JPS6346649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display device for a digital protection relay, and more particularly, to a display device for a digital protection relay, and particularly to a display device for a digital protection relay.
The present invention relates to a display device for a digital protection relay that is implemented using a single computer.

Current protection relays using dedicated analog hardware are configured to combine the operational outputs of multiple element protection relays to detect a system fault and issue a shutdown command.

The known current technology will be explained using a step-out detection relay as an example. There are various methods of out-of-step detection relays, but in this case, the impedance locus Z seen by the relay at the time of out-of-step as shown in Fig. 1 is the element relay R1, R2, R3, R4, X in the figure.
Three areas A surrounded by 1, X2, X3, and X4,
It is detected that B and C are staying in each area for a predetermined time or more in the direction of A→B→C or C→B→A, and it is determined that synchronization has occurred. The case of an impedance locus detection type step-out detection relay (hereinafter referred to as a Z-locus type step-out detection relay) will be described.

Detection of three areas A, B, and C in this Z locus type step-out detection relay is performed as follows. That is, region A is reactance relay X3,
4. All ohm relays R1 and R3 operate (first
In the figure, the shaded side of each element relay is the operation), area B is the reactance relay
1, X2 operates, and ohm relay R3, R4
is not working, so in area C, reactance relays X3, X4, ohm relays R4, R2
It is determined that the impedance locus at the time of system step-out is included in each region because all of the regions are operating.

Figure 2 shows five systems of out-of-step detection relays for protecting one system as described above, and these relays are integrated into one board.
An example in which the number is set to 0 is shown. In the same figure, inside the Z locus type out-of-step detection relay 11 that detects out-of-step in the first power transmission line, etc., there are the aforementioned elements that can detect each area shown in FIG. 1, although not shown. Contains relays, timers, sequences, etc. necessary for step-out detection. This Z locus type relay 11
introduces the current waveform from the first power transmission line, which is the object of its own protection, through the input line 11I and the voltage waveform through the input line 11V, and when detecting step-out, the output line 1
Give a trip command from 1T to the corresponding shield disconnector,
The first power transmission line is adapted to be isolated. Further, the trip command lights up the corresponding indicator light 11L in the operation display 16 via the display signal line 11D, so that the operation status can be notified to the operator and the like.

The same goes for the other step-out detection relays 12 to 15.
It takes in current and voltage information from input lines 12I to 15I and 12V to 15V from the second to fifth protected power transmission lines, respectively, and outputs trip commands 12T to 15T when step-out is detected, and displays signal lines. Indicator lights 12L-15 via 12D-15D
Turn on L.

Recently, with the rapid progress in semiconductor technology, digital arithmetic processing devices such as microcomputers have become easily available, and digitization using these devices is also being carried out in the field of protection relays. In the case of this digital protection relay, one processing device performs detection operations equivalent to the functions of many element relays, so for example, a similar device shown in FIG. If this is to be realized, all the tasks of the Z locus type step-out relay devices 11 to 15 for each system will be processed by one digital device. In other words, in terms of the number of element relays, reactance relays X1 to X4 in FIG.
5 pieces corresponding to each of ohm relays R
There are 5 items corresponding to each of 1 to R4, total
Arithmetic processing for 40 element relays will be executed.

Similar to the operation indicator 16 described in FIG. 2 in connection with the prior art, the operation display can be performed for each out-of-step detection unit of the relevant system, so an equivalent device is installed.

However, when trying to display the operation of each element relay, in the case of current analog relays, each element relay itself constitutes a single piece of hardware and has a built-in lamp to display its own operation results. Therefore, each element relay can be easily displayed even if it is assembled on a panel as a protective relay device.
In the case of a digital protection relay in which one processing device is used to determine the operation of different element relays many times in a time-sharing manner, for example, a total of 40 new indicator lamps must be provided.

This element relay operation indicator lamp is mainly used only when measuring the characteristics of each element relay, such as during periodic inspections, so it can be used for the purpose with as few indicator lights as possible. It is also desirable that it be economical. For this reason, as is generally thought,
Set the number of elements of all relays to an appropriate number (in the above example, N =
5), the display is divided into groups, and the common indicator lamps (eight in the above example) are selectively switched and displayed for each group. An example of this is shown in FIG.

In FIG. 3, BPU indicates an arithmetic processing section such as a microprocessor, ROM indicates a storage section of a program memory, and RAM indicates a storage section for data, operation results, etc. These are the core of the digital protection relay, and each has a data bus, DBUS,
They are connected via the address bus ABUS.

These buses DBUS and ABUS are further provided with information for the AD converter AD, the general operation display 26, the trip command output interface 27, and the switch SW that controls the N-way selection designation mechanism (N=5 in the example shown). An input interface DI and an element relay operation indicator 28 are connected.

On the other hand, the AD converter AD is connected to the analog multiplexer MPX, and this multiplexer MPX
System information input in a time-sharing manner via
It performs AD conversion and stores the converted data in its own internal buffer register until AD conversion is performed for the next sample.

The analog multiplexer MPX receives as input signals the outputs of data samplers 21IF to 25IF (for current information) and 21VF to 25VF (for voltage information) in which analog filters and sample holders are connected in series. These data samplers receive timing commands from an AD control unit (not shown), and all input lines 2 at the same time at every sampling time.
1I~25L (for current information) and 21V~25
It functions to sample the relevant system information via V (voltage information) and hold it until the next command is received.

The operation of the digital type step-out detection relay 20 shown in FIG. 3 as described above is performed as follows.

In the program memory ROM, a program for performing the function of the step-out detection relay is broken down into small steps and stored in order starting from a predetermined address. The program address indicated on the program counter in the arithmetic processing unit BPU is the address bus.
When given to ABUS, the program memory ROM
The instruction word is read from the corresponding address, and the data bus
It is transferred to the accumulator inside the arithmetic processing unit BPU via DBUS. The arithmetic processing unit BPU decodes this instruction word, executes the instruction based on the decoding result,
The work of this step is finished. At this time, the program counter is incremented by +1, so by giving this to the address bus ABUS, the next step is read and executed in the same manner as above.
Thereafter, the instructions of each step are read, decoded, and executed one after another, and the operations necessary for the step-out detection relay are executed.

An example of a program stored in the program memory ROM is shown in the flowchart of FIG. In the figure, a sampling end notification flag issued by hardware is referred to in step 31, and when this flag is input, in the next step 32,
System information data (current data of each system from the 1st system to the 5th system,
(voltage data) and stores it at the corresponding address in the data memory RAM.

In step 331, among the data input in step 32, voltage data and current data regarding the first system are used to perform processing for detecting step-out in the first system, and if step-out is detected, "1" is written in the corresponding position of the first system of the step-out detection information storage table, and "0" is written in the normal state when no step-out is detected.

Hereinafter, in steps 332 to 335, the same calculation process as step 331 is performed for each of the second to fifth systems, and as a result, the step-out detection information is placed in the corresponding position of the second to fifth systems in the step-out detection information storage table. Write “1” or “0” depending on the presence or absence of

In the subsequent step 34, the results determined by the processing in steps 32 to 335 are confirmed by referring to the step-out detection information storage table, and the trip command output interface 27 shown in FIG. The trip command is edited to match the trip command correspondence for each line and output processing is performed. In step 35, the general operation display 26 shown in FIG.
Processing is performed to display the same display as the current relay (display on the comprehensive operation display 16 in FIG. 2).

In each step described above, the basic function as a step-out detection relay can be achieved, but in addition, in step 36, the element relay operation indicator 28 shared by the first to fifth step-out detection relays is displayed. , select which out-of-step detection relay to use, and select the switch for that purpose.
Take in the SW information via the relevant interface DI and make a decision. In step 37, the step-out detection information storage table stored in the determinations in steps 331 to 335 described above is referred to, and the operation results of each element relay of the corresponding step-out detection relay are retrieved and stored in the element relay display table. At the same time, the contents of the table are output in a form compatible with the correspondence to each indicator light of the element relay operation indicator 28. Step 38 is a step for determining whether to repeat the above operations or to stop them.

In this way, in terms of processing operation, by adding the element relay indicator light control means in steps 36 and 37, it becomes possible to selectively display the element relays described above.

However, when the operation indicator light 28 of the element relays is shared as described above, what is displayed on the general operation display 26 when step-out is detected is the relay that detected the step-out at that time, and the element relay operation display is Since the device 28 is selected and designated by the changeover switch SW at that time, there may be cases where the two displays do not necessarily correspond to each other. For example, the selection switch SW is specified as
If the element relay operation display for the third system is selected, but step-out actually occurs in the third system, the two displays will not match.

In such a case, if the substation operator is calm, he or she should first check that the indicator light 23L for relay operation for the third system is lit on the general operation display 26, and then make a selection. SW is switched from the current designation 1 to 3 for the third system, and after this time, the operation of the element relays that constitute the step-out detection relay for the third system is displayed on the element relay display 28. Understand and be able to implement. However, imposing such judgment and operation on operators is
This is an undesirable drawback from the viewpoint of deterioration in operability and possibility of erroneous operation.

An object of the present invention is to eliminate the drawbacks of the prior art described above, and when any step-out detection relay (out of the first to fifth in the above example) operates, the element relay display 28 also To provide a display device for a digital protection relay that can automatically display the operating status of an element relay that has operated.

Furthermore, in the present invention, when a complex step-out phenomenon occurs in the system and a plurality of step-out detection relays in the relay device operate, the order in which the step-out detection is detected can also be displayed. A display device for a digital protection relay that can contribute to analysis is disclosed.

Furthermore, in the present invention, by making it possible to display whether the Z locus of the detected step-out was a clockwise locus or a counterclockwise locus, a digital system that can contribute to system analysis in this aspect is also provided. A protective relay display device is disclosed.

In order to achieve the above object, the present invention has a function that automatically selects the step-out detection relay that operates first and displays the operating status of each element relay, and a function that automatically selects the step-out detection relay that operates first and displays the operating status of each element relay. The present invention is characterized in that the processing device and the display means have a function of detecting and displaying the operating order and a function of detecting and displaying the rotational direction of the Z locus of the operated step-out detection relay.

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 5 is a block diagram showing one embodiment of the present invention, and the same reference numerals as those in FIG.
Assume that they are made of exactly the same thing. Newly added are the out-of-step relay operation indicator lights 21L to 25 for individual lines in the general operation indicator 261.
In addition to L, operation order indicator lights 21ND to 25ND
For example, when a plurality of out-of-step relays operate in the same time period, the detection order is displayed numerically. For example, when three step-out detection relays operate in the order of 3rd, 2nd, and 5th, 23ND
is displayed as “1”, 22ND is displayed as “2”, 25
The ND display will be "3", in this case 21ND
And there is no indication of 24ND.

In addition, the Z trajectory direction indicator light 29 is also newly added, and it includes the clockwise trajectory indicator light 91 of each relay.
R~95R and counterclockwise trajectory indicator lights 91L~95L
is provided, and when the step-out detection relay operates,
Whether the relay was on a clockwise trajectory or a counterclockwise trajectory can be indicated by lighting the indicator light depending on the detection situation.

FIG. 6 is a flowchart showing the operation of the embodiment of FIG. 5, and the same symbols as in FIG. 4 described above indicate steps that play the same role as in FIG. 4. Steps 341, 342, 351, and 3 are newly added to implement the present invention.
There are 52 4 steps.

That is, first, in step 341, the results determined in the processes of steps 32 to 335 described above are confirmed by referring to the step-out detection information storage table, and when there are a plurality of operating relays, the detection order is checked. Judgment and general operation indicator light 26
The result is displayed on the corresponding one of the motion detection order display units 21ND to 25ND within the unit 1.

In step 342, the operation status is similarly checked with reference to the step-out detection information storage table, and whether the relay in question has detected a clockwise Z trajectory or a counterclockwise Z trajectory is checked. Then, processing is performed to display all of the clockwise trajectory indicator lights 91R to 95R and counterclockwise trajectory indicator lights 91L to 95L in the Z trajectory direction indicator light 28 so that they are all turned on.

Furthermore, in step 351, it is determined whether or not a manual inspection command has been input from a timer or the like (not shown). If there is a command, the next step 36 (instruction of the element relay specified by the manual switch SW) is performed. display),
Conversely, if there is no command, proceed to step 352;
Therefore, the operation status of each element relay constituting the step-out detection relay that operated first at that time is processed so as to be provided to the element relay operation indicator 28.

As is clear from the above description, according to the present invention, when a step-out is detected, the operating status of each element relay of the step-out detection relay that has detected the step-out can be automatically displayed.
It is also possible to easily determine whether the out-of-step detection relay operates due to a step-out on a clockwise trajectory or a counter-clockwise trajectory, and even if a step-out is detected on multiple main lines, Since it can be easily determined whether individual step-out relays have operated in sequence, the burden on the operator and malfunctions can be reduced, and at the same time, the cause of the accident can be more easily investigated.
This also makes it possible to provide various useful information regarding the system configuration.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the impedance locus of a Z locus type step-out detection relay, Fig. 2 is a diagram showing an example of a relay board equipped with five sets of conventional step-out detection relays composed of individual relays, and Fig. 3 FIG. 4 is a flowchart showing the operation of the device shown in FIG. 3, FIG. 5 is a diagram showing an embodiment of the present invention, and FIG. 6 is a flowchart showing the operation of the embodiment of FIG. 5. 20...Digital type step-out detection relay, 261
... General operation indicator, 21ND to 25ND ... Operation order indicator, 28 ... Element relay operation indicator,
281-288...Element relay operation indicator light, 29
...Z trajectory direction indicator light, 91R to 95R...Clockwise trajectory indicator light, 91L to 95L...Counterclockwise trajectory indicator light.

Claims (1)

[Claims] 1. In a digital protection relay display device equipped with multiple systems of impedance locus type out-of-step detection relays that detect out-of-step in one power system using a plurality of element relays, one of the above-mentioned out-of-step detection relays is configured. an element relay operation display means for displaying the operating status of each element relay to be operated; and an element relay operation display means for displaying the operation status of each element relay, and each of the element relays constituting the step-out detection relay that operates first when one or more of the step-out detection relays operates. A display device for a digital protection relay, comprising a first detection means for automatically detecting an operating condition and displaying it on the element relay operation display means.