of the diodes in B, and an accident detection device B?1X2g is provided which can select the direction of the current flowing through the diode bridge circuit.

Since the F-acting diode bridge circuit and semiconductor breaker are used, even if a ground fault occurs in the end-type line, the semiconductor breaker can detect and select the cutoff quickly, so the cutoff can be completed before the current increases. Therefore, the flow of current from the healthy line to the faulty line becomes extremely small. In addition, the selection of the section at the time of this accident becomes possible by monitoring the rail potential.

G. Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The same parts as in FIGS. 3 and 4 are denoted by the same reference numerals.

In Figure 1, DBG is a diode bridge circuit,
This diode bridge circuit DBG has four diode bridge circuits shown in the diagram.
It is formed from fourth diodes D1 to D4.

The first part of the diode bridge circuit DBG. A gate turn-off diristor with the polarity shown is connected between the common connection point on the anode side of the third diodes D1 and D3 and the common connection point on the cathode side of the second and fourth diodes D, D, D, etc.
- Connect the conductor breaker GTOCB.

The first part of the diode bridge circuit DBG. The central position P1 of the end type line T1 is connected to the common connection point C1 of the second diodes D, , D, and the third. 4th diode D3゜D4
The central position P2 of the end type line T is connected to the common connection point C9 of the end type line T. Ry is an accident detection relay that has a current direction selection function, and this relay RY is operated by detecting the current flowing in the electrical path connecting the connecting reading point C2 and the center position P2.

Next, the operation of the embodiment configured as described above will be described.

Now, it is assumed that a ground fault occurs at point a in the diagram of end type line T. As a result of this accident, DC high-speed circuit breakers 54F and 2
．． 54F22 operates, a fault current as shown by the dotted line arrow in the figure flows from the end type line T1 through the diode bridge circuit DBG and the semiconductor breaker GTOCB.

This current causes U electric appliance Ry to operate, and semiconductor breaker G
A cutoff command is given to the TOCB.

With this command, the semiconductor breaker GTOCB is operated,
The operating time is within 1 ms from when an accident is detected to when the circuit is shut off. Therefore, the current flowing from the healthy line T1 to the faulty line T becomes extremely small. Further, the +iir register RY determines the direction of the fault current and selects which line side the fault has occurred on.

By using a diode bridge circuit and a semiconductor breaker as described in -, it is possible to determine which of the up and down lines has suffered a JF failure in the event of an accident, and it is also possible to separate the line in which the accident occurred from the healthy line.

Next, the determination of the degree 111 section will be described. This determination is made by always monitoring the rail potentials at points P, P, 1, and P11 in the diagram. The accident is illustrated in the same manner as above.
The rail potential when generated at a point has a distribution characteristic shown by the solid line in FIG. From this characteristic, the potential e of point P and point 211 is
When and e have the following relationship, determine whether the accident occurred between point P and substation S82.

e < 8 ... (1) apap++ Also, when e < e, the accident occurs between point P and SS1 ap
It can be determined that it is ap2I.

Next, when the accident point is the point shown in the figure, the distribution characteristic will be as shown by the dotted line in FIG. From this characteristic, the potential Q at point P and point Pt1
b, and ebp2. When the relationship is as follows, it can be determined that the accident occurred between point P and substation SS1.

bl) tlpt+ ...(2) Also, ebp
<ebpH, it can be determined that the accident occurred between point P and SS2.

In addition, in FIGS. 1 and 2, the distance between points P and P13 and the distance between points 13 and Ptr vary depending on the rail condition, but it is sufficient if they are selected within 30 m to 50 m.

tl, Effects of the Invention As described above, according to the present invention, a circuit device consisting of a diode bridge circuit and a semiconductor breaker is installed in the electric path connecting the upper and lower lines as a voltage drop compensator at the central position between the substation IT1. Because of the interposition, it is possible to determine which track the accident occurred on, and the track where the accident occurred can be removed, but it also has the advantage of being able to determine the section of the accident.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a rail potential distribution characteristic diagram, and FIGS. 3 and 4 are circuit diagrams showing a conventional example of the tie-post system. ss,, ss, ... substation, 54I',, 54F
,,,54F,,,54F,. ...DC high-speed breaker, T,...T,...end type line, 1<1°R7...rail, DIG...diode bridge circuit, GTOC113...semiconductor breaker,
Ry... Accident detection relay.

Claims (1)

[Claims] (1) Power is supplied from the substation to the up and down feeder lines connecting the substations via a DC high-speed breaker, and a diode bridge circuit is installed at the center of each line between the substations. The common connection points of the cathodes and anodes of the diodes constituting the diodes are connected separately, and the anode of the semiconductor breaker is connected to the common connection point of the cathodes of the diodes, and the cathode of the semiconductor breaker is connected to the common connection point of the anodes of the diodes. A DC feed voltage drop compensator comprising: a fault detection relay connected to the diode bridge circuit and capable of selecting the direction of current flowing through the diode bridge circuit.