JPS61286767A - Trouble point detection system in distribution system - Google Patents

Abstract

PURPOSE:To shorten a detection time and to enable the grasping of a trouble point from a substation, by providing a terminal device for receiving the call-out code from a relay only when trouble was detected and returning a response signal through an overhead earth wire. CONSTITUTION:For example, when it is assumed that earth trouble was generated in the machinery 3 mounted to a utility pole, a power source is applied to a section switch 9 immediately before a trouble point by the cooperation of a substation side apparatus (1-3) and a trouble section separation apparatus (8-10) and the section on an after is separated and, at the same time, a sensor 17 detects the trouble to close a contact 16. Hereupon, a central apparatus injects a relay call-out signal in a high voltage distribution line 5. When the relay 11 receives the call-out signal, a terminal device call-out signal is injected in an overhead earth wire 6 through a signal injector/detector 12. This call-out signal is transmitted only to a terminal device 18 of which the contact 16 is closed and a return signal is injected in the overhead earth wire 6 from the terminal device 18 concerned. The relay receives the return signal and a response signal is returned to the central apparatus 3 through high voltage couplers 7, 4 to make it possible to know the trouble point.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention divides a power distribution line into predetermined sections, and arranges a fault section separation device consisting of a section switch and a time-controlled control device for each section. This invention relates to a round fault point detection method for detecting a fault point or failure point in a power distribution system where, in the event of a fault, the fault section is isolated by the cooperative operation of the substation side central unit and the fault section isolation device.

[Conventional technology]

First, the faulty section separation device will be explained.

Fig. 3 is a schematic diagram showing a general example of a fault section separation device;
FIG. 4 is a time chart for explaining the operation. In addition, in Fig. 3, 1 is a power distribution breaker, 5 is a distribution line, 81 to 83 are time-limited control equipment power transformers, 91 to 95 are sectional switches, 10
1 to 103 are timed control devices. In other words, the fault section separation device is a section switch 91, as is well known.
-93 and time-controlled control devices 101-103, which are installed in each predetermined section of the distribution line 50, and in the event of an accident, the power supply side section switches 91-95 of the faulty section are opened to disconnect the faulty section and beyond. be.

For example, if an accident occurs at point A in Figure 6, the substation will detect this and disconnect the main circuit breaker 1 as shown in Figure 4 (a), so each section switch 91 to 93 will also be connected to the distribution line 5. fJ4 diagram (+=), ()・) by no voltage.

It becomes open as shown in (d). Then, when the circuit breaker 1 is turned on again after a certain period of time (T1), the section switch is switched to 91r92.
However, when the section switch immediately before the fault point (92 in Figure 3) is turned on, the substation detects the failure again and shuts off the main circuit breaker 1 again. At this time, the section switch 92 is locked in the open state by the action of the time-limited control device 102, and automatic closing is no longer possible. Note that when the circuit breaker 1 is turned on again after that (after T2 hours), the faulty section is separated, so power is transmitted only to the healthy section.

Note that T3 in FIG. 4 indicates the detection time limit of each section switch, and T3 in FIG. 4 indicates the output of the fault section display device.

By the way, even if the accident section is separated in this way, another means is required to know at which point in this section the accident occurred. One of the conventional methods used for this purpose is to apply DC high-voltage pulses to isolated sections and detect changes in the direction of the current flowing into the separated section. A point search method is known.

[Problem that the invention seeks to solve]

However, this method requires workers to go to the site and climb a utility pole each time to install an antenna that detects pulsed currents, making work safety and operability difficult and requiring long hours of work. There is a problem.

Therefore, it is an object of the present invention to provide an exploration method that allows fault points to be ascertained while staying at a substation or the like, and that can shorten the detection time.

[Means for solving problems]

Each power distribution section is equipped with a repeater that receives a call signal from the substation's central equipment and injects the call signal into the overhead ground wire, while sensors on each utility pole in the distribution section detect accidents that occur on each pole. A terminal device is provided corresponding to the sensor, and receives a calling signal from the repeater only when an accident is detected, and returns a response signal via the overhead ground wire.

[Effect]

By sending the response signal from the terminal device to the central device via a repeater, the fault point can be detected in a short time while staying at the central device.

〔Example〕

FIG. 1 is a configuration diagram showing an embodiment of this invention, and FIG.
3 is a time chart for explaining the operation shown in the figure. In Fig. 1, 2 is a fault section display device, 3 is a central device, 4 and 7 are high voltage couplers, 5 is a high voltage distribution line, 6 is an overhead ground wire, 11 is a repeater, and 12 is a signal injection/detection device. 13 is a pole installation device (insulator), 14 is a cross arm, 15 is a telephone pole, 16 is a mechanical holding contact, 17 is a sensor, 18 is a terminal device, and the other parts are the same as those shown in FIG.

The repeater 11 is coupled to the central unit 3 via high-voltage couplers 7 , 4 and to the overhead ground wire 6 via a signal injector/detector 12 . This signal injection/detector 12 is shown as one unit, but it consists of a signal injector and a signal detector, which respectively inject and detect signals, and are well known (l injection transformer, search coil On the other hand, the utility pole 15 is equipped with a sensor 17 that detects an accident and closes the contact 16, and a sensor 17 that receives a call signal from the repeater 11 via the contact 16 and the overhead ground wire 6 and sends a response signal. A terminal device 18 is provided for returning the information.

Therefore, for example, if a ground fault occurs in the pole-mounted equipment 13, the substation side equipment (1
, 2, 3) and the fault section isolation device (8, 9, 10), power is applied up to the sectional switch 9 immediately before the fault point, and the subsequent sections are separated. Note that at the same time, the sensor 17 detects an accident and closes the contact 16.

With this roof tile, the central device 6 is placed at high voltage via the high voltage coupler 4!
When a repeater call signal C1 as shown in FIG. When the repeater 11 receives this call signal C1, it injects a signal into the overhead ground wire 6 via the detector 12 and transmits the signal as shown in FIG.
A terminal paging signal C2 such as the following is injected. This calling signal C
2 is transmitted only to the terminal device 18 whose contact point 16 is closed, that is, the terminal device 18 that is detecting an accident, and the corresponding terminal device 18
From there, a return signal R1 as shown in FIG. Therefore, the repeater 11 receives this return signal R1, and thereby returns the signal R2 as shown in FIG. At this time, the response signal includes the address information of the failure point, etc. (
If this is done, the central device 3 can know the point of failure from the response signal.

Note that the present invention can be applied not only to the power distribution system as described above, but also to a sectional switch remote control system, a power distribution automation system, and the like.

〔Effect of the invention〕

According to the present invention, by providing a repeater, a sensor, a terminal device, etc., it is possible to detect a failure point in a short time while staying at the central device.

In addition, since the fault point is searched for via the overhead ground wire, it is possible to use low voltage specifications, and as a result, the terminal unit can be made smaller.

It is possible to reduce the weight and further reduce the price.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of this invention, and FIG.
FIG. 3 is a schematic diagram showing a general example of a failed section separation device, and FIG. 4 is a time chart for explaining the operation of FIG. 3. Description of symbols 1...Distribution circuit breaker, 2...Fault section indicating device, 3...Central device, 4.7...High voltage coupler, 5... ...High voltage distribution line, 6...
Overhead ground wire, 8, 81-83...Power transformer,
9, 91-93... Sectional switch, 101-10
3...Timed control equipment, 11...Repeater, 12...Signal injection/detector, 13...
...Pole mounting equipment, 14...Archives, 15...
・Electric pole, 16... Mechanical holding contact, 17...
...C/S, 18...Terminal device. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoshi Matsuzaki If+ Figure 2 Figure C1

Claims (1)

[Claims] The distribution line is divided into designated sections, and faulty section isolation devices consisting of section switches and timed control devices are installed for each section.In the event of an accident, the substation central equipment and the faulty section isolation device operate in cooperation. In a power distribution system that is to be disconnected after the accident section, each power distribution section is equipped with a repeater that receives the call signal from the central device and injects the call signal into the overhead ground wire. A sensor is provided to detect an accident occurring in each of the sensors, and a terminal device is provided corresponding to the sensor and receives a call signal from the repeater only when an accident is detected, and returns a response signal via an overhead ground wire, A fault point detection method in a power distribution system, characterized in that a fault point is detected by transmitting a response signal from the terminal device to a central device via a repeater.