JP2011061962A - Protective relay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective relay that predicts the occurrence of failures in future. <P>SOLUTION: The protective relay 1 inputs a current of a power feed line L2 from a current sensor 4, inputs a voltage of a power transmission system L1 from a voltage sensor 5, and transmits a block command signal to a blocker 3 when detecting an overcurrent or an overvoltage. In the protective relay 1, a processing unit 11 inputs a digital signal of a DC voltage which is converted from an AC voltage of the power transmission system L1 from an analog/digital converter A/D, inputs an output voltage of an AC from a power supply unit 15, and inputs inspection data (test current, test voltage and operation time) from a test device 2 which is connected at inspection via an external interface 14. Next, each of the input data is stored in a memory 12, and a time change of the input data is displayed on a display 13. Then, the time change of the input data is compared with the past data stored in the memory 12 and a setting value, and when it is predicted that there is a probability that the failure may occur in the protective relay 1, an alarm of the occurrence of the failure is displayed on the display 13. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a protective relay having a function of storing an inspection record and a function of predicting a failure.

  Conventionally, inspection records of protective relays are managed on paper, and many of these records are stored in cabinets of power company offices. Then, when inspecting the protective relay, in order to compare and examine the change trend of the inspection item at that time with the past inspection result, the past record is taken out from the storage location and taken to the inspection location. Such inspection work is carried out about once every 3 to 6 years.

  Patent Document 1 discloses a technique for comparing a real operation state with a past operation state stored in advance for a control circuit including a relay, and detecting a failure of the relay on the condition that the operation pattern is different. It is disclosed.

JP-A-8-54432

By the way, in the above-mentioned conventional inspection work, since the inspection record is a paper surface, there are the following problems.
(1) Past trends including the inspection results at that time cannot be immediately confirmed in a highly visible style such as a graph.
(2) To confirm the trend, it is necessary to input the inspection result to a PC (Personal Computer) or the like, start the spreadsheet software, and display the graph, which is troublesome.
(3) It takes a lot of time and effort to file paper in the office, and it may take time to find out when past inspection records are urgently needed such as in emergency response.
(4) Carrying is time-consuming and may be lost while moving from the office to the inspection site.
(5) The time interval for carrying out the inspection work is long, and the characteristic tendency of the inspection items cannot be grasped in detail.

According to the above, since the inspection record is paper, the past trend cannot be confirmed immediately, and since the detailed trend cannot be grasped because the interval of the inspection time is long, it is difficult to predict a future failure.
Patent Document 1 discloses a technique for detecting a failure from an on / off state of a contact, and does not have a function of predicting a future failure from measured values such as current and voltage.

  This invention is made | formed in view of the said subject, The main objective is to provide the protection relay which can generate | occur | produce future failure.

In order to solve the above-mentioned problems, the present invention is a protective relay, which stores data acquired periodically for checking the operation of the protective relay as time-series data, and the time-series data is acquired. Means for storing data indicating that a failure has occurred in association with the time-series data when a failure occurs in the protective relay after the acquisition, and the latest data acquisition of the stored time-series data There is a correlation of a predetermined degree or more between the first data group including time series data after the time point before the predetermined period and the second data group including time series data other than the first data group. Data indicating that there is the correlation between the means for determining whether or not the first data group and the second data group and that the failure has occurred is included in the second data group Be If it is stored in association with the time series data, characterized by comprising a means for predicting the in the protective relay fault might occur, the.
According to this configuration, a failure that occurs in the protective relay can be predicted in advance.

Further, the present invention may further include means for outputting that the protection relay is predicted that a failure may occur in the protection relay.
According to this configuration, it is output that there is a possibility of failure in the protective relay, so the administrator of the protective relay can take measures such as repairing the protective relay until the actual failure occurs. Can be taken.

Further, in the protection relay, the present invention is based on the time of the first data group, the time of the second data group, and the time when the failure occurs in the protection relay after the second data group. It is good also as a means to predict the time when a failure will generate | occur | produce in the said protection relay from now on, and a means to output the time when a failure will occur in the predicted said protection relay.
According to this configuration, since the failure occurrence time of the protective relay is predicted and output, the administrator of the protective relay can plan a work schedule such as repair.

Further, in the protection relay, the present invention provides that the correlation between the first data group and the second data group and data indicating that the failure has occurred are the second data group. In the case where the protection relay is not stored in association with the time-series data included in the data, the protection relay may be further provided with a means for determining that it is normal.
According to this configuration, the recent data group not only has no correlation with the data group at the time of failure occurrence, but also has a correlation with the data group at the time of failure occurrence, so that the protection Confirmation that the relay is normal can be obtained.

  In the protection relay, the data may be an output voltage of a power supply, a voltage obtained by converting an alternating voltage of a power transmission system into a direct current, a test current, a test voltage, or an operation time.

  In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the description of the mode for carrying out the invention and the drawings.

  According to the present invention, it is possible to provide a protective relay capable of predicting the occurrence of a future failure.

It is a figure which shows the structure of the protection relay 1 and its periphery. It is a figure which shows the structure of the data memorize | stored in the memory | storage part 12 of the protection relay 1, (a) shows the structure of the data of the memory | storage part 12, (b) shows the structure of inspection data 12D, (c) is The configuration of the measurement data 12E is shown, and (d) shows the configuration of the past data 12F. 3 is a flowchart showing processing of the protective relay 1; It is a figure which shows the screen which displayed the time change of the output voltage value with the graph, (a) is the trend of the output voltage value of the power supply unit 15 recently, (b) is a failure in the past. The trend of the output voltage value of the power supply unit 15 is displayed, (c) is the trend of the output voltage value of the recent analog-digital converter A / D, and (d) is the past. The trend of the output voltage value of the analog-digital converter A / D when a failure occurs is displayed.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The protective relay according to the embodiment of the present invention stores data of inspection results including automatic and manual, stores temporal changes of data including past fault occurrences, and recent data includes When a temporal change having a high correlation with data at the time of the occurrence of a failure in the past is shown, it is predicted that “there is a possibility of failure occurrence” and output.

≪Configuration and overview of protective relay and its surroundings≫
FIG. 1 is a diagram illustrating a configuration of the protective relay 1 and its surroundings. The power transmission system L1 is a bus that is supplied with power from a substation. The power supply line L2 is connected to the power transmission system L1, receives power supply from the power transmission system L1, and supplies power to the power equipment 6 installed thereunder. The circuit breaker 3 is installed on the power supply line L2, receives the interruption command signal from the protective relay 1, and interrupts the power supply line L2. The current sensor 4 is installed on the feeder line L2, measures the current flowing through the feeder line L2, and transmits it to the protective relay 1. The voltage sensor 5 is installed on the power transmission system L1, measures the voltage of the power transmission system L1, and transmits the voltage to the protective relay 1. The power device 6 is a load that consumes power, and receives power supply from the power supply line L2. The protective relay 1 is connected to the circuit breaker 3, the power sensor 4, and the voltage sensor 5. The current of the power supply line L2 is input from the current sensor 4, the voltage of the power transmission system L1 is input from the voltage sensor 5, and the overcurrent or overvoltage is input. Is detected, a break command signal is transmitted to the breaker 3. The test device 2 is connected to the protective relay 1 when testing (checking) the characteristics and operation of the protective relay 1.

  The protective relay 1 detects an abnormality in the power transmission system L1 and the power supply line L2 from a telemeter such as voltage, current, frequency, etc., and outputs a cut-off command signal to the circuit breaker 1 to place the accident point in a power failure state. Thereby, it is possible to prevent the power device 6 connected to the power supply line L2 from failing. As shown in FIG. 1, the protective relay 1 includes analog filters AF1 and AF2, AC / DC converters IT1 and IT2, sample hold circuit S / H, analog / digital converter A / D, processing unit 11, storage unit 12, and display unit. 13, an external interface unit 14 and a power supply unit 15.

  The analog filter AF1 inputs an alternating current of the power supply line L2 from the current sensor 4, extracts a predetermined direct current component from the alternating current, and outputs it. The analog filter AF2 inputs the AC voltage of the power transmission system L1 from the voltage sensor 5, extracts a predetermined DC component from the AC voltage, and outputs it. The AC / DC converter IT1 receives an alternating current from the analog filter AF1, converts it to a direct current, and outputs it. The AC / DC converter IT2 receives an AC voltage from the analog filter AF2, converts it to a DC voltage, and outputs it. The sample hold circuit S / H is a circuit that receives and samples (samples) analog signals of DC current and DC voltage from the AC / DC converters IT1 and IT2 and holds (holds) them for a predetermined time. That is, the instantaneous value of the changing analog signal is maintained so that the analog-to-digital converter A / D can execute an accurate conversion process. The analog-digital converter A / D receives an analog signal from the sample hold circuit S / H, converts it into a digital signal, and outputs it to the processing unit 11.

  The processing unit 11 exchanges data between the units and controls the entire protective relay 1. The processing unit 11 is realized by a CPU (Central Processing Unit) executing a program stored in the storage unit 12. The As processing by the processing unit 11, a DC voltage digital signal is input from the analog / digital converter A / D, a DC output voltage is input from the power supply unit 15, and inspection data is received from the test apparatus 2 via the external interface unit 14. Each input data is stored in the storage unit 12, and the temporal change of each input data is displayed on the display unit 13. Then, when it is determined that there is a possibility that the protective relay 1 becomes a failure as compared with past data or set values stored in the storage unit 12, an alarm is displayed on the display unit 13.

  The storage unit 12 stores data from the processing unit 11 and reads the stored data, and is realized by, for example, a nonvolatile storage device such as a flash memory or a hard disk device. The display unit 13 is a part that displays data according to an instruction from the processing unit 11, and is realized by, for example, a liquid crystal display (LCD). The external interface unit 14 is between the test device 2 and the circuit breaker 3 and the processing unit 11 and relays data transmission / reception between the test device 2 and the processing unit 11 and between the circuit breaker 3 and the processing unit 11. The power supply unit 15 is a DC main power supply of the protective relay 1 and outputs the voltage value of the power supply to the processing unit 11 as needed in order to receive monitoring of the power supply state.

  When the protection relay 1 is inspected, the test apparatus 2 is connected to the analog filters AF1 and AF2 and the external terminal of the external interface unit 14. Next, the processing unit 21 provided in the test apparatus 2 supplies a test current to the external terminal of the analog filter AF1 of the protective relay 1 and applies a test voltage to the external terminal of the analog filter AF2. The current and voltage are continuously applied for a predetermined time, and the time when the output is stopped is stored. And the interruption | blocking command signal is received from the external interface part 14 of the protection relay 1, and the received time is memorize | stored. The operation time of the protective relay 1 is calculated and stored by subtracting the output stop time from the signal reception time. Thereafter, the test current, test voltage, duration and operation time are transmitted to the external interface unit 14 as inspection data.

<< Data structure >>
FIG. 2 is a diagram illustrating a configuration of data stored in the storage unit 12 of the protective relay 1. FIG. 2A shows the data structure of the storage unit 12. The storage unit 12 stores a program 12A, basic data 12B, settling value data 12C, inspection data 12D, measurement data 12E, and past data 12F. The program 12A is a program that realizes the function of the protective relay 1 by being loaded into the processing unit 11 and executed. The basic data 12B is the minimum data necessary for executing the program 12A, and is control data that is referred to and updated by an IPL (Initial Program Loader), an OS (Operating System), or the like. The set value data 12C is a reference value for the set operation of the protective relay 1, and is, for example, a power output value, an operating current value, an operating voltage value, an operating time, or the like. The inspection data 12 </ b> D is data relating to the inspection performed by the test apparatus 2 and is transferred from the test apparatus 2 to the protective relay 1. The measurement data 12E is voltage data acquired from the power supply unit 15 and the analog / digital converter A / D. The past data 12F is data in which the history of the inspection data 12D and the measurement data 12E is recorded in time series.

  FIG. 2B shows the configuration of the inspection data 12D. The inspection data 12D includes a test current 12D1, a test voltage 12D2, a duration 12D3, and an operation time 12D4. The test current 12D1 is a value of a current input from the test apparatus 2 to the protective relay 1 at the time of inspection. The test voltage 12D2 is the value of the voltage supplied from the test apparatus 2 to the protective relay 1 at the time of inspection. The duration 12D3 is a time during which the current and voltage are continuously applied. The operation time 12D4 is a time from when the protective relay 1 receives a current and a voltage from the test device 2 to when the cutoff command signal is output.

  FIG. 2C shows the configuration of the measurement data 12E. The measurement data 12E includes a power supply output voltage 12E1, an AC / DC conversion voltage 12E2, and an AC / DC conversion current 13E3. The power supply output voltage 12E1 is a value of the power supply voltage that the power supply unit 15 outputs at any time. The AC / DC conversion voltage 12E2 is a value obtained by converting the AC voltage of the power transmission system L1 output from the analog-digital converter A / D at any time into a DC voltage. The AC / DC conversion current 12E3 is a value obtained by converting the alternating current of the feeder line L2 that is output from the analog-digital converter A / D as needed into a direct current. Note that the power supply output voltage 12E1, the AC / DC conversion voltage 12E2 and the AC / DC conversion current 12E3 hold, for example, data from the start of the operation of the protective relay 1 or the restart of operation due to failure recovery.

  FIG. 2D shows the configuration of the past data 12F. The past data 12F is divided into normal data 12F1 and failure data 12F2. The normal data 12F1 is data in which no failure has occurred after the time-series data of the inspection data 12D and the measurement data 12E. The failure data 12F2 is data in which the failure has occurred after the time series data of the inspection data 12D and the measurement data 12E (“data indicating that the failure has occurred is included in the second data group in the claims”). (Corresponding to time-series data in the case of being stored in association with time-series data). Therefore, the time-series data is accumulated as normal data 12F1 while the normal state continues, but when a failure occurs, the data up to that point is changed from the normal data 12F1 and re-stored as failure data 12F2. The normal data 12F1 and the failure data 12F2 are recorded, for example, data acquired from the start of operation of the protective relay 1 or the start of re-operation due to failure recovery. Further, the range that is re-stored from the normal data 12F1 as the fault data 12F2 is not all the data acquired from the start of the operation of the protective relay 1 or the restart of the fault recovery, but from the time of the fault to the specified time before Good. The specified time depends on the type of failure, but the timing of periodic inspections and the like may be used as a break. In this case, data before the specified time is continuously stored as normal data 12F1.

≪Protective relay processing≫
FIG. 3 is a flowchart showing the processing of the protective relay 1. This process is performed as an automatic inspection once a day for 1 to 10 days, for example. Measurement data and inspection data are acquired and stored, and recent time changes including the present are displayed, as well as past data and settling value data. When it is predicted that there is a possibility of failure, the fact is displayed. Note that the result of the inspection of the protective relay 1 by the test device 2 is transmitted from the test device 2 to the external interface unit 14 of the protective relay 1 every time inspection is performed, and the processing unit 11 sends the storage unit 12 from the external interface unit 14. Is stored in the inspection data 12D. In addition, the processing unit 11 of the protective relay 1 sends a disconnection command signal to the circuit breaker 3 via the external interface unit 14 when an overvoltage of the power transmission system L1 or an overcurrent of the feeder line L2 is detected separately from this processing. Process to send.

  First, when the power supply (power supply unit 15) of the protective relay 1 is turned on, the program 12A stored in the storage unit 12 is loaded into the processing unit 11 and the processing is executed. In the protective relay 1, when a trigger indicating that automatic inspection should be performed is input, the processing unit 11 acquires the power output voltage from the power supply unit 15, and converts the AC / DC conversion voltage and AC / DC from the analog / digital converter A / D. The conversion current is acquired and stored as the power supply output voltage 12E1, the AC / DC conversion voltage 12E2 and the AC / DC conversion current 12E3 of the measurement data 12E in the storage unit 12 (S301). Next, the measurement data 12E held for several times is read from the storage unit 12, and the temporal change of the measurement data 12E is displayed on the display unit 13 (S302).

  FIG. 4 is a diagram showing a screen on which a temporal change in the output voltage value is displayed as a graph. FIG. 4A shows a recent trend (time change) of the output voltage value of the power supply unit 15. FIG. 4B shows a trend of the output voltage value of the power supply unit 15 when a failure has occurred in the past. Of the past data 12F in the storage unit 12, data included in the failure data 12F2 is used. It is done. FIG. 4C shows the trend of the output voltage value of the recent analog-digital converter A / D. FIG. 4D shows a trend of the output voltage value of the analog-to-digital converter A / D when a failure has occurred in the past, and is included in the failure data 12F2 in the past data 12F of the storage unit 12. Data is used. Note that the screens of FIGS. 4A to 4D may be switched and displayed by an operator's operation, or may be displayed together on one screen.

  The manager of the protective relay 1 may refer to the current trend (first data group) displayed on the display unit 12 and determine whether the protective relay 1 is normal or likely to fail due to his / her insight. The determination may be made by comparing the current trend displayed on the display unit 12 with the trend at the time of failure that has occurred in the past (second data group).

  Subsequently, the processing unit 11 of the protective relay 1 collates the measurement data 12E stored in the storage unit 12 with the past data 12F (S303). As a result of the collation, when there is past data 12F similar to the measurement data 12E and the similar past data 12F is the fault data 12F2 (Y in S304), a message is displayed to warn of the possibility of the fault occurrence. The information is displayed on the unit 13 (S305). If there is no similar past data 12F or the similar past data 12F is normal data 12F1 (N in S304), the process of S305 is skipped. If the similar past data 12F is normal data 12F1, it may be determined that the data is in a normal state at the present time, and that fact may be displayed on the display unit 13. If there is data in the normal data 12F1 or the failure data 12F2 that has a correlation greater than or equal to a predetermined value, priority is given to the processing when there is similar data in the failure data 12F2, and a failure occurs. Warn of the possibility of

  Here, “similar” means that a correlation of a predetermined level or more is recognized between the current trend and the past trend. For example, a correlation coefficient between two trends is calculated and the correlation is calculated. When the correlation coefficient is equal to or greater than a predetermined reference value, it is determined that they are similar. If a correlation is recognized between the two trends, the current situation is “before failure” and a failure is predicted to occur after a while. In calculating the correlation coefficient, the correlation coefficient is calculated while shifting the time axis between the current trend and the past trend. As a result, the largest calculated value is adopted as the correlation coefficient between the two trends. May be.

  The failure content will be described in detail. When the power supply output voltage 12E1 is similar to the failure data 12F2 in the measurement data 12E, it indicates that the failure of the power supply unit 15 is predicted. At this time, there is a possibility that the entire protective relay 1 may not operate, and a warning is given that the power supply unit 15 needs to be replaced. Further, in the measurement data 12E, when the AC / DC conversion voltage 12E2 is similar to the failure data 12F2, the result of converting the AC voltage of the power transmission system L1 into the DC voltage is within a range of 0 to 5V which is a normal value. Indicates that it is coming off. At this time, a warning is given that the accident detection capability of the protective relay 1 is decreasing and the AC / DC converter IT2 and the like need to be replaced. Furthermore, not only a warning that indicates the possibility of a failure, but also a predicted failure time based on a past failure trend that is similar to the current trend. May be displayed on the display unit 12. For example, a predicted failure occurrence time can be obtained by subtracting the time corresponding to the current time in the past trend from the failure occurrence time in the past and adding the subtracted time to the current time. .

  Next, the processing unit 11 of the protective relay 1 determines whether or not new inspection data 12D is stored in the storage unit 12 (S306). This is the data obtained by the inspection using the test apparatus 2 as the inspection data 12D, and since the acquisition interval is longer than the measurement data 12E of S301, it is confirmed whether or not the inspection data 12D has been updated. . If there is new inspection data 12D (Y in S306), the temporal change of the inspection data 12D is displayed on the display unit 13 (S307). The manager of the protective relay 1 may refer to the temporal change of the inspection data 12D to judge whether it is normal or likely to become a failure by its own insight, and the current trend and the failure that has occurred in the past You may judge by comparing with the trend of time.

  Subsequently, the processing unit 11 of the protective relay 1 determines whether there is inspection data 12D that is highly likely to deviate from the set value data 12C (S308). If the corresponding inspection data 12D is present (Y in S308), the display unit 13 is displayed to warn of the possibility of failure or that the set value needs to be reviewed (S309), and the process returns to S301. . Here, “deviation” means that it is not included between ± α (α: predetermined value) from the set value, and “probable to deviate” means the time until that point. When the change is extended and a future value is predicted, it is judged that there is a high possibility that the difference from the settling value will be larger than α. For example, in the inspection data 12D, the possibility that the test current 12D1 or the test voltage 12D2 deviates from the set value is that the current or voltage at which the protective relay 1 operates is too small or too large. Thus, after a while, the difference from the settling value is predicted to exceed α, indicating that the protective relay 1 reacts sensitively or bluntly. At this time, a warning is given that the accident detection capability of the protective relay 1 is decreasing or that the set value needs to be reviewed. Further, in the inspection data 12D, the operation time 12D4 is likely to deviate from the set value because the time from when the test current or the test voltage is input to the protective relay 1 until the interruption command is issued is long, It shows that after a while, the difference from the settling value is expected to be longer than α. At this time, a warning is given that the interruption command signal to the circuit breaker 3 may be delayed. As with the measurement data 12E, the inspection data 12D retains data from the start of the operation of the protective relay 1 or the start of re-operation due to failure recovery, and compares and collates the current trend with the past trend. Thus, the presence or absence of correlation may be determined. In this case, for example, the operation time 12D4 tends to gradually increase with time.

  When there is no new inspection data 12D (N in S306) or there is no inspection data 12D that is likely to deviate from the set value (N in S308), the processing unit 11 of the protective relay 1 performs the processing in S309. Skip and return to S301.

  In the above embodiment, in order to make each component in the protective relay 1 shown in FIG. 1 function, a program executed by the processing unit 11 is recorded on a computer-readable recording medium, and the recorded program is recorded. It is assumed that the protection relay 1 according to the embodiment of the present invention is realized by being read and executed by a computer. In this case, the program may be provided to the computer via a network such as the Internet, or a semiconductor chip or the like in which the program is written may be incorporated in the computer.

  According to the embodiment of the present invention described above, the failure of the protective relay 1 can be grasped in advance. Since the inspection record is stored in the storage unit 12 of the protective relay 1, complicated filing work in the office can be eliminated. Inspection data 12D and measurement data 12E for a recent predetermined period are stored, and past data 12F is further stored, so that the characteristic tendency of each part can be grasped easily and in detail.

<< Other embodiments >>
As mentioned above, although the form for implementing this invention was demonstrated, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof. For example, the following embodiments can be considered.

(1) In the above embodiment, the measurement data 12E and the inspection data 12D are compared and collated with the past data 12F, and when they are similar, it is determined whether the similar past data is fault data. Although described, not only one item but two items or more items may be NG, it may be predicted that there is a possibility of failure. Further, it may be predicted that there is a possibility of a failure when, for example, all of the determinations are NG in three or more determinations with a predetermined time interval instead of a single determination. According to this, in any case, the possibility of erroneous determination can be eliminated and the reliability of failure determination can be improved.

(2) In the above embodiment, the past data 12F stored in the storage unit 15 of the protective relay 1 is described as being divided into normal data 12F1 and failure data 12F2. However, the past data 12F is stored in another format. It may be. For example, data such as output voltage in the past may be stored in time series, and the time when a failure has occurred in a component such as the power supply unit 5 may be stored. In this case, if there is a portion similar to the current trend (measurement data 12E) in the past time-series data and a failure of a part related to the data has occurred after that portion, the current failure is Pre-occurrence "and predicts that there is a possibility of failure of the part soon. On the other hand, if there is a part similar to the current trend in the past time-series data, and if there is no failure of the part related to the data after that part, it is determined that the part is normal.

(3) In the above embodiment, the current trend and the warning of failure occurrence are described to be displayed on the display unit 13 of the protective relay 1. However, they may be output to other devices. For example, it may be displayed on a large main monitor installed in the vicinity of the protective relay 1 or transmitted to a mobile phone or PDA (Personal Digital Assistants) owned by the administrator of the protective relay 1 via a network. May be.

DESCRIPTION OF SYMBOLS 1 Protection relay 11 Processing part 12 Storage part 12D Inspection data (data, 1st data group)
12D1 Test current 12D2 Test voltage 12D4 Operating time 12E Measurement data (data, first data group)
12E1 Power supply output voltage (Power supply output voltage)
12E2 AC / DC conversion voltage (voltage obtained by converting AC voltage of transmission system to DC)
12F Past data (data, second data group)
12F1 Normal data 12F2 Failure data (failure)

Claims (5)

A protective relay,
Data that is periodically acquired to check the operation of the protective relay is stored as time-series data, and a failure occurs when a failure occurs in the protective relay after the time-series data is acquired. Means for storing data indicating this in association with the time-series data;
Of the stored time-series data, a first data group including time-series data after a predetermined period before the latest data acquisition time point and second data including time-series data other than the first data group Means for determining whether or not there is a correlation of a predetermined degree or more with the group;
Data indicating that there is a correlation between the first data group and the second data group and that the failure has occurred is stored in association with time-series data included in the second data group. A means for predicting that the protective relay may fail if
A protective relay comprising: The protective relay according to claim 1,
The protective relay further comprising means for outputting that the protective relay is predicted to be likely to fail. A protective relay according to claim 2,
Based on the time of the first data group, the time of the second data group, and the time of failure of the protective relay after the second data group, the time of failure of the protective relay is determined in the future. Means to predict,
Means for outputting a time when the predicted failure of the protective relay occurs;
A protective relay, further comprising: A protective relay according to any one of claims 1 to 3,
Data indicating that there is the correlation between the first data group and the second data group and that the failure has occurred is stored in association with time-series data included in the second data group. If not, the protective relay further comprises means for determining that the protective relay is normal. A protective relay according to any one of claims 1 to 4,
The data is an output voltage of a power source, a voltage obtained by converting an alternating voltage of a power transmission system into a direct current, a test current, a test voltage, or an operation time.

Images