JP3373053B2 - Protection control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection control device for a power system.
Detects intermittent defects
The present invention relates to a protection control device provided with a means for performing [0002] 2. Description of the Related Art Conventionally, protection control devices, especially power
High reliability is required for the protection control device
Have been. For example, a protective relay may malfunction
The impact is very large, and in the worst case
It is thought that it may also lead to the collapse of the religion. Also, protection relay
Not only the protection control device but also other protection control devices such as a system stabilization device,
Equipment such as the accident point locating device and the system
The responsibilities from the power system operation point of view are critical and high reliability
Is still required. As a measure for improving the reliability of these protection control devices,
Quality improvement of used parts, multiplex configuration, other series configuration
And the application of automatic monitoring.
The application is widely used in power system protection and control devices in general.
I have. On the other hand, in recent years, protection systems using microprocessors
Practical use of control equipment is progressing rapidly.
As the technique changes, so does the complexity of the device.
The automatic monitoring function is also becoming more sophisticated. [0004] A digital protection relay (hereinafter, referred to as a digital relay) will be described below.
Representative monitoring performed by digital relays)
Will be described. FIG. 5 shows a general digital relay.
It is a block diagram. In FIG. 5, the current / voltage amount of the transmission line 1
Through a current transformer (CT) 2 and a voltage transformer (PT) 3
To the input converter 4 where it is changed to a predetermined level.
Replace. [0005] The output of the input converter 4 is an analog filter.
5 to obtain a stable signal. Next, the sampling hole
The amount of current and voltage taken into the load circuit (S / H) 6 is
It is converted to a flow rate and input to the multiplexer (MPX) 7.
A for sequentially converting an analog quantity into a digital quantity
/ D converter 8. And the A / D converter 8
The digital data of current and voltage converted by
In the data memory (RAM) 9-1 in the microcomputer 9
Stored sequentially. On the other hand, the program memory (ROM) 9-2
Stores program instructions, and
Using the data in the data memory (RAM) 9-1,
The calculation is performed by the central processing unit (CPU) 9-3,
Input / output interface (I / O) for predetermined results
Output to the outside via 9-4. Digit with the above configuration
The grounding relay relays the current and electricity obtained through the input converter 4.
A plurality of protection characteristics are realized using the pressure data. Each of the digital relays
As described above, the monitoring of the hardware section is performed by the CPU 9-3
It is realized by utilizing the ability. Items to be monitored include:
For example, Electric Cooperative Research Vol. 41, No. 4, "Digital Relay"
According to page 71, each phase balance monitoring PCT circuits 2 and 3
Degree monitoring, input converter 4, analog filter 5, S / H
6. Zero-phase component monitoring for monitoring the multiplexer 7, etc.
A / D accuracy monitoring for monitoring the accuracy of the D converter 8;
DI and DO monitoring interface (I / O) 9-4
Check, read / write check to monitor RAM9-1, R
Invalid check to monitor OM9-2 (undefined instruction
Detection). [0008] By monitoring this, it is determined that a problem has occurred.
The timing of the rejection is as described on page 71 of the material.
In the case of the instantaneous case, the predetermined number of times
When a failure is judged when a monitoring failure occurs for more than a time
There is. Consider most of the monitoring target
In the latter case, the latter method is used
A continuous detection method is used. Generally, a fixed period
, The same monitoring is carried out.
The method can be said to be equivalent to the continuous detection method for a predetermined time. [0009] [0010] [0011] [0012]Conventional methodFigure is a diagram that represents the processing of
6Becomes That is, the time delay Tk on-delay timer is before
This corresponds to the monitoring failure detection timer described above. The figure6No
Delay timer can also be implemented in hardware
This is well known (the implementation method is omitted). Figure7
(A) is a time expressing the function of the monitoring failure detection timer.
It is a chart. When monitoring failure continues for Tk hours
In this case, a failure occurrence signal is output and
This indicates that the failure occurrence signal also returns. [0013] The monitoring failure detection processing conventionally performed is described above.
However, monitoring that does not occur continuously in conventional processing is not possible.
Good, that is, intermittent monitoring failures are
May not be detected. Fig.7(B)
Show. That is, a failure in which the monitoring failure does not continue for more than Tk time
Even if it occurs intermittently, it cannot be detected as a defect
Become. Conventionally, the above-described continuous detection method for a predetermined time is employed.
However, this cannot be monitored due to a single cause such as noise.
Good, which instantly determines that the equipment is defective.
And taking measures such as shutting down the operation of the equipment
It also leads to lower working rate, which is not desirable
For reasons. That is, confirmation for a predetermined period of time
One-shot failure due to noise etc.
Expected failure) and the original monitored failure (repeated
Expected to depart from)
It can be said. [0015] On the other hand, occurrence of monitoring failure
Considering the situation, failures are not always
Not continued, figure7As shown in (b), intermittent failures occur
It can be said that in some cases. In other words, the appearance of defects is mainly
Deterioration of hardware that constitutes the part to be viewed and surrounding environment
However, these causes are complicated
If it is affected, the occurrence mode, ie, frequency, interval,
It can be said that the life duration and the like are various. Therefore, the conventional method for detecting a predetermined time continuously is used.
In the formula, there is a monitoring failure that looks like there is a problem with the equipment function.
Problem that it may not be possible to judge a bug
There is. In particular, if the failure frequency is high,
If the fault is recovered within the specified time,
Equipment is in operation even though it is in a bad state for a long time
And normal operation of the equipment can be expected for a long time.
I can't say that. As a countermeasure against this, a predetermined time Tk is
There is a way to shorten it, but as mentioned earlier,
One-shot failures such as noise result in lower availability
That's not a good idea. In the above, the protection control device
Although the explanation has been given for component failures,
The same situation exists for detection. Example of failure detection outside the device
The digital relay monitors the PCT circuit described above.
Monitoring of each phase equilibrium to be monitored. This is for detecting defects such as disconnection of the PT and CT circuits.
Monitoring that is required for the protection function to work properly
It is. Therefore, failure of components inside the device and characteristics outside the device
Detecting defects in fixed parts is equally important,
Can be said to have similar problems. The present invention
Intermittent surveillance, which was made in consideration of the situation
Protection to detect faults and obtain fault output
It is intended to provide a control device. [0019] SUMMARY OF THE INVENTION A protection control device according to the present invention.
Is used to protect or control the power system
In a protection control device provided with monitoring means, the protection control device
Monitoring for detecting at least one defect of internal and external monitoring targets
A failure detection unit, and the monitoring failure detection unit detects
Observe the frequency of monitoring failures for a predetermined periodAnd its failure occurs
When determining the number of monitoring failure occurrences within the predetermined period
When the product value is A, the value of A calculated by the following equationIs prescribed
valueTkTo determine if a failure has occurred
Fault occurrence determining means, and an observation result by the determining means
ToAs a defect historyData reference means to checkWith. Record (Equation 1)[0020] [0021] [0022] [0023] The protection control device according to the present invention firstly
Is detected by a predetermined method. The resulting
The frequency of monitoring failures is monitored for a predetermined period, and the observation results are recorded.
In addition to memorizing, determine whether there is a problem and output the defect judgment
And then take measures such as alarms, displays, and device operation suspension inside and outside the device.
Will be implemented. Also, patrol the stored observation results.
Data for maintenance and operation of equipment
Use as In the protection control device according to the present invention,
Is used as a reference for the cumulative value of monitoring failures within a predetermined time
Has established a standard for the frequency of monitoring failures.
Made the decision possible. [0025] [0026] FIG. 1 shows a protection control device according to a first embodiment of the present invention.
It is a functional block diagram of one Example. In FIG. 1, 10
Is a protection control device, and the monitoring target 1 in the protection control device is
At least one or more failures of the monitoring target 2 outside the protection control device
Monitoring failure detecting means 11 for detecting goodness,
Observe the frequency of monitoring failures issued for a predetermined period, and
The results are stored, and the observation results indicate
Fault occurrence determining means 12 for determining the presence or absence of occurrence, and means 12
Data reference means 13 for confirming observation results stored by
It is composed of The specific hardware configuration is
Equivalent to the standard digital relay shown in Figure 5 above
Yes, and the description is omitted. The function is realized by R in FIG.
Execute the program stored in OM9-2 on CPU9-3
It is achieved by doing. The feature of the present invention is that
Intermittent was impossible to determine as a failure
The point is that the good mode can be detected. For this purpose, the above-described malfunction occurrence determination means 12
Is provided with the function shown in equation (1). (Equation 2)Equation (1) shows that during the observation period,
The cumulative value A of the monitoring failure occurrence frequency calculated by the formula is predetermined
If the value exceeds the determination value Tk, it is determined that a problem has occurred.
It indicates that you want to. In the equation (1), D is the value of the monitoring failure detecting means 11 described above.
As a result of executing the program processing, it is
In this case, the maximum amplitude of the data to be added to the accumulated value A is displayed.
Predetermined constant, T indicates a predetermined predetermined decay time constant.
ing. Equation (1) is shown on a graph as shown in FIG.
Become. In FIG. 2, the horizontal axis represents the presence / absence of monitoring failure.
Is the time axis showing the time series, and the vertical axis shows the occurrence of monitoring failure.
This is the cumulative value A of the frequency. In this graph,
, The cumulative value A increases by a predetermined value D,
Monitoring failureNo occurrenceIs detected, the continuous return
The damping characteristic realized by the exponential function term of equation (1) according to the width
Therefore, the data is subtracted from the accumulated value A. [0030]It is realized by the exponential function term of the above equation (1)
Curve is poorly monitoredNo occurrenceWhen the state continues for infinite time
In this case, the maximum attenuation value is suppressed to the predetermined value D.
This means that if a monitoring failure is detected even once,
This shows a feature that a failure history is left. Next, the book
The operation of the invention will be described. The advantage of the present invention is that
Even if the failure frequency is low, past failure histories will always accumulate.
That is. In other words, even the continuity of the defect
If any, regardless of the frequency of occurrence, it will always occur as a defect someday
It is possible to see. FIG. 3 is a characteristic diagram showing an embodiment of the protection control device.
It is. In the embodiment in which the above-described equation (1) is used as the principle equation,
The use of mathematical function terms as principle
Even if the frequency of occurrence is poor, there is no
The feature is that it can be found as a defect
did. However, in reality it is too infrequent
It is not necessary to catch all the defects
Can be virtually ignored in consideration of the service life of
May be considered. In addition, the exponential function term
And programming as it is is processing efficiency
Not a good idea. In consideration of the above, the above-described trouble occurrence determination method
The function shown in the expression (2) is provided as the stage 12. (Equation 3)Equation (2) provides a predetermined decay time constant T,
Cumulative value A decreases monotonously during the period of time tk of continuous return T
If T exceeds T, the value to be added to the cumulative value A is reduced to zero.
Indicates that Equation (2) is shown on the graph.
As shown in FIG. FIG. 3 shows the slope of the attenuation characteristic portion of FIG.
2 except that it was approximated by a straight line of -D / T.
You. FIG. 4 shows an embodiment in which the functions of FIG. 3 are realized by a program.
This will be described with reference to the flowchart of FIG. First, in step S2-1 (hereinafter, “s
Start this program with [Step] omitted, and in S2-2
Initialize the accumulation counter A and the attenuation counter B. Next
Next, the monitoring failure is detected in S2-3. This processing is shown in FIG.
Equivalent to monitoring failure detection means 11I do.Next, monitoring failure in S2-4
Judgment of presence / absence of detection.
The value of the subtraction counter B is added and stored.
The upper limit value D is stored in the counter B, and the process proceeds to S2-13. On the other hand, if no monitoring failure is detected, it is disabled in S2-7.
The presence or absence of the combined output is determined. If there is no output, go to S2-10.
In 2-8, it is further determined whether or not the display is restored.
To the accumulation counter A and the decrement counter in S2-9
Initialize B. In S2-10, a predetermined value is obtained from the subtraction counter B.
Subtract d. In S2-11, the sign of the subtraction counter B is determined.
Then, if it is positive, go to S2-13, if it is negative, decrement the counter B by S2-12.
Zero clamp. Next, at S2-13, the value of the cumulative counter A is checked.
If the value exceeds the fixed value Tk, a failure output “Yes” is given in S2-14.
Then, the clamp value Tk is stored in the accumulation counter A in S2-15.
Then, a standby state is set in S2-17. On the other hand, the accumulation counter A
If the value is less than the predetermined value Tk, a failure output "Nothing" is made in S2-16.
Then, at S2-17, a standby state is set. The above is the program of the present invention.
This is one processing of the system. S2-3 to S2-17 at regular intervals
The function of equation (2) can be realized by repeatedly calculating with. Next, the operation of this embodiment will be described. No monitoring
If goodness occurs intermittently, the conventional method
What could not be caught as shown in Figure 3
As described above, according to the above embodiment, the monitoring failure during the observation period
If the cumulative value A of the occurrence frequency exceeds the predetermined judgment value Tk, it is disabled.
Is determined to have occurred, so that abnormal phenomena can be reliably detected.
It becomes possible to receive. In the above embodiment, the cumulative value during the observation period
If A exceeds a predetermined determination value Tk, it is determined that a malfunction has occurred.
Although the frequency of failure occurrence is lower,
Occurrence of an event in which the accumulated value A does not exceed the predetermined judgment value Tk
Is also conceivable. This event itself is immediately a defect
Not before, but depending on the situation of adding the cumulative value A
Considering that it is good to recognize it as a sign and take appropriate measures
available. An embodiment of the present invention for this event (claim
1) will be described below. In this embodiment, the fault occurrence determining means 12
Cumulative value of monitoring failure occurrence frequency during the stored observation period
Data to confirm A as needed during patrols, periodic inspections, etc.
Data reference means 13 is provided. In this embodiment, FIG.
As shown in the graph and the graph of FIG.
Configuration to ensure that failed history remains as accumulated value data
This data can be referred to as needed.
Noh. The data reference means 13 is not particularly limited.
However, in general, the following methods are considered.
It is. Direct reading method of internal memory: Normal digital
Internal memory (random access memory)
The observation LED for observing the state of
It is provided on the board, for software debugging and internal
Used for memory observation. The display format is binary or tens.
Although it is displayed in hexadecimal and there are parts that are difficult to read, the cumulative value
It can be used as a data reference means. Reading method from external display: Normal data
For digital protection relays, refer to the set value of the relay element.
Refer to the current set value when referencing or changing
LED display as an external display function to enable
Indicators (decimal notation is common) must be provided
It's a book. Use this display function to
Easy to refer to accumulated value data if used as a reference
It is feasible. Storage method in magnetic memory: Internal memory
(Random access memory) Many states at a certain moment
As a recording means, there is a method using a magnetic memory.
One-touch insertion magnetic memory cassette (commonly known as bubble cassette)
) To periodically write cumulative value data.
The method will be used. To refer to accumulated value data
Remove the magnetic memory cassette and check the memory contents
Is achieved by How to read with internal memory analysis tool
Equation; Internal memo in modern digital protection relay
Analysis tools that refer to the data in real time have been developed.
You. This is the common bus for the CPU board (commonly known as the system bus)
Insert a dedicated CPU board for analysis above and transfer the data on the bus.
Observes and stores the observation data in non-volatile memory (commonly known as E^TwoPRO
M) and store the contents of the non-volatile memory as necessary.
It is a method to draw out. Observe cumulative value data with analysis tool
By setting as data, reference of accumulated value data
Is easily realizable. Printer printing method of internal memory: protection
For response analysis or regular operation during ray operation or failure occurrence
Printer print function for checking the relay internal data
Data in accordance with a predetermined print format.
There are digital protection relays that are designed to print.
In such a case, the accumulated value data is
If you assign a launch of
It can be easily realized. The data reference means described above is a digital
In the field of protection and control devices
Any means are considered very common
May be. Next, the operation of the present embodiment will be described. Monitoring failure
It occurs intermittently, and its frequency is
Is a very low event,
Because we were able to observe the status of good occurrence,
It is possible to grasp in advance the signs of problems inherent in the equipment
It works. [0046] As described above, according to the present invention, the monitoring
Observe the frequency of poor vision for a predetermined period, and consider the frequency of occurrence.
To determine the occurrence of a problem
Intermittent failures that were difficult to find with the device
Detects and outputs external alarms and displays and equipment according to the detection results
It is possible to guide the operation to stop the operation. Also, bad shoes
Since the principle of history accumulation is applied, continuous defects
Therefore, regardless of the frequency of occurrence, it is always
Can be discovered. In addition, the prescribed
The frequency of monitoring failures is lower than the
According to the present invention, even if the
Since the occurrence status is configured to remain as a memory,
Check the data at the time of periodic inspection,
It is easy to grasp and take appropriate measures. these
Based on this, the present invention requires extremely high social reliability.
Demonstrates its performance in the required protection control device
Protection with monitoring measures considered to be very effective
A control device can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a functional block diagram of one embodiment of a protection control device according to claim 1 of the present invention. FIG. 2 is a line graph illustrating the basic principle of the present invention. FIG. 3 is a line graph illustrating an example of the present invention. FIG. 4 is a flowchart illustrating processing contents according to the embodiment of the present invention. FIG. 5 is a configuration example diagram of a conventional protection control device. FIG. 6 is a logic circuit diagram showing a conventional method. FIG. 7 is a time chart for explaining the response of the conventional method.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuo Ueno 1 Toshiba-cho, Fuchu-shi, Tokyo Inside the Toshiba Fuchu factory (72) Inventor Takayuki Yokoyama 1 Toshiba-cho, Fuchu-shi, Tokyo Fuchu Toshiba Inside the factory (56) References JP-A-2-70221 (JP, A) JP-A-2-246726 (JP, A) JP-A-3-11916 (JP, A) (58) Fields studied (Int. . ^7, DB name) H02H 3/00 - 3/07

Claims (1)

(57) [Claim 1] In a protection control device provided with monitoring means used for protecting or controlling a power system, at least one defect of a monitoring target inside and outside the protection control device is detected. Monitoring failure detection means, and monitoring the occurrence frequency of the monitoring failure detected by the monitoring failure detection means for a predetermined period ,
When judging the occurrence of a condition, monitoring
When the cumulative value of good occurrence is A, the value of A calculated by the following equation
And defect occurrence determination means value to determine the presence or absence of defects caused by whether exceeds a predetermined value Tk, the protection control, characterized in that a data reference means for confirming observations by the determining means as bad history apparatus. Note [Equation 1]