JPH03159515A - Digital control/protective relay analysis maintenance supporting unit - Google Patents

Abstract

PURPOSE:To facilitate development of device and analysis of processing and to reduce labor in maintenance and repair work by analyzing and displaying occurrence of fault in a power system through online real time processing without interrupting power system control or protective function. CONSTITUTION:Processing function relevant to the protective relay in a power digital protective relay unit is divided into eight types of units, where units 1-5 are connected to a general system bus B1 in order to perform data transfer control between the units 1-5. Transfer of data may be triggered by occurrence of system fault or malfunction of the device. The data is displayed in analog waveform on a CRT, and the locus of impedance in a transmission line is plotted on a protective characteristic in order to facilitate analysis. By such arrangement, analysis, display, print out of occurrence of fault in a power system can be facilitated without interrupting the essential control and protective function of power system.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has an easy user interface function,
This invention relates to a support device for digital control and protection systems that facilitates the operation, content analysis, and maintenance of power system control and protection functions.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, it is possible to observe the outline of the response of the output to the input waveform, but it is not possible to: ■ Detailed analysis and display inside the calculation ■ Quantitative analysis and display ■ Analysis and display of impedance locus ■ Man-machine interface No consideration was given to functionality, and there were problems with equipment development, processing analysis, recording, display, and ease of maintenance. Another problem was that a large number of sophisticated measuring instruments had to be prepared. The purpose of the present invention is to develop a device and analyze processing.
The purpose is to make maintenance and repairs easier and labor-saving. Another object of the present invention is to eliminate the need for a large number of sophisticated measuring instruments, display the invisible digital calculation results inside the device as visible analog waveforms and figures, and to understand and analyze the operation. The aim is to make it possible to easily and reliably understand failure analysis, localization, system accident status, etc.

[Means for Solving Problem i] In order to achieve the above object, (1) A data memory for the present invention is provided in the device, and data required for each calculation cycle is stored for a certain period of time.

■ Communication interface circuit (
RS-232C, etc.), and analysis/maintenance support tool (e.g., personal computer) for analyzing the contents of the above memory.
Transfer to.

■ The above-mentioned transfer data can be automatically (online) transferred when the above-mentioned trigger is applied, for example, triggered by the occurrence of a system accident or equipment failure, or upon request from the above-mentioned support device. It will also be possible to start data transfer (offline). ■ On the support device side, when the above trigger occurs. It is possible to automatically display desired data on a CRT monitor, and it is also possible to enable the user to select and display the data he or she needs. ■ The above display data will be displayed in analog waveform on the CRT. ■ Also, the impedance of the power transmission line, etc. can be easily analyzed by plotting its locus on the protection characteristics. (2) In addition, for the above analog waveform, enlargement/reduction display of the amplitude and enlargement/reduction of the time axis can be easily set or selected.

[Function] Not only input waveforms to digital control and protection devices, but also
Intermediate results of various calculations, calculation results of each functionally distributed unit, output waveform, impedance trajectory, etc. can be observed in the form of analog waveforms (continuous figures), and since digital values are input, quantitative data can be obtained. It is possible to analyze and analyze. This allows for equipment development, processing behavior analysis,
Recording becomes easier. Therefore, for example, when a device malfunctions, it becomes easy to analyze, and maintenance and repair become easy.

In addition, it is equipped with an easy-to-use and advanced user interface function, which enables advanced analysis and recording. Therefore, it is possible to realize a highly functional, multifunctional, highly reliable, and advanced device. Furthermore, it is also possible to observe impedance trajectories, which were previously impossible, allowing for more reliable judgment, analysis, display, and guidance. [Example] An example of the present invention will be described below with reference to the drawings. Figure 1 shows an overall block diagram of an embodiment of a power digital protection relay device to which the maintenance analysis support device of the present invention is applied. As shown in the figure, in this embodiment, the processing functions related to the protection relay are divided into eight types of units. These units include a system control unit 1 for the multiprocessor system, an analog input unit 2 that performs A/D conversion of analog input and digital filter processing, a relay calculation unit 3, a sequence processing unit 4, and a setting/display processing unit 5. , a digital input/output unit 6, a display panel unit 7, and a personal computer 8.

Units 1 to 5 are each connected via a general-purpose system bus B1.

Further, the sequence processing unit 4 and the digital input/output unit 6 are connected by an input/output I/O bus B2 different from the general-purpose system bus B1.

Note that the system includes a power supply (not shown), which drives each unit. Next, an example of data transfer control between units 1 to 5 connected to the general-purpose system bus B1, that is, an example of data transfer control of a multiprocessor, will be explained using FIGS. 2 and 3. In FIG. 2, units 1-5 are exactly the same as units 1-5 in FIG.

In the system control unit 1, 10 is a control section including a general-purpose microprocessor, 11 is a direct memory access controller (DMAC) for high-speed data transfer, and 12 is a data memory.

In the analog input unit 2, 20 is a signal processing section including a digital signal processor DSP of floating point arithmetic type (fixed point arithmetic type is also possible), and 21 is a signal processing section including, for example, a dual port random access data memory (DPR).
It is a dual-port data memory consisting of AM). In the relay arithmetic unit 3, 30 is an arithmetic processing unit including a DSP of floating point arithmetic type (fixed point arithmetic type is also possible), and 31 is a dual port data memory consisting of a dual port random access data memory (DPRAM). ? In the sequence processing unit 4, 40
4 is a sequence processing unit including a general-purpose microprocessor;
Similarly to the data memory 31, 1 is a dual port data memory consisting of a D P RAM.

In the setting/display processing unit 5, 50 is a setting/display processing section including a general-purpose microprocessor, and 51 is a DPRA.
It is a dual port data memory consisting of M. In addition, the signal line α in Fig. 2 is an interrupt signal for notifying the data acquisition cycle, and the signal lines a to e are for abnormality notification and abnormality recognition signals (SYS FAIL) of each unit.
). Next, the data transfer method in this embodiment will be explained with reference to FIG.

Figure 3 represents the timing of data transfer in chronological order. In Fig. 3, (a) is system ■processing of control unit 1, (
b) shows the processing of the analog input unit 2, (c) shows the processing of the relay calculation unit 3, (d) shows the processing of the sequence processing unit 4, and (e) shows the processing of the setting/display processing unit 5. show. In the figure, the directions of dotted arrows from ■ to ■ indicate the direction of data transfer. first,
The system control unit 1, which is a master unit (a unit that can obtain the right to use the general-purpose system bus and start data transfer), receives N cycles from the analog input unit 2, which is a slave unit (a unit that responds to data transfer performed by a mask). Enter the data.

This data is, for example, voltage and current information of an electric power system, which is obtained by digital filtering in N periods by the analog input unit 2 using sample data before N-1 periods. This data ■ may be input by the control section 10 in the unit 1. DMAC1
1 may be used. The input data ■ is then stored in the data memory l2. Next, the system control unit 1 transfers the input and stored data 1 to the relay calculation unit 3, which is a 5-slave unit.

This is indicated by ■ in Figure 2.

Furthermore, the relay calculation result (using the analog input unit output from the N-1 period or earlier) calculated in N cycles is inputted and stored in the data memory 12 in the unit 1.

Next, the system control unit 1 transfers the input and stored data (2) to the sequence processing unit 4, which is a slave unit. This is ■ in Figure 2. Furthermore, the sequence processing result (N-1
(using the relay calculation results before the cycle) is input and stored in the data memory l2 in unit 1. Next, the system control unit 1 transfers the input and stored data to the slave unit
Data is transferred to display processing unit 5. This is ■ in Figure 2. Furthermore, the relay setting value ■ stored in the DPRAM in the unit 5 is inputted and stored in the data memory 12 in the system control unit 1. This data (■) is a setting value for the relay, so it is included in the above-mentioned data (■), and the system control unit 1 transfers it to the relay calculation unit 3 together with the data input from the unit 2 at every sampling. DPRAM in unit 3
3l. By doing this, even if there is a change in the setting value, it can be dealt with immediately. As is clear from FIG. 3, it can be seen that each unit can fully process the functions assigned to it until the next sample time after each data transfer is completed. In other words, each unit can perform arithmetic processing using the data at that time by using the entire sample period after data transfer at that time is completed. This is due to the effect of providing the dual port data memories 21, 31, 41.51 in each unit shown in FIG. The data transfer timing shown in FIG. 3 is performed by the interrupt signal line α shown in FIG. This signal line α is a signal line synchronized with a sample command for sampling the voltage and current of the power system, and is emitted from the unit 2. This timing is obtained by dividing the sampling period of the original sampling signal. Data transfer mentioned above■
It goes without saying that ~■ is performed subsequent to the data transfer in ■. The above describes the functional division of the digital protection relay device to which this embodiment is applied, the overall block configuration, and an example of data transfer between the divided units. By the way, in the above embodiment, the system control unit 1 controls the other four units 2 to 5.
However, the units that can be controlled by the system control unit 1 are not limited to this. As shown in FIG. 3, the number of controlled units can be further increased as long as the transfer processing for all units can be completed within one cycle of system control processing. To add a unit, connect the unit to the system path B1, set an address for the unit, and change the control program of the system control unit. For example, if the purpose of adding a unit is to improve the processing capacity of a certain unit, it is sufficient to add a unit with the same function. Additionally, if you want to add a different function to the system, you can simply add a unit with that function. For example, by adding more analog input units, more signals can be processed. Additionally, by adding more relay calculation units, more calculations can be executed, making the relay more multifunctional and sophisticated. On the other hand, various functions can be added to the digital relay by adding units with different functions. For example, by providing a communication function, it is possible to exchange information with other relay devices, or to use this system as a child device to centrally control the main device.

In addition, it goes without saying that in this system, it is possible not only to increase the number of units, but also to reduce and change them. For example, the computational unit can be replaced with a unit that can perform faster processing. As a result, for example, the computational processing capacity within one cycle is improved, so the amount of information that can be processed increases. Therefore, it is possible to process more signals. Additionally, operations that were previously executed using multiple processing units can now be processed using fewer units, reducing the number of units. Conversely, if the information to be processed is the same, higher precision and more complex operations can be executed within a limited amount of time, making it possible to improve the accuracy and functionality of the system. This kind of thing is
It can also be applied when constructing systems, and by selecting units according to the purpose, various systems can be constructed in addition to digital relay devices. In this way, according to the method of this embodiment, various systems can be constructed depending on the purpose, and the system once constructed can be expanded. It is possible to construct a flexible system that can easily add functions, increase speed, increase accuracy, and improve functionality. Next, we will provide an overview of power digital protection devices. An overview of the processing will be explained using Figures 4 and 5. First, an overview of the processing of the power protection device will be described using Figure 4. In step 2001, information from the power system, eg, voltage and current of power transmission lines, is input, and analog quantities are further converted into digital quantities. In step 2002, an electrical quantity for accident detection or control is derived. Derivation of this quantity of electricity includes the voltage at the time of the power system fault, the magnitude of the current, the impedance Z to the fault point, the resistance component R, the reactance component X, the direction of the fault point, the frequency at the time of the fault, etc.
In step 2003, the amount of electricity derived in step 2002 is compared with a predetermined set value. If it is determined as an accident as a result of the comparison, the process advances to step 2004.

In step 2004, it is determined whether the accident condition determined in step 2003 continues, and if so, the process advances to step 2005. In step 2005, since it is determined that an accident has occurred, that information is stored. In step 2006, based on the operations of the various relays stored in step 2005, sequence processing is performed in a known system (sometimes in combination with external conditions and timers).
If an accident is determined to have occurred, a command is issued to the circuit breaker to shut it off. Step 2007 is a device inspection/monitoring process.

A digital control protection device for electric power executes the above-mentioned processing within the sampling period of the analog input, and repeatedly executes it for each sample. Figure 5 shows an example of the characteristics of a known reactance relay (1 element) and a Mori relay (1 element). In the figure, jx is the inductive reactance component of the impedance. In step 2002 of FIG. 4, the relay element is
0 to 50 elements are processed, and the sequence processing in step 2006 is to perform the desired sequence processing corresponding to the system based on the outputs of these relay elements. Z1 and Z2 shown in FIG. 5 are set values, and in the case of a protection relay, these values determine the protection range. It is a well-known technology that this value can be changed online from outside the device by a human in the event of a change in the power system or a corresponding change in the protection range. Having provided an overview of the data transfer and processing of the digital relay above, we will now provide an overview of the maintenance analysis device of unit 8 in FIG. 1.

The maintenance and analysis equipment in Unit 8 is equipped with a microprocessor, memory, CRT controller, keyboard, controller, printer controller, floppy disk unit, etc., and is connected to external devices such as a monitor, keyboard printer, and floppy disk. In other words, it is a personal computer. First, we will provide an overview of the process.

Figure 6 shows an example of the CRT screen of the support device. That is, the data stored in the unit 1 in FIG. 1 is input and the digital values are displayed in an analog waveform. In Figure 6, 1 is the input voltage from the power system, 2 is the input current, 3 is the digital filter output of the above voltage, 4 is the digital filter output of the above current, 5 is the intermediate result of calculation, and 6 is the output of the reactance relay. This is an example. Further, 7 shows an example in which the locus of impedance is plotted on the protection characteristic.

In this way, the maintenance analysis support system ￥L (Figure 1 Unit 8)
The analysis is performed by displaying the digital data stored in the system control unit l shown in Fig. 1 as a continuous analog waveform on a CRT so that it can be easily understood by the human eye. This allows for easy analysis, recording, maintenance, and repair. Furthermore, in order to ensure and advance the above functions, CR
On T, as shown in Fig. 7, select only one waveform on Fig. 6 (current filter output waveform a in Fig. 6 4),
It is also possible to expand the amplitude and time axis. Figure 8 shows an example in which the waveforms 1 to 6 in Figure 6 are displayed on a CRT with the time axis enlarged twice. Further, FIG. 9 shows an example by enlarging and displaying only the locus of impedance 7 in FIG. 6. From the above explanation, you can understand that the maintenance analysis support device can freely select the waveforms and functions of the department that require it, and display and provide guidance in the required size. Next, we will explain the system control unit that stores the data described above. Figure 10 shows the first
The block configuration of the system control unit 1 shown in the figure is shown. In the figure, 100 is a general-purpose microprocessor;
01 is a direct memory access controller (hereinafter abbreviated as DMAC) for high-speed data transfer. Further, 102 is a program memory using, for example, PROM, 103 is a data memory using RAM, and 104 is an electrically erasable/rewritable nonvolatile memory E"FROM.
A setting data memory 105 stores setting data such as setting values, constants, coefficients, etc. using a static random access memory (SRAM) and a non-volatile memory E"FROM similar to the above on the same chip. (I.C.
) to store data at high speed when a failure occurs,
This is an analysis data memory for performing failure analysis. Furthermore, 106 is a system logic having a system reset, a system clock, a bus access arbitration circuit, etc.;
07 is a system interrupt determination circuit, 108 is an abnormality detection circuit, and 109 is a communication interface X (RS-232C) ryl path for connecting to a personal computer, etc.
lO is the system bus interface circuit. The analysis data memory 105 is an SRAM as described above.
and E"FROM, and all data in the SRAM is stored in E"FROM by a store control signal (pulse).
All data from E"FROM is transferred to SRAM at once by the recall control signal (pulse).
It has a function to transfer to. Therefore, for example, by creating a structure in which the store control signal is generated when the power is turned off or when an abnormality is detected in the unit, the immediately preceding data can be stored in the non-volatile E"FROM, making it possible to restart operation or analyze failures. Preferably, the microprocessor 100 is connected to a local bus LB.
C 1 0 1 . Setting data memory 104, analysis data memory 105, system bus interface circuit 1
10, program memory 102, data memory 103,
Abnormality detection circuit 108, communication interface circuit 109
and a system interrupt determination circuit 107 are connected. The waveforms (data) shown in FIGS. 6 to 9 are obtained by transferring the data stored in the data memory 103 and the analysis data memory 105 through the interface circuit 109 in FIG. The data is transferred to a personal computer, that is, a support device. The support device displays this data on a CRT. Next, examples of data storage for storing data necessary for analysis and maintenance as shown in Figures 6 to 9 will be shown. Figure 11 shows an example of a data memory map. In the figure, ■ The horizontal direction (1, 2.3...n) is the number of data samples for each item. For example, if n=240, 1
If the sampling period is 1.67 mS (1/600 Hz), in a 50 Hz system, there are 12 samples/1 cycle, so 20 cycles are stored. ■ The vertical direction (1.2.3...n) indicates each item to be analyzed and displayed as shown in Figures 6 to 9. Examples include input voltage and current, outputs of each digital filter, intermediate results of control and protection calculations, outputs of each relay, intermediate results of sequences, calculated impedance of power transmission lines, etc. ■ The vertical direction (I.■...M) indicates, for example, the number of power transmission line accidents or the number of device failures to be stored. For example, if M=10, it means that up to 10 of the latest power transmission line accidents are stored for each item (1, 2...m). If we consider the number of occurrences of equipment failures, this indicates that 10 occurrences of equipment failures are stored for each item.

An example of data memory processing to realize the memory map described above will be explained using FIG. 12. Figure 12 shows the 10th
An example of the processing flow is shown when each data is stored in the data memory 103 in the system control unit shown in the figure. The process will be explained below according to the flow diagram. First, initial processing is performed in step 200, and step 2
01 performs the intended processing of the system control unit. At step 202, data for each item is stored. In step 203, it is determined whether the counter C is a certain constant value. This counter C is a counter that counts the number of samples of stored data in the horizontal direction in FIG. On the other hand, if the counter C has not reached a certain predetermined value (for example, 240), the process advances to step 204 and the counter is incremented. If the counter C reaches a predetermined value in step 203, the process proceeds to step 205, where it is determined whether or not there is a trigger. This trigger may be, for example, whether an accident has occurred on a power transmission line, whether some kind of protection relay is operating, or whether a defect has occurred in a device. If no trigger has occurred in step 205, the process proceeds to step 206, where the counter C is initialized, and the process proceeds to step 209. If a trigger has occurred in step 205, the process proceeds to step 207, where a counter M different from the counter n is incremented. Then, the process proceeds to step 208, where the counter C is initialized.
The counter M mentioned above is the number of system accidents shown in Fig. 11,
Alternatively, it is a counter that counts the number of times a device failure occurs. In step 209, it is determined whether this counter M has reached a predetermined value, and if it has not reached the predetermined value, the process proceeds to step 210, in which it is determined whether or not there is a trigger. If there is a trigger, proceed to step 212;
Set the above counter C to half of the desired value (for example, 240) (
For example, set it to 120) and prepare for the next sample data. Here, if a trigger occurs, step 212
The reason why the counter C was set to 120 is because 120 sample data were stored before the trigger occurred, and 120 sample data were stored after the trigger occurred. In step 209, the counter M is set to a predetermined value (for example, M=10
), the process proceeds to step 211, where the counter M is initialized, and the process proceeds to step 210, where the same process is executed. From the above explanation, as shown in FIG. 11, each sample. It will be understood that data according to each item is always stored for a predetermined period. Next, using Figure 13,
An example in which the system control unit shown in FIG. 10 transfers data to the analysis and maintenance support system (personal computer) via the communication interface circuit 109 shown in FIG. 5 will be described. Regarding data transfer, we will discuss real-time online processing in which the system control unit transfers data while executing the desired processing, and offline processing in which the system control unit cancels the intended processing and only transfers data. First, in step 300, it is determined whether or not an interrupt for the sampling period from the analog input unit 2 in FIG. Execute. After that, the process advances to step 302 and memory processing of the data is performed. This memory processing
It performs the processing shown in Figure 2. Then step 303
Proceed to install the support equipment for this system control unit.
! (PC) to determine whether to transfer data online in real time. If the result of this determination is that it is offline. The process proceeds to step 304, and since this is an offline process, it is determined whether there is a data transfer request from the support device (personal computer). If there is a data transfer request, the process proceeds to step 305, and the data to be transferred is transferred to the 10th @. Communication interface circuit (ACIA)
) and proceed to step 306. Step 306
Then, it is determined whether the data transfer has been completed, and it is determined whether the data (1 byte) has been transmitted to the support device. If the data (1 byte) has been transmitted, the process advances to step 307. Determine whether all data to be transferred has been completed. If the transfer of all data has not been completed, the process proceeds to step 308, and after setting the next data, the process proceeds to step 306, and the same process is repeated. If it is determined in step 303 that online data transfer is required, the process proceeds to step 309, where it is determined whether or not there has been a change in the counter M shown in FIGS. 11 and 12.
That is, whether or not the above-mentioned M has changed means determining whether or not the above-mentioned trigger has occurred, that is,
It is determined whether an accident has occurred in the power transmission line, and if M has changed, it means that a system accident has occurred or a defect has occurred in the equipment, so the transferred data is automatically transferred to step 305 in step 310. Similarly, set it in the communication interface circuit. In step 311, the set data (1
(byte) has finished being transferred to the support device (computer). When the data transfer of 1 byte is completed, the process proceeds to step 312, and it is determined whether the transfer of all the data to be transferred has been completed. If the transfer of all the data has not been completed, the process proceeds to step 313. , sets the next data to be transferred in the communication interface circuit, returns to step 300, and prepares for the next sample data. The same process is executed repeatedly below. From the above explanation, the details of how the system control unit 1 shown in FIG. 1 transfers data to the support device If (personal computer) online or offline can be understood. Finally, support equipment using Figure 14! We will explain the data reception, analysis, and display overview on the (personal computer) side. 14th
In the figure, in step 400 it is determined whether the
The process proceeds to step 402, where it is determined whether all the required data has been received. If all the data has been received, the process proceeds to step 402, where the man-machine process determines what data to display and how to display it. Interface processing, ie, instructions and selections for outputting and displaying waveforms as shown in FIGS. 6 to 9, are performed. When all instructions and selections are completed, the process proceeds to step 404, where waveforms and figures are plotted on the screen (CRT) of the support device. If it is determined that it is online in step 400, step 4
The process proceeds to step 405, where it is determined whether or not all the necessary data has been received. If all the data has been received, the process proceeds to step 406, where the desired plotting process (on the CRT of the support device) during online processing is performed. ). after that,
It is determined whether there is a plot change for detailed analysis or display, and if there is a plot change (if a plot change is desired), the process proceeds to step 407, where it is determined whether there is a trigger, that is, if the plot is changed continuously. It is determined whether an accident has occurred in the power transmission line, etc., and if a trigger has occurred, the process returns to step 406. Also,
If no trigger has occurred, the same man-machine interface processing as in step 402 is executed to output, display, and analyze the required data.
Below, exactly the same process is executed repeatedly.
From the above explanation, you will be able to understand the details of data processing and display on the support device (personal computer) side. In addition, in the explanation so far, as shown in Figure 1, we have described an example in which the analysis and maintenance support device is connected to the system control unit, but it is also possible to connect it to other units and perform processing in exactly the same way as the system control unit. can be easily inferred. In the above explanation, the system control unit 1 and support equipment shown in FIG. ! The data transfer between 8 and 8 was explained using a wired image (for example, RS-232C, etc.), but it is easy to imagine that it could also be done wirelessly. Furthermore, it is easy to assume that infrared light may be used. [Effects of the Invention] According to the present invention, (1) Analysis, analysis, display, printout, etc. of the occurrence status of power system accidents can be easily performed without stopping the original power system control and protection functions. (2) Since it stores a large amount of digital data, equipment failure analysis can be performed quantitatively, resulting in significant labor savings in maintenance and repairs and speeding up localization. (3) Since the digital control/protection device and support device are integrated, it is possible to develop the device and analyze, analyze, and evaluate the processing (algorithm). Verification and recording can be done accurately and quickly. (4) Plots of impedance trajectories, which were previously impossible, can be displayed in correspondence with relay operation outputs and inputs, allowing for more advanced approaches. (5) Data in the middle of calculations can be easily displayed and output in the form of analog waveforms, allowing sophisticated and quantitative analysis. (6) Device failure analysis, etc., was previously performed using a large number of highly accurate measuring instruments, but these measuring instruments are no longer necessary. (7) Since data for a certain interval is stored, advanced analysis (e.g. frequency analysis, feature extraction, etc.) using this data is possible. (8) Since a personal computer is used as the support device, based on the transferred data, automatic measurement of operating time, guidance on types of power transmission line accidents, automatic analysis and localization of equipment failure locations, and prediction of equipment failure It can perform processing such as guidance.

[Brief explanation of the drawing]

Figure 1 shows the overall configuration of an embodiment of the present invention. Block diagram, Figure 2 is a block diagram showing an example of inter-unit data transfer control, Figure 3 is a time chart showing an example of the timing of an example of inter-unit data transfer, and Figure 4 is protection relay processing. A flowchart showing an overview, FIG. 5 is a diagram showing known examples of protection relay characteristics (Mau relay and reactance relay), FIG. 6 is a diagram showing an example of display on the CRT screen of the analysis and maintenance support device, and FIG. 6 shows an example of an enlarged display of one waveform, FIG. 8 shows an example of an enlarged display of the time axis of the display in FIG. 6, and FIG. 9 shows an example of an enlarged display of only one figure in FIG. 6. 10 is a block configuration diagram of the system control unit that transfers data with the support device, FIG. 11 is a diagram showing an example of a memory map for data recording, and FIG. 12 is a data memory processing flow within the system control unit. Figure 13 is a data transfer processing flow diagram of the system control unit to the support device.
Figure 14 is a flow diagram of the data reception and display processing of the analysis and maintenance support device. 1... System control unit, 2... Analog input unit, 3... Relay calculation unit, 4...
...Sequence processing unit, 5...Setting/display processing unit, 6...Digital input/output unit, 7...Table 4, Figure 5 (2l) Figure 6, Figure 7, Figure 8, Figure 8

Claims (1)

[Claims] 1. A signal representing the state of the power system is taken in, digital calculation processing is performed on the signal based on a predetermined algorithm, and the power system is controlled or protected based on the calculation result. In power control and protection systems, digital control is characterized by making it possible to analyze and display the occurrence of power system accidents and calculation processing through online real-time processing without stopping power system control or protection functions.・Protection relay analysis and maintenance support device. 2. In a power control/protection system that takes in a signal representing the state of a power system, performs digital calculation processing on the signal based on a predetermined algorithm, and controls or protects the power system based on the calculation result. , multiple items such as input signals, intermediate calculation results, and outputs are always stored for a certain period of time, and the stored data is frozen in response to a system failure or equipment failure signal, and the frozen data can be selected and displayed at will. A digital control/protection relay analysis/maintenance support device featuring: 3. A digital control/protection relay analysis/maintenance support device according to claim 2, characterized in that frozen digital data stored over a certain period of time is displayed or plotted as an analog waveform. 4. A digital control device according to claim 2, characterized in that a plurality of blocks are provided with a plurality of frozen data groups, and these can be arbitrarily selected and displayed, plotted, or analyzed as desired. Protection relay analysis and maintenance support device. 5. In a power control/protection system that takes in a signal representing the state of a power system, performs digital calculation processing on the signal based on a predetermined algorithm, and controls or protects the power system based on the calculation result. A digital control/protection relay analysis/maintenance support device characterized by displaying or plotting the locus of impedance of a power transmission line on protection or control characteristics. 6. In a power control/protection system that takes in a signal representing the state of a power system, performs digital calculation processing on the signal based on a predetermined algorithm, and controls or protects the power system based on the calculation result. , a function that automatically analyzes or analyzes the stored data according to the above claim 2, and automatically reports or provides guidance on the nature of the accident in the power system, the operating time of the protective relay, the location of the occurrence of equipment failure, etc. A digital control/protection relay analysis/maintenance support device characterized by: