JPH01255427A - Digital protective relay - Google Patents

Abstract

PURPOSE:To prevent the output of error trip command from being generated even if a relay section is run away, by confirming that a relay section on one side is normal, and by inspecting a relay section on the other side. CONSTITUTION:In a main relay section A1, an electricity quantity is converted to a digital quantity by an input converter 1 and an A/D converter circuit 2, and by a relay arithmetic circuit 3, the internal and external sections of an accident point are discriminated. Also in an FD relay section A2, the almost same processing as that in the main relay section A1 is executed. When inspection start command is generated from an inspection start circuit 4, then by a main relay inspection controlling circuit 5, an auxiliary relay 11 is worked, and a trip circuit A3 is opened, and a trip is locked, and the main relay section is inspected. When everything is normal, then signal is fed to the FD relay section, and by an FD relay inspection controlling circuit 9, the FD relay section is inspected.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention provides a trip command to a circuit breaker under the AND condition of the operating outputs of both the main relay section and the FD relay section. This invention relates to a digital protective relay device with a diagnostic function.

(Prior art) In a protective relay device, the main relay section and the FD relay section generally have separate circuit configurations, and by setting the operation outputs of each to an AND configuration, a fault in either circuit will immediately cause a circuit breaker to be activated. It is designed so that it will not be tied to a trip command.

That is, it can be said that the main relay section and the FD relay section have a rough relationship.

In the case of inspection, either the main relay section or the FD relay section assumes the position of controlling the inspection, outputs inspection commands, and judges the results in inspection steps divided for each inspection item.

If the main relay section is in the position of controlling the inspection, when the inspection of the main relay section is completed, an inspection command is given to the FD relay section, and the inspection is carried out in series from the main relay section to the FD relay section. Fig. 4 shows an example of inspection steps. When the FD relay section receives an inspection command, the inspection items for the FD relay section,
That is, an analog input check and an output circuit check that outputs an FD relay operation command are performed.

If the main relay section is executing the program processing normally, there is no problem, but if the main relay section is out of control for some reason, the main relay section will output an operation command to itself. Additionally, it is conceivable to output an FD inspection command to the FD relay section.

(Problem to be Solved by the Invention) Conventionally, when the main relay section is out of control, it cannot be expected that the inspection start conditions such as trip lock will be checked, and when the main relay section is not checked for trip lock, the main relay The FD relay will operate and a trip command will be output to the circuit breaker.

Therefore, an object of the present invention is to provide a digital protective relay bag that will not output an erroneous trip command even if the main relay section goes out of control.

[Structure of the invention]

(Means for Solving the Problems) A digital protective relay device of the present invention includes a passage point confirmation circuit and a signal transmission circuit in the main relay section.

On the other hand, the FD relay section is equipped with a main relay monitoring circuit.

After confirming that the main relay section normally processes the program and passes several preset passing points I~, the signal transmission circuit transmits a certain signal to the FD relay section.

On the other hand, the FD relay section monitors whether the main relay section is in a normal program processing state by the main relay monitoring circuit,
When a runaway of the main relay section is detected, various commands from the main relay section are locked to prevent the FD relay section from being affected by the runaway main relay section.

(Function) In the program that makes up the main relay section, several points are set to be passed each time. (See FIG. 3) By passing all the points, the main relay section judges that it is in a state where it can normally process the program, and transmits a signal that changes each time to the FD relay section.

The FD relay section detects changes in the transmitted signal, confirms that the main relay section is in a normal state, and receives and issues various commands from the main relay section.

Thereby, it is possible to reliably prevent a mode in which the main relay section malfunctions due to the influence of the main relay section (1) when the main relay section goes out of control.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the inspection control is performed by the main relay section, but even in the reverse case, the main relay section and the FI relay section may be interchanged. In the present invention, the FD relay unit unconditionally accepts the inspection command from the main relay unit and the FD
Instead of the conventional method of outputting the first operation command, the i-'D relay section confirms that the first section is in a state where it can normally process the program, and sends a signal that changes each time (each processing routine) to the i-'D relay section. to communicate.

The FD relay section detects the change in the signal to confirm that the main relay section is normal, and receives and receives commands from the main relay section. This makes it possible to reliably prevent output of erroneous operation commands even if the main relay section goes out of control.

FIG. 1 is a block diagram of a digital protection relay device of the present invention, and will be explained using FIG. 1.

The main relay section A1 receives a current amount, which is an amount of electricity from the power system, and an amount of voltage, which are sampled at predetermined intervals by an A/D conversion circuit 2 through a human power converter 1, and converted into digital amounts. .

Using this digital quantity, relay arithmetic circuit 3 determines whether the fault point is inside or outside.

Input conversion circuit 1 of FD relay section A2. A/D conversion circuit 2
．． The relay calculation circuit 3 performs almost the same processing as the main relay section.

The inspection start circuit 4 outputs an inspection start command at predetermined intervals, and if the main relay inspection control circuit 5 satisfies the inspection start conditions, an auxiliary command is output via the output control circuit IO.
- Operate 11 of 11X (for trip lock),
1-Open lip circuit A3 and start checking the main relay section.

There are several inspection items [I], but in the case of output circuit inspection, an operation command is output to 12 of auxiliary relay MX via output control circuit 10. The contact is converted into a logic signal and input to the main relay inspection control circuit to determine whether the output circuit is inspected.

When the inspection of the main relay section is completed, an inspection command is transmitted to the FD relay section. When the main relay monitoring circuit 8 of the FD relay section determines that the main relay section is normal, the FD relay inspection control circuit 9 inspects the FD relay section.

The auxiliary relay FX 13 is operated via the output control circuit 10, and its contact is used as a logic signal to determine the quality of the output circuit inspection.

In the above, the outputs of both the FD relay section and the main relay section are used as contacts, but the case of a thyristor can be handled in the same way.

FIG. 3 shows details of the 1-pass point confirmation circuit.

Program processing is started at regular intervals from a start subroutine 30, and subroutines 31 to 38 are sequentially executed. The end subroutine 39 is a subroutine that waits until the start of the next program process. The subroutine 32 is executed every time, and 33a indicates that it is executed once every three times.

That is, the first time (30, 31, 32, 33a, 34-3
9), 2nd time (30, 31, 32, 33b...39
) and execute.

For example, the passage confirmation point is subroutine 32゜34,
If the value is set to 36.38 and the count is increased every time the confirmation point is passed, it can be determined that the program processing is normal when the count reaches 4.

FIG. 2 shows details of the present invention. The passing point confirmation circuit 6 in the main relay section Al outputs a signal that changes each time for each processing routine, and is transmitted to the signal transmission circuit 7.

The flip-flop circuit 21 is set (Q=Level) via the AND circuit 20, and is transmitted via the I10 path driver circuit 26 to the FD relay section A2.

On the other hand, the output (Q) of the flip-flop passes through an inverter circuit 22 and an on-delay circuit 24 and locks an AND circuit 20. At the same time, the AND circuit 23 is utilized via the on-delay circuit 25.

When a signal is output from the passage point confirmation circuit in the next processing routine, the flip-flop circuit 21 is reset (Q=0 level) via the AND circuit 23, and the signal is passed through the ■/○ bus driver circuit 26 to the FD relay section. It is transmitted to A2.

Contrary to the previous time, the AND circuit 23 is locked and the AND circuit 20 is kept alive.

The signal transmitted to the FD relay section A2 is sent to the buffer circuit 2.
7, one passes through the on-delay circuit 2B, and the other goes through the OR circuit 3.
1, the other is an inverter circuit 29 and an on-delay circuit 30
The signal is transmitted to the OR circuit 31 via .

If the output of the flip-flop 21 does not change and continues for more than the timer time of the on-delay circuits 28 and 30, it is determined that the main relay monitoring is defective.

When the inspection of the main relay section A1 is completed, the main relay inspection control circuit 5 outputs an FD inspection command.

The signal is transmitted to the AND circuit 35 via the bus driver circuit 33 and the buffer circuit 34 of the FD relay section A2.

If a monitoring failure is not detected (the output of the OR circuit 31 is O level), the auxiliary relay FX13 is operated in the output control circuit 10 via the FD relay inspection control circuit 9, and inspection is performed.

On the other hand, if the main relay monitoring circuit 8 detects a monitoring failure, the AND circuit 35 is locked via the inverter circuit 32, and no inspection is performed.

〔Effect of the invention〕

As explained above, according to the present invention, the main relay section and the FD
In a digital protective relay device that is composed of relay sections and in which inspection is controlled by one of the relay sections, the inspection of one relay section is confirmed to be normal and then the other relay section is inspected. Even if the vehicle runs out of control, it is possible to prevent an erroneous trip command from being output.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of the digital protection relay device of the present invention, Fig. 2
3 shows a detailed diagram of the present invention, FIG. 3 shows an example of program processing of the passing point confirmation circuit, and FIG. 4 shows an example of inspection steps. A1... Main relay section A2... FD relay section A3
... Trip circuit 5 ... Main relay inspection control circuit 6 ... Passing point confirmation circuit 7 ... Signal transmission circuit 8 ... Main relay monitoring circuit 9
...FD Relay Inspection Control Circuit Agent Patent Attorney Nori Ken Yudo Chika Ken Daishimaru Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] In a digital protective relay device that sequentially self-inspects multiple relay units that input electricity from the power system and detect accidents, multiple passing confirmation points are set in the inspection processing program for each relay unit, and one relay unit When the inspection processing program is executed, it is determined whether the relay has passed its own passing confirmation point, and if the inspection of this relay section is completed normally, the inspection of the next relay section is started, and on the other hand, if an inspection failure is confirmed, then the inspection of the next relay section is started. A digital protective relay device characterized in that it prevents the next relay section from being inspected.