JPS6233813B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to protective relay devices and, more particularly, to an improved automatic inspection method.

Static protective relays, which are mainly composed of semiconductor components such as transistors and ICs, have lower reliability than electromagnetic protective relays, so it is necessary to check the health of the protective relay device at regular intervals to prevent malfunctions. A method of checking is adopted. In this case, as the input signal for inspection, for example, the output of a sine wave oscillator (power supply for inspection) or the like has been used for this purpose.

Also, the check of the health of the protective relay output in response to this input for inspection is performed by dedicated hardware. In such a conventional method, if an attempt is made to generate inspection signals with high accuracy and improve defect detection performance, the circuit size increases and becomes complicated, which poses problems in terms of economy and reliability. Recently, as a method to overcome the drawbacks of such methods,
Adopting a microcomputer in automatic inspection equipment,
Digital signals corresponding to the sine wave signals at each point in time when the sine wave signals are divided into appropriate time segments are stored in the digital memory, and these are used in correspondence with the input signals depending on the inspection content. However, since these methods also include dedicated hardware (such as a microcomputer) as an inspection device, they have problems in terms of economy and reliability.

An object of the present invention is to overcome the problems of the prior art described above and to propose an automatic inspection method for a protective relay device that is practical in terms of economy, reliability, and inspection accuracy.

In the protection relay system, the fault section selection relay element and the fault detection relay element are separate hardware in order to prevent failure of the element relay that is a component of the protection relay system from interfering with power supply. (1) When inspecting the accident section selection relay device, the accident detection relay device executes the calculation program for accident response without executing the calculation program for the accident detection relay that is always running. , to generate inspection data for the accident section selection relay.

Furthermore, check the inspection results.

(2) When inspecting the accident detection relay device, the accident section selection relay device does not execute the always running accident section selection relay calculation program, but executes the accident response program and also checks the accident detection relay. Generate inspection data for. Furthermore, check the inspection results.

That is, the accident detection relay element and the accident section selection relay element mutually check each other.
The present invention is characterized in that it overcomes the drawbacks of the prior art and achieves the above objectives.

As mentioned in the prior art, in the protection relay system, in order to prevent the power supply from being disrupted due to a malfunction of the element relay, which is a component of the protection relay system,
Conventionally, the idea has been to separate the hardware of the accident section selection relay element and the accident detection relay element. The present invention also follows this idea as it is, and here, an example in which the above-mentioned relay element is applied to a digital protection relay using a microcomputer will be described with reference to the drawings. FIG. 1 shows the block configuration of a protection relay system to which the present invention is applied. In the figure, 1 is the above-described accident detection relay element, 2 is an accident section selection relay element, 3 is an automatic inspection start timer, and 4 and 5 are input changeover switches. The present invention will be specifically described below using FIGS. 2 and 3.

First, the processing of the accident detection relay element described above will be described using FIGS. 2 and 1. The accident detection relay element (hereinafter referred to as FD) first determines whether or not the other device, that is, the accident section selection relay element (hereinafter referred to as M), is to be inspected (step 21 in Figure 1). It is determined whether the timer output signal line A is at level 1.When M inspects, signal line A is at level 1). If M is not an inspection, the process advances to step 10 and a predetermined accident detection relay calculation is executed. Then, the process proceeds to step 11, where the calculation result is compared with a predetermined constant value to determine whether an accident has occurred. If it is determined in step 11 that an accident has occurred, the process proceeds to step 12 and an operational output is issued via the signal line B in FIG. Further, the process proceeds to step 13, in which the output of the partner device, ie, M, is constantly monitored via the signal line C, and it is determined whether there is any abnormality in M. If there is an abnormality as a result of the judgment, the process proceeds to step 14, where the abnormality is notified and the process stops. If the determination result in step 13 is normal, the process returns to step 21, as can be seen from the figure, and the process is repeated in the same manner.

In other words, the accident detection relay element FD performs (1) calculation processing for the accident detection relay and (2) calculation processing of the accident area selection relay element when the partner device (accident section selection relay element M) is not inspected in step 21 of Fig. 2. It executes constant monitoring processing.

Next, if it is determined in step 21 of FIG. 2 that the other device, that is, the M element, is to be inspected (signal source A in FIG. 1 is at level 1), the process proceeds to step 22, and although not shown, Lock the trip command and proceed to step 23. In step 23, the FD does not execute a predetermined accident detection relay calculation, but takes accident response into consideration and executes an accident response relay calculation. In step 24, the calculation result in step 23 is compared with a predetermined constant value. As a result, if it is determined that there is no accident, the process proceeds to step 25, and the input selector switch 5 is switched to the a side (for inspection) via the signal line D in FIG. The process then proceeds to step 26, where the M inspection data is output via the signal line E. In step 27, it is determined whether a certain period of time has elapsed (using a soft timer, etc.). If the certain period of time has not elapsed, return to step 21 and repeat execution for each sample. If a certain period of time has passed in step 27,
Since the output of M corresponding to the inspection data should have been output, the process proceeds to step 28, where the result is inputted via the signal line C in FIG. 1 and judged. If the determination result is abnormal, this means that the hardware of M is defective, so the process proceeds to step 29, where it is notified that M is defective as a result of the inspection, and the process is stopped. step
If the inspection result is determined to be normal in step 28, proceed to step 15, connect the input selector switch 5 to the b side (input to system information) via the signal line D, and
Release the shunt command locked in step 22 and return to step 21. Thereafter, exactly the same processing is repeated. That is, the accident detection relay element FD is
When the other device (accident section selection relay element M) is determined to be inspected in step 21 of Fig. 2, (1) Calculation processing for accident response (2) Output processing of inspection data to accident section selection relay element M ( 3) Executes output check processing for inspection data.

The above explanation is based on the accident detection relay element 1 in Fig. 1.
The processing of the accident section selection relay element 2 is exactly the same (in the case of the accident section selection relay element, the signal lines A to E described in the accident detection relay element correspond to A' to E'). ).

Here, the programs that each relay element should have are: a; Self-relay calculation program; b; Accident response program during inspection of the other relay; c; Data generation program for inspection of the other relay; d; Program for checking the inspection results of the other relay. e: There are five programs for constantly monitoring the output of the other relay, and each relay element processes programs a and e at all times (when not during inspection). Also, when the partner device performs inspection, steps b, c, and d are executed.

FIG. 3 shows the above processing in chronological order, where a represents the FD process, b represents the M process, Δt represents the sampling period, t ₁ represents the start of inspection, and t ₂ represents the end of the inspection.

From the above explanation, it will be understood that mutual inspection and monitoring can be performed using only the accident detection relay element FD and the accident section selection relay element M.

Although we have not described the details of the inspection data, the inspection data may be generated according to c in Fig. 4, that is, the inspection data generation program for each sample, or, for example, during the initial processing. There are various methods, such as just deriving it in advance using the program c above and outputting it at the time of inspection.

Furthermore, in the present invention, as shown in FIG.
It goes without saying that steps d and e may also be executed.

Since the above explanation has been given using the case where each relay element is of a digital type, FIG. 6 shows the block configuration of a known digital type protection relay element. In the figure, 31 indicates an input section. Among them, 111A to 111N are analog filters (for removing harmonics), 112A to 112N are sample holders, 113 is a multiplexer, 114 is an analog-digital converter, 115 is a buffer memory, and 116 is a timing generation control circuit. Further, 32 indicates a digital processing section. this house,
121 is the CPU (central processing
unit), 122 is a ROM (read-only) that stores a program as shown in FIG.
123 is a data input/output circuit, and 124 is a random access memory (RAM) 125 for temporarily storing data. Therefore, the inspection data described above may be given as a digital quantity by switching the output of the A/D converter 114 (input of the buffer memory 115), or it may be converted into an analog quantity and sent to the analog filter. Needless to say, it may be given from the input of .

Although only the FD and M examples have been described in this embodiment, it goes without saying that the present invention can be applied as is to the field of process control comprising a plurality of digital processing devices (microcomputers).

According to the present invention, (1) Mutual automatic monitoring (automatic inspection and constant monitoring) of the accident detection relay element and the accident section selection relay element can be performed, so almost no additional hardware is required (the program capacity for self-monitoring is small). However, this increase does not necessarily lead to an increase in the amount of hardness).

(2) Therefore, it is possible to achieve a simple hardware configuration with the minimum necessary amount, and high reliability can be achieved.

(3) Therefore, the economic merits are also very large.

(4) Furthermore, since highly accurate inspection signals can be generated, defect detection performance can be improved.

The practical benefits are enormous.

[Brief explanation of the drawing]

Fig. 1 is a block configuration diagram of a protection relay system to which the present invention is applied, Fig. 2 is an operation flow diagram of each relay element, and Fig. 3 is a diagram showing the chronological processing status of a program provided in each relay element. Yes, 4th
The figure is a block diagram of a known digital protection relay element. 1... Accident detection relay, 2... Accident section selection relay, 3... Automatic inspection start timer, 4, 5...
...Input selector switch.

Claims (1)

[Claims] 1 Consisting of a plurality of protective relay devices, the system information that is constantly given to each protective relay device is switched to inspection input, and the response status to the input is examined to confirm the health or failure of the protective relay device. In the automatic inspection system for protective relay devices equipped with the system, when one protective relay device A is inspected, the other protective relay device B performs accident response processing, inspection data output processing to the protective relay device A, and An automatic inspection method for a digital protection relay device characterized by executing output check processing on inspection data.