JPS61106019A - Digital circuit selective relay device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital line selection relay device.

[Conventional technology]

Generally, 154KV is used as a relay device to protect the power system.
Relaying devices for high-resistance grounding systems (double-circuit transmission lines) of the following types use line selection relays for main protection and directional distance relays for back-up protection. This is because the main protection is required to have the ability to select a faulty line, and the backup protection is required to have the safety of eliminating faults.

FIG. 3 is a block diagram showing the system configuration of a conventional device shown in, for example, Tokyo Electric Power Co., Digital Line Selection Relay Device, Standard Specification Moss, P-6, July 1980. In the figure, reference numeral 1 denotes a line selection relay which administers the main protection of the power system, and numeral 2 denotes a directional distance relay which administers the backup protection of the power system.

Next, the operation will be explained. When the line selection relay 1 and the directional distance relay 2 detect that an accident has occurred in the power system, a trip command 6 is outputted by the logical sum of their outputs, and the power system is freed from the accident.

[Problem that the invention seeks to solve]

Since the conventional digital line selection relay device is configured as described above, the distance direction protection relay may become defective.
'If it is not possible to protect the suspension power system, it will be necessary to stop the power transmission of the faulty transmission line and operate the system to superimpose the power flow on other lines, and the loads connected to the line for which power transmission has been stopped will be affected by a power outage. There were some problems, such as:

This invention was made in order to solve the problems of the conventional ones as described above, and it is possible to protect the power system without stopping power transmission on the relevant power transmission line even if the directional distance relay for backup protection becomes defective. An object of the present invention is to provide a digital line selection relay device that can enhance functionality.

[Means for solving problems]

The digital line selection device according to the present invention includes a main protection function circuit that performs main protection of an electric power system, a backup function circuit that maintains backup of the power system, and a backup function circuit that responds to activation of a fault signal and controls the main protection function circuit of the power system. A line selection relay having a function selection circuit that stops operation and operates the backup function circuit, and a line selection relay that has a function of backup protection of the power system and energizes the failure signal when a failure of this function is detected. and a directional distance relay having a detection circuit.

[Effect]

The function selection circuit operates the main protection function circuit when the faulty signal is not activated, and when the faulty signal is activated, it operates all the backup protection function circuits in place of the main hold function circuit. To maintain and protect a power system without performing an operation to stop power transmission to be protected even when a directional distance relay becomes defective.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 4 denotes a detection circuit for detecting a defect in the backup protection function of the directional distance relay 2, which activates a defect signal 5 when the defect is detected.

6 is a function selection circuit that selects a function based on the defective signal 5;
8 is a main protection function circuit that controls the main protection function, and 8 is a backup protection function circuit that controls the backup protection function.

Next, the operation will be explained with reference to the flowchart shown in FIG. When the directional distance relay 2 is normally performing its backup protection function, the detection circuit 4 does not energize the fault signal. In such a state, step S1 is NO.
Therefore, in step S2, the function selection circuit 6 switches to the main protection m
function circuit 7 is selected and all of them are operated. That is, the line selection relay 1 is performing the main protection function.

However, in step S1, the detection circuit 4 detects the direction distance relay 2
When a defect is detected in the backup protection function, the defective equalizer is activated, and step S1 becomes negative, and the result becomes X (Yes). Therefore, the function selection circuit 6 executes step 86 to select the backup protection function circuit 8 and operate it. Through this operation, the digital line selection relay device becomes capable of protecting the next line and being able to cope with a same-name phase accident that spans two lines.

In the above embodiment, the line selection relay device has been explained to the fullest extent, but other relay devices having different hardware for primary protection and back-up protection may be used, and the same effects as in the above embodiment can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, the line selection relay having the main protection function is equipped with the 11th backup protection circuit, and when a defect is detected in the directional distance relay having the backup protection, the backup protection function circuit is activated. By doing so, even in the event of a failure of the directional distance relay, a full backup protection function can be ensured, so the function as a protection device can be enhanced, and the reliability of the power system can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a digital line selection relay device according to an embodiment of the present invention, FIG. 2 is a flowchart of the operation of the relay device shown in FIG. 1, and FIG. 3 is a conventional digital line selection relay device. FIG. 1 is a line selection relay, 2 is a directional distance relay, 4 is a detection circuit, 6 is a function selection circuit, 7 is a main protection 8A function circuit, and 8 is a backup protection function circuit. Note that the same reference numerals in the figures indicate the same or similar parts.

Claims (1)

[Claims] A directional distance relay having a function of providing backup protection for an electric power system and having a detection circuit for detecting a failure of this function;
Stopping the operation of the main protection function circuit upon detection of a failure in the main protection function circuit that provides main protection of the power system, the backup function circuit that provides backup protection of the power system, and the detection circuit;
A digital line selection relay device comprising: a line selection relay having a function selection circuit for operating the backup function circuit.