KR101087869B1 - Self diagnosis method for preventing mal-operation in ied - Google Patents

Abstract

The present invention relates to a self-diagnosis method for preventing a malfunction of a protection relay. The present invention relates to an initialization step of writing and initializing predetermined values in at least one temporary address of a memory, and reading data stored in one of the temporary addresses. And a comparison step of comparing the read data with a predetermined setting value, and a determination step of determining and processing as a data error when the read data and the predetermined setting value are not the same.

Protection Relay, Memory, Microprocessor, Error, Lead / Write

Description

Self-diagnosis method to prevent malfunction of protection relay {SELF DIAGNOSIS METHOD FOR PREVENTING MAL-OPERATION IN IED}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective relay (IED), and more particularly to a self-diagnosis method for preventing a malfunction of a protection relay for preventing a malfunction between a memory and a data bus in the protection relay.

Self-diagnosis is a technology necessary to enhance the safety of devices such as digital protective relays, PMUs, and measuring instruments that require contacts.

Self-diagnosis is applied to prevent the malfunction of equipment. It is mainly done in power supply, AD converter, memory (RAM), set value, etc. In case of memory, it is difficult to always monitor and requires fast operation because it takes a lot of time. Even with the self-diagnosis function, it is difficult to prevent malfunction.

The present invention can prevent the malfunction of the protection relay by preventing the malfunction of the device by simply and constantly monitoring the error of the data bus due to the external memory and the intrusion of noise, the error of the microprocessor, etc., which controls the data communication. It is to provide a self-diagnosis method.

Technical problems to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. There will be.

Self-diagnosis method for preventing the malfunction of the protection relay of the present invention for achieving the above object, the initialization step of writing to each of the predetermined predetermined value to at least one temporary address of the memory; A comparison step of reading data stored in the one temporary address and comparing the read data with a predetermined set value; And a determination step of determining and processing as a data error if the data read above and the predetermined value are not the same.

Specifically, the temporary address is at least two, characterized in that the comparison step and the determination step is repeatedly performed until the comparison between the data stored in each of the plurality of temporary addresses and a predetermined set value is completed.

The temporary address may be located at the front and rear ends of the addresses in which the main variables are stored.

As described above, the present invention reads the memory diagnostic check variables located at the beginning and the end of the main data, and if the variable is not a predetermined variable, treats it as an error, thereby making it very simple to check the health of the memory and the data bus.

In addition, since the added new check variable is only read and not written, the stability of the data is ensured, and the self-diagnosis process is performed just before the important determination, thereby ensuring more stable operation.

As described above, since the health of the memory and the data bus can be confirmed with a plurality of fixed check variables, data can be processed at high speed and have a constant speed regardless of the number of main data.

6, when there is a large amount of main data or when higher reliability is required, two or more check variables may be used to diagnose the health of the memory and the data bus.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. Like elements in the figures are denoted by the same reference numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

FIG. 1 is a schematic block diagram showing a main portion of a general digital protection relay, and includes a memory 10 (RAM), an AD converter 20, a microprocessor 30, a backplane controller 40, and a DPRAM 50; Dual Port Random Access Memory, and an external PLC (Programmable Logic Controller) 90 are included.

Each of the devices 10 to 50 is connected to each other through a data bus 1 to transmit and receive data. When the error occurs in the system configured as described above, there may be an error that the data bus is shaken due to the FG's unconnected or incorrect wiring, and the main variables such as the memory 10 (RAM), the backplane controller 40, and the DPRAM 50 are changed. Peripheral devices that are stored and replaced may be defective or damaged during operation. In other words, if a problem occurs in any one of the devices, the protection relay performs an abnormal operation and is very likely to malfunction.

Here, the memory 10 (RAM) is composed of an address and data (variables) as shown in FIG. 2, and variables (Variables) used for program and determination are stored at a specific address. However, there is a high possibility that a malfunction may occur when noise beyond the range that hardware can withstand on the data bus 1 or when the memory 10 is damaged.

3 is a flowchart illustrating a self-diagnosis process of the conventional memory 10 and the data bus 1, and is a self-diagnosis process used to monitor such a problem (error).

Move the value of the nth address where the main variable is stored (n is the address where the main variable is stored) to a temporary variable, write the value (PreDef1) pre-specified at the corresponding address, and read it back into the temporary variable and save it. (S1).

The value read from the temporary variable is compared with a predetermined value by comparing with each other (S2). Here, when the read value is the same as the predetermined value, another value (PreDef2) previously written to the corresponding address is written and read again, and if the read value is the same, the original data is restored to the corresponding address (S3 to S5). .

Of course, if the value read above and the predetermined value is different, it is treated as an error (S8).

This procedure is performed as many as the number of main variables (S6 ~ S7).

That is, in the past, the data of the address where the main variable is stored is stored in the temporary variable, and the predetermined value is stored in the address, and then the data of the address is read as the temporary variable, and the value read in the temporary variable is determined in advance. Otherwise it will be treated as an error.

This method of self-diagnosis must pre-define an address that temporarily stores major variables, or else it can invade the space where the program is stored and cause a serious error in the device.

In addition, when the number of major variables increases, the processing time of the program also increases, and may cause an operation time delay such as instantaneous elements requiring high speed operation, which may adversely affect the performance of the device itself.

Since such a diagnostic method requires a lot of time, there is a problem of additional price increase by using the high speed microprocessor 30, which may not be suitable for low cost products.

4 is a flowchart illustrating a self-diagnosis process of a memory and a data bus of a protection relay according to an embodiment of the present invention, which will be described with reference to FIGS. 1, 5, and 6.

First, Figure 5 shows the structure of the memory 10 when a new variable is added to the front and rear of the main variable according to the present invention.

In the present invention, for the self-diagnosis of the memory 10 and the data bus 1, check variables MemCheck Var1 and MemCheck Var2 are added to predetermined addresses (0020c570 and 0020cxxc) as shown in FIG.

Temporary addresses (0020c570, 0020cxxc) and check variables (MemCheck Var1, MemCheck Var2) have been added at the front and rear of the main variables (Important Variables1 ~ Important Variablesxx) to check the health of memory 10 and data bus (1). , The main variables (Important Variables1 ~ Important Variablesxx) are placed between the added check variables.

In the check variables MemCheck Var1 and MemCheck Var2 of the at least one temporary address of the memory 10 configured as described above, the microprocessor 30 writes predetermined values PreDef1 and PreDef2, respectively, via the data bus 1. Initialize by writing (S11).

Subsequently, the microprocessor 30 reads the data PreDef1 stored in the first temporary address 0020c570 as the first temporary variable to compare whether the first temporary variable is equal to the first predetermined value PreDef1. (S12, S13).

If the read first temporary variable is not the same as the first predetermined value, the microprocessor 30 processes the data error (S16). Here, if there is no abnormality in the process of initializing and reading the set value in the temporary address of the memory 10, the data stored in the first temporary address and the first predetermined value PreDef1 are identical.

Meanwhile, in S13, when the read first temporary variable is the same as a first predetermined value, the microprocessor 30 stores the data PreDef2 stored in the second temporary address 0020cxxc as a second temporary. A variable is read to compare whether or not the second temporary variable is equal to a second predetermined value PreDef2.

In step S15, when the read-out second temporary variable is not the same as the second predetermined value, the microprocessor 30 processes the data error (S16).

In other words, the present invention compares whether a predetermined variable is equal to a stored value and compares it with an error if it is not the same.

If there are a large number of key variables, it is preferable to add check variables (MemCheck Var1, MemCheck Var2, and MemCheck Var3) in the front, rear, and middle of the main variables as shown in FIG. 6, in which case any one of the plurality of check variables If it is different from the predefined value, it is treated as an error.

Therefore, in the present invention, it is very simple to check the health of the memory 10 and the data bus 1 by reading the memory diagnostic check variables located at the beginning and the end of the main data and treating them as errors when the variables are not predetermined. have.

In addition, since the added new check variable is only read and not written, the stability of the data is ensured, and the self-diagnosis process is performed just before the important determination, thereby ensuring more stable operation.

As described above, since the health of the memory and the data bus can be confirmed with a plurality of fixed check variables, data can be processed at high speed and have a constant speed regardless of the number of main data.

6, when there is a large amount of main data or when higher reliability is required, two or more check variables may be used to diagnose the health of the memory and the data bus.

The present invention has been described with reference to the preferred embodiments, and those skilled in the art to which the present invention pertains to the detailed description of the present invention and other forms of embodiments within the essential technical scope of the present invention. Could be. Here, the essential technical scope of the present invention is shown in the claims, and all differences within the equivalent range will be construed as being included in the present invention.

1 is a schematic diagram illustrating main parts of a general digital protective relay.

2 is a diagram illustrating a general memory structure.

3 is a flowchart illustrating a memory self-diagnosis process according to the related art.

4 is a flowchart illustrating a memory self-diagnosis process according to the present invention.

5 and 6 are diagrams each illustrating a memory structure according to an embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1: data bus 10: memory

30: microprocessor

Claims (4)

Configuring at least two temporary addresses at fixed locations in memory; An initialization step of writing and initializing predetermined values respectively set in at least two temporary addresses of the memory; A comparison step of reading data stored in the one temporary address and comparing the read data with a predetermined set value; And A determination step of determining and processing as a data error when the data read above and the predetermined set value are not the same; Each of the two temporary addresses of the at least two temporary addresses is located at the front and the rear of the addresses in which the main variables are stored, and the data stored in the at least two temporary addresses are read-only, for the self-diagnosis of the protection relay. Way. The method of claim 1, And repeating the comparison step and the determination step until all comparisons of the data stored in each of the at least two temporary addresses with a predetermined set value are completed. delete The method of claim 1, And the temporary address is additionally located in the middle of addresses at which main variables are stored.

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