Method and device for determining the ageing degree of a relay protection device

Abstract

A method and device for determining the aging degree of a relay protection device, the method comprising: obtaining temperatures of a plurality of relay protection devices; obtaining a plurality of ambient temperatures according to the temperatures of the plurality of relay protection devices and a mapping relationship between the ambient temperature and the temperature of each relay protection device; calculating an average value of the plurality of ambient temperatures to obtain an average ambient temperature; calibrating the temperatures of the plurality of relay protection devices according to the average ambient temperature to obtain nominal device temperatures of the plurality of relay protection devices; judging whether the absolute value of the nominal device temperature of each relay protection device is within a normal range; and determining whether each relay protection device has an aging anomaly according to the judgment result. Through the method and device provided in the embodiments of the present application, the aging degree of the relay protection device can be evaluated online only by relying on the temperature of the relay protection device, and the aging degree monitoring and early troubleshooting of the relay protection device can be realized.

Description

Technical Field

[0001] This invention relates to the field of power system relay protection, and more specifically, to a method and apparatus for determining the aging degree of a relay protection device. Background Technology

[0002] Relay protection devices not only ensure the normal operation of the power system, but also provide protection for various equipment and components within the system. Failure of a relay protection device can have a significant impact on the entire power system. Therefore, ensuring the reliability of relay protection devices is a crucial aspect of guaranteeing the safe and stable operation of the power grid.

[0003] The aging failure theory of relay protection devices posits that electronic component failure typically begins with the accumulation of linear fatigue, leading to a deterioration in the device's operating condition and ultimately resulting in nonlinear accelerated damage. Failure is usually determined by severe anomalies such as device blocking, often accompanied by a sudden deterioration in internal variables (internal temperature, power supply voltage, etc.). Therefore, analyzing the aging degree of relay protection devices and promptly identifying those with abnormal aging helps to quickly eliminate protection defects, improve protection availability, and prevent the escalation of accidents caused by aging protection devices during power grid faults.

[0004] Currently, the temperature status of relay protection devices is typically monitored manually, which presents a challenge in timely detecting abnormal aging of these devices. Online monitoring of the internal temperature of relay protection devices creates conditions for online analysis of their aging levels. However, relay protection devices only transmit their internal temperature data, not the ambient temperature. Therefore, certain technical means are needed to indirectly obtain the ambient temperature to achieve online analysis of the device's aging degree. Summary of the Invention

[0005] In view of this, the present invention proposes a method and apparatus for determining the aging degree of relay protection devices, aiming to solve the problem of difficulty in detecting aging abnormalities of relay protection devices in related technologies.

[0006] In a first aspect, embodiments of the present invention provide a method for determining the aging degree of a relay protection device, characterized in that the method includes: acquiring the temperatures of a plurality of relay protection devices; obtaining a plurality of ambient temperatures based on the temperatures of the plurality of relay protection devices and a pre-established mapping relationship between ambient temperature and the temperature of each relay protection device; calculating the average value of the plurality of ambient temperatures to obtain an average ambient temperature; calibrating the temperatures of the plurality of relay protection devices based on the average ambient temperature to obtain nominal device temperatures of the plurality of relay protection devices; determining whether the absolute value of the nominal device temperature of each relay protection device is within the normal range; and determining whether each relay protection device exhibits abnormal aging based on the determination result.

[0007] Furthermore, the mapping relationship between the ambient temperature and the temperature of each relay protection device is established in advance using the following method: The ambient temperature at each historical sampling time and the temperature of each relay protection device at each historical sampling time are fitted to obtain the following formula: T dk =Δ k +b k T e Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e For ambient temperature, Δ k b is the first parameter k This is the second parameter.

[0008] Furthermore, the Δ k b k The following formulas are used to obtain the results:

[0009] Δ k =T' dk -b k T' e ;

[0010]

[0011] Where L represents the number of historical samples, and T dk(i) T e(i) Let T' be the i-th sampled value of the temperature of the k-th relay protection device and the i-th sampled value of the ambient temperature, respectively. dk T' is the average value of the historical sampling temperature of the k-th relay protection device over L times. e This represents the average ambient temperature from L historical samplings.

[0012] Furthermore, after calculating the average value of the plurality of ambient temperatures to obtain the average ambient temperature, the method further includes: determining whether each of the ambient temperatures is within the normal range; if so, the average ambient temperature is taken as the final average ambient temperature; otherwise, ambient temperatures that are not within the normal range are removed, the average ambient temperature is recalculated, and the determination of whether each ambient temperature is within the normal range is continued; this process is repeated until each ambient temperature is within the normal range.

[0013] Further, calculating the average of the plurality of ambient temperatures to obtain the average ambient temperature includes: calculating the average ambient temperature μ using the following formula:

[0014]

[0015] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer. k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0016] Furthermore, determining whether each ambient temperature is within the normal range includes: determining whether each ambient temperature is within μ±1.96σ. k Within the range; among which, R k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0017] Further, the step of calibrating the temperatures of the plurality of relay protection devices based on the average ambient temperature to obtain the nominal device temperatures of the plurality of relay protection devices includes: calculating the nominal device temperature f of the relay protection device using the following formula. k :f k =T dk -b k T e -Δ k Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e Δ represents the average ambient temperature. k b is the first parameter k This is the second parameter.

[0018] Furthermore, determining whether the absolute value of the nominal device temperature of each of the relay protection devices is within the normal range includes determining whether the absolute value of the nominal device temperature of each of the relay protection devices is within the range of 0-5℃.

[0019] Secondly, embodiments of the present invention also provide an apparatus for determining the aging degree of relay protection devices, characterized in that the apparatus comprises: a relay protection device temperature acquisition unit for acquiring the temperature of a plurality of relay protection devices; an ambient temperature calculation unit for obtaining a plurality of ambient temperatures based on the temperatures of the plurality of relay protection devices and a pre-established mapping relationship between ambient temperature and the temperature of each relay protection device; an average ambient temperature calculation unit for calculating the average value of the plurality of ambient temperatures to obtain an average ambient temperature; a nominal device temperature calculation unit for calibrating the temperatures of the plurality of relay protection devices based on the average ambient temperature to obtain a nominal device temperature of the plurality of relay protection devices; a judgment unit for judging whether the absolute value of the nominal device temperature of each relay protection device is within the normal range; and an aging degree determination unit for determining whether each relay protection device exhibits abnormal aging based on the judgment result.

[0020] Furthermore, the mapping relationship between the ambient temperature and the temperature of each relay protection device is established in advance using the following method: The ambient temperature at each historical sampling time and the temperature of each relay protection device at each historical sampling time are fitted to obtain the following formula: T dk =Δ k +b k T e Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e For ambient temperature, Δ k b is the first parameter k This is the second parameter.

[0021] Furthermore, the Δ k b k The following formulas are used to obtain the results:

[0022] Δ k =T' dk -b k T' e ;

[0023]

[0024] Where L represents the number of historical samples, and T dk(i) T e(i) Let T' be the i-th sampled value of the temperature of the k-th relay protection device and the i-th sampled value of the ambient temperature, respectively. dk T' is the average value of the historical sampling temperature of the k-th relay protection device over L times. e This represents the average ambient temperature from L historical samplings.

[0025] Furthermore, the device also includes an outlier removal unit, used to calculate the average value of the plurality of ambient temperatures, and after obtaining the average ambient temperature, to determine whether each of the ambient temperatures is within the normal range; if so, the average ambient temperature is used as the final average ambient temperature; otherwise, the ambient temperatures that are not within the normal range are removed, the average ambient temperature is recalculated, and the determination of whether each ambient temperature is within the normal range is continued; this process is repeated until each ambient temperature is within the normal range.

[0026] Furthermore, the average ambient temperature calculation unit is also used to calculate the average ambient temperature μ using the following formula:

[0027]

[0028] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer. k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0029] Furthermore, determining whether each ambient temperature is within the normal range includes: determining whether each ambient temperature is within μ±1.96σ. k Within the range; among which, R k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0030] Furthermore, the nominal device temperature calculation unit is also used to: calculate the nominal device temperature f of the relay protection device using the following formula. k :f k =T dk -b k T e -Δ k Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e Δ represents the average ambient temperature. k b is the first parameter k This is the second parameter.

[0031] Furthermore, the judgment unit is also used to determine whether the absolute value of the nominal device temperature of each of the relay protection devices is within the range of 0-5℃.

[0032] Thirdly, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, characterized in that the program, when executed by a processor, implements the methods provided in the embodiments of the present invention.

[0033] The method and apparatus for determining the aging degree of relay protection devices provided in this invention obtain the ambient temperature based on the temperature of the relay protection device and a pre-established mapping relationship between the ambient temperature and the temperature of each relay protection device. Then, based on the obtained ambient temperature, the temperature of each relay protection device is calibrated to obtain a nominal device temperature used to determine the degree of abnormal aging of each relay protection device. This solves the problem of difficulty in detecting abnormal aging of relay protection devices, enabling online assessment of the aging degree of relay protection devices solely based on their temperature, thus achieving monitoring and early detection of the aging degree of relay protection devices. Attached Figure Description

[0034] Figure 1 An exemplary flowchart of a method for determining the aging degree of a relay protection device according to an embodiment of the present invention is shown;

[0035] Figure 2 The temperature change curves of four relay protection devices and ambient temperature according to an embodiment of the present invention are shown.

[0036] Figure 3 The nominal device temperature variation curves of four relay protection devices according to an embodiment of the present invention are shown, wherein (a) is the nominal device temperature variation curve of relay protection devices PM5001A and PM5001B, and (b) is the nominal device temperature variation curve of relay protection devices PM5002A and PM5002B.

[0037] Figure 4 A schematic diagram of a device for determining the aging degree of a relay protection device according to an embodiment of the present invention is shown. Detailed Implementation

[0038] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0039] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0040] Figure 1An exemplary flowchart of a method for determining the aging degree of a relay protection device according to an embodiment of the present invention is shown.

[0041] like Figure 1 As shown, the method includes:

[0042] Step S101: Obtain the temperature of several relay protection devices.

[0043] In this embodiment of the invention, there may be one, two, or more relay protection devices, and they may be relay protection devices of the same cabinet. The temperature of each relay protection device is the online temperature obtained by the acquisition device.

[0044] Step S102: Based on the temperatures of several relay protection devices and the pre-established mapping relationship between ambient temperature and the temperature of each relay protection device, several ambient temperatures are obtained.

[0045] In this embodiment of the invention, the mapping relationship between ambient temperature and the temperature of each relay protection device is generally linear, and can be specifically obtained by fitting historical data. Since each relay protection device temperature has a corresponding mapping relationship with the ambient temperature, several ambient temperatures corresponding to the temperatures of several relay protection devices can be obtained based on the temperatures of several relay protection devices.

[0046] Furthermore, the mapping relationship between ambient temperature and the temperature of each relay protection device is established in advance using the following method:

[0047] By fitting the ambient temperature and the temperature of each relay protection device at each historical sampling time, the following formula is obtained:

[0048] T dk =Δ k +b k T e ;

[0049] Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e For ambient temperature, Δ k b is the first parameter k This is the second parameter.

[0050] In this embodiment of the invention, the first parameter Δ k The second parameter b k All of these are related to the performance of the relay protection device itself; different relay protection devices have different Δ values. k b k .

[0051] Furthermore, Δ k b kThe following formulas are used to obtain the results:

[0052] Δ k =T' dk -b k T' e ;

[0053]

[0054] Where L represents the number of historical samples, and T dk(i) T e(i) Let T' be the i-th sampled value of the temperature of the k-th relay protection device and the i-th sampled value of the ambient temperature, respectively. dk T' is the average value of the historical sampling temperature of the k-th relay protection device over L times. e This represents the average ambient temperature from L historical samplings.

[0055] In this embodiment of the invention, for the k-th relay protection device, based on the ambient temperature T at the i-th historical sampling time... e(i) Temperature T of relay protection device dk(i) , get T dk(i) =Δ k +b k T e(i) By fitting data from L historical sampling times, the ambient temperature T can be obtained. e Temperature T of the kth relay protection device dk Mapping relationship T dk =Δ k +b k T e .

[0056] The above embodiments, by fitting historical data of ambient temperature with the temperature of each relay protection device, obtain the mapping relationship between ambient temperature and the temperature of each relay protection device. This solves the problem that the current online device temperature does not have a corresponding online ambient temperature, which makes it impossible to achieve real-time assessment of the aging status of relay protection devices. It can achieve accurate assessment of the aging degree of relay protection devices.

[0057] Step S103: Calculate the average value of several ambient temperatures to obtain the average ambient temperature.

[0058] Further, step S103 includes:

[0059] The average ambient temperature μ is calculated using the following formula:

[0060]

[0061] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer.k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0062] In this embodiment of the invention, T ek It can be made by T ek =(T dk -Δ k ) / b k Calculations show that T dk The temperature of the kth relay protection device.

[0063] Furthermore, after calculating the average of several ambient temperatures and obtaining the average ambient temperature, the process also includes:

[0064] Determine whether each ambient temperature is within the normal range;

[0065] If so, the average ambient temperature will be used as the final average ambient temperature.

[0066] Otherwise, after removing ambient temperatures that are outside the normal range, the average ambient temperature is recalculated, and it is continued to determine whether each ambient temperature is within the normal range.

[0067] Repeat this process until each ambient temperature is within the normal range.

[0068] Furthermore, determine whether each ambient temperature is within the normal range, including:

[0069] Determine whether each ambient temperature is within μ±1.96σ. k Within the range;

[0070] in, R k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0071] In this embodiment of the invention, elements not in [μ-1.96σ] are removed. k μ+1.96σ k After determining the ambient temperature within the range of [μ-1.96σ], the average ambient temperature μ is recalculated, and it is further determined whether each ambient temperature falls within [μ-1.96σ]. k μ+1.96σ k Repeat this process within the range of [μ-1.96σ] until each ambient temperature is within [μ-1.96σ]. k μ+1.96σ k End within the specified range.

[0072] The above embodiments, by eliminating ambient temperatures outside the normal range, avoid the problem of inaccurate ambient temperatures inferred due to the aging of individual relay protection devices, thus ensuring the accuracy and reliability of relay protection device aging assessment.

[0073] Step S104: Based on the average ambient temperature, calibrate the temperature of several relay protection devices to obtain the nominal device temperature of several relay protection devices.

[0074] Further, step S104 includes:

[0075] The nominal device temperature f of the relay protection device is calculated using the following formula. k :

[0076] f k =T dk -b k T e -Δ k ;

[0077] Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e Δ represents the average ambient temperature. k b is the first parameter k This is the second parameter.

[0078] In this embodiment of the invention, T e The average ambient temperature can be obtained by weighted averaging of each ambient temperature, or by using the following formula.

[0079] T e =μ;

[0080]

[0081] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer. k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0082] In some embodiments of the present invention, T e It can be the average value of all ambient temperatures within the normal range after removing ambient temperatures that are outside the normal range.

[0083] The above embodiments calibrate the temperature of the relay protection device to obtain a nominal device temperature f that removes the influence of ambient temperature, device structure, and installation conditions, and can be used to uniformly evaluate the status of the relay protection device. k .

[0084] Step S105: Determine whether the absolute value of the nominal device temperature of each relay protection device is within the normal range.

[0085] Further, step S105 includes:

[0086] Determine whether the absolute value of the nominal device temperature of each relay protection device is within the range of 0-5℃.

[0087] Step S106: Based on the judgment results, determine whether each relay protection device has aging abnormalities.

[0088] In this embodiment of the invention, if the absolute value of the nominal device temperature of the relay protection device is within the normal range, preferably 0-5℃, it indicates that the relay protection device has not experienced aging abnormalities; otherwise, it indicates that the relay protection device has experienced aging abnormalities.

[0089] In the above embodiments, the ambient temperature is obtained by using the temperature of the relay protection device and a pre-established mapping relationship between the ambient temperature and the temperature of each relay protection device. Based on the obtained ambient temperature, the temperature of each relay protection device is calibrated to obtain the nominal device temperature used to determine the degree of aging abnormality of each relay protection device. This solves the problem of difficulty in detecting aging abnormalities of relay protection devices. It enables online assessment of the aging degree of relay protection devices based solely on the temperature of the relay protection devices, and realizes the monitoring and early detection of the aging degree of relay protection devices.

[0090] It is important to understand that the aging of relay protection devices follows a pattern of slow, gradual accumulation over a long period, followed by rapid aging and failure. Only by monitoring the aging process online can potential aging problems be detected in a timely manner. However, it is difficult to collect ambient temperature information synchronously with device temperature information, which restricts the realization of real-time assessment of the aging degree of relay protection devices. To address this, this invention fully utilizes the correlation between relay protection device temperature and ambient temperature, proposing a method to indirectly reflect changes in ambient temperature by using the temperatures of other relay protection devices within the same cabinet. Considering that the possibility of multiple relay protection devices aging simultaneously is extremely low, when a relay protection device ages abnormally, its temperature increases relative to other relay protection devices compared to historical data. By monitoring this increase, abnormal aging signs can be detected in a timely manner, enabling monitoring and early detection of the aging degree of relay protection devices.

[0091] Example 1

[0092] Two sets of relay protection devices (labeled PM5001A, PM5001B, PM5002A, and PM5002B, with k values ​​of 1, 2, 3, and 4 respectively) are arranged nearby at each of the #1M and #2M sections of a 500kV intelligent substation. The online temperature of the relay protection devices is read, and the aging degree is assessed according to the steps of this embodiment of the invention.

[0093] (1) Using least squares estimation, the mapping relationship between the temperature of the four relay protection devices and the ambient temperature was fitted. The results are as follows:

[0094] T d1=Δ1+b1T e =13.042℃+T e

[0095] T d2 =Δ2+b2T e =26.561℃+T e

[0096] T d3 =Δ3+b3T e =11.149℃+T e

[0097] T d4 =Δ4+b4T e =24.542℃+T e

[0098] (2) Determine the ambient temperature. Figure 2 The diagram illustrates the temperature variation curves of four relay protection devices and the ambient temperature according to an embodiment of the present invention. Figure 2 As shown, taking 00:00 on July 9th as an example, the ambient temperature is deduced by reading the temperature of the relay protection devices. The ambient temperature T is then calculated by deducing the temperature from the temperatures of the four relay protection devices. ek The temperatures (k=1,…,4) are 26.458℃, 26.359℃, 26.451℃, and 26.338℃, respectively. The variances of the temperature measurement noise of the four relay protection devices are 0.3. 2 0.1 2 0.3 2 0.1 2 .application The calculated value is μ = 26.359℃. After verification, the T value of the four relay protection devices is... ek All within μ±1.96σ k Within the range, the ambient temperature T at 0:00 e The temperature was 26.359℃. Ambient temperatures at other times were obtained using the same method.

[0099] (3) Figure 3 The diagram shows the nominal device temperature variation curves of four relay protection devices according to an embodiment of the present invention. (See diagram for reference.) Figure 3 As shown, press f k =T dk -b k T e -Δ k The temperature of the device is calibrated to obtain the nominal device temperature f. k .

[0100] (4) Determine the aging status of the four relay protection devices based on their nominal device temperatures. For example... Figure 3As shown, the nominal device temperature of the four relay protection devices is within ±5℃, so the four protection devices have not shown any signs of aging.

[0101] Figure 4 A schematic diagram of a device for determining the aging degree of a relay protection device according to an embodiment of the present invention is shown.

[0102] like Figure 4 As shown, the device includes:

[0103] The relay protection device temperature acquisition unit 401 is used to acquire the temperature of several relay protection devices.

[0104] In this embodiment of the invention, there may be one, two, or more relay protection devices, and they may be relay protection devices of the same cabinet. The temperature of each relay protection device is the online temperature obtained by the acquisition device.

[0105] The ambient temperature calculation unit 402 is used to obtain several ambient temperatures based on the temperatures of several relay protection devices and the pre-established mapping relationship between ambient temperature and the temperature of each relay protection device.

[0106] In this embodiment of the invention, the mapping relationship between ambient temperature and the temperature of each relay protection device is generally linear, and can be specifically obtained by fitting historical data. Since each relay protection device temperature has a corresponding mapping relationship with the ambient temperature, several ambient temperatures corresponding to the temperatures of several relay protection devices can be obtained based on the temperatures of several relay protection devices.

[0107] Furthermore, the mapping relationship between ambient temperature and the temperature of each relay protection device is established in advance using the following method:

[0108] By fitting the ambient temperature and the temperature of each relay protection device at each historical sampling time, the following formula is obtained:

[0109] T dk =Δ k +b k T e ;

[0110] Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e For ambient temperature, Δ k b is the first parameter k This is the second parameter.

[0111] In this embodiment of the invention, the first parameter Δ k The second parameter b kAll of these are related to the performance of the relay protection device itself; different relay protection devices have different Δ values. k b k .

[0112] Furthermore, Δ k b k The following formulas are used to obtain the results:

[0113] Δ k =T' dk -b k T' e ;

[0114]

[0115] Where L represents the number of historical samples, and T dk(i) T e(i) Let T' be the i-th sampled value of the temperature of the k-th relay protection device and the i-th sampled value of the ambient temperature, respectively. dk T' is the average value of the historical sampling temperature of the k-th relay protection device over L times. e This represents the average ambient temperature from L historical samplings.

[0116] In this embodiment of the invention, for the k-th relay protection device, based on the ambient temperature T at the i-th historical sampling time... e(i) Temperature T of relay protection device dk(i) , get T dk(i) =Δ k +b k T e(i) By fitting data from L historical sampling times, the ambient temperature T can be obtained. e Temperature T of the kth relay protection device dk Mapping relationship T dk =Δ k +b k T e .

[0117] The above embodiments, by fitting historical data of ambient temperature with the temperature of each relay protection device, obtain the mapping relationship between ambient temperature and the temperature of each relay protection device. This solves the problem that the current online device temperature does not have a corresponding online ambient temperature, which makes it impossible to achieve real-time assessment of the aging status of relay protection devices. It can achieve accurate assessment of the aging degree of relay protection devices.

[0118] The average ambient temperature calculation unit 403 is used to calculate the average value of several ambient temperatures to obtain the average ambient temperature.

[0119] Furthermore, the average ambient temperature calculation unit 403 is also used for:

[0120] The average ambient temperature μ is calculated using the following formula:

[0121]

[0122] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer. k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0123] In this embodiment of the invention, T ek It can be made by T ek =(T dk -Δ k ) / b k Calculations show that T dk The temperature of the kth relay protection device.

[0124] Furthermore, the device also includes:

[0125] The outlier removal unit is used to calculate the average value of several ambient temperatures. After obtaining the average ambient temperature, it determines whether each ambient temperature is within the normal range.

[0126] If so, the average ambient temperature will be used as the final average ambient temperature.

[0127] Otherwise, after removing ambient temperatures that are outside the normal range, the average ambient temperature is recalculated, and it is continued to determine whether each ambient temperature is within the normal range.

[0128] Repeat this process until each ambient temperature is within the normal range.

[0129] Furthermore, determine whether each ambient temperature is within the normal range, including:

[0130] Determine whether each ambient temperature is within μ±1.96σ. k Within the range;

[0131] in, R k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0132] In this embodiment of the invention, elements not in [μ-1.96σ] are removed. k μ+1.96σ k After determining the ambient temperature within the range of [μ-1.96σ], the average ambient temperature μ is recalculated, and it is further determined whether each ambient temperature falls within [μ-1.96σ]. k μ+1.96σ k Repeat this process within the range of [μ-1.96σ] until each ambient temperature is within [μ-1.96σ]. kμ+1.96σ k End within the specified range.

[0133] The above embodiments, by eliminating ambient temperatures outside the normal range, avoid the problem of inaccurate ambient temperatures inferred due to the aging of individual relay protection devices, thus ensuring the accuracy and reliability of relay protection device aging assessment.

[0134] The nominal device temperature calculation unit 404 is used to calibrate the temperature of several relay protection devices based on the average ambient temperature, so as to obtain the nominal device temperature of several relay protection devices.

[0135] Furthermore, the nominal device temperature calculation unit 404 is also used for:

[0136] The nominal device temperature f of the relay protection device is calculated using the following formula. k :

[0137] f k =T dk -b k T e -Δ k ;

[0138] Among them, T dk Let T be the temperature of the k-th relay protection device, k = 1, ..., M, where M is a positive integer. e Δ represents the average ambient temperature. k b is the first parameter k This is the second parameter.

[0139] In this embodiment of the invention, T e The average ambient temperature can be obtained by weighted averaging of each ambient temperature, or by using the following formula.

[0140] T e =μ;

[0141]

[0142] Among them, T ek Let R be the k-th ambient temperature, k = 1, ..., M, where M is a positive integer. k Let V be the variance of the temperature measurement noise of the k-th relay protection device.

[0143] In some embodiments of the present invention, T e It can be the average value of all ambient temperatures within the normal range after removing ambient temperatures that are outside the normal range.

[0144] The above embodiments calibrate the temperature of the relay protection device to obtain a nominal device temperature f that removes the influence of ambient temperature, device structure, and installation conditions, and can be used to uniformly evaluate the status of the relay protection device. k .

[0145] The judgment unit 405 is used to determine whether the absolute value of the nominal device temperature of each relay protection device is within the normal range.

[0146] Furthermore, the judgment unit 405 is also used for:

[0147] Determine whether the absolute value of the nominal device temperature of each relay protection device is within the range of 0-5℃.

[0148] The aging degree determination unit 406 is used to determine whether each relay protection device has aging abnormalities based on the judgment result.

[0149] In this embodiment of the invention, if the absolute value of the nominal device temperature of the relay protection device is within the normal range, preferably 0-5℃, it indicates that the relay protection device has not experienced aging abnormalities; otherwise, it indicates that the relay protection device has experienced aging abnormalities.

[0150] In the above embodiments, the ambient temperature is obtained by using the temperature of the relay protection device and a pre-established mapping relationship between the ambient temperature and the temperature of each relay protection device. Based on the obtained ambient temperature, the temperature of each relay protection device is calibrated to obtain the nominal device temperature used to determine the degree of aging abnormality of each relay protection device. This solves the problem of difficulty in detecting aging abnormalities of relay protection devices. It enables online assessment of the aging degree of relay protection devices based solely on the temperature of the relay protection devices, and realizes the monitoring and early detection of the aging degree of relay protection devices.

[0151] It is important to understand that the aging of relay protection devices follows a pattern of slow, gradual accumulation over a long period, followed by rapid aging and failure. Only by monitoring the aging process online can potential aging problems be detected in a timely manner. However, it is difficult to collect ambient temperature information synchronously with device temperature information, which restricts the realization of real-time assessment of the aging degree of relay protection devices. To address this, this invention fully utilizes the correlation between relay protection device temperature and ambient temperature, proposing a method to indirectly reflect changes in ambient temperature by using the temperatures of other relay protection devices within the same cabinet. Considering that the possibility of multiple relay protection devices aging simultaneously is extremely low, when a relay protection device ages abnormally, its temperature increases relative to other relay protection devices compared to historical data. By monitoring this increase, abnormal aging signs can be detected in a timely manner, enabling monitoring and early detection of the aging degree of relay protection devices.

[0152] Example 2

[0153] Two sets of relay protection devices (labeled PM5001A, PM5001B, PM5002A, and PM5002B, with k values ​​of 1, 2, 3, and 4 respectively) are arranged nearby at each of the #1M and #2M sections of a 500kV intelligent substation. The online temperature of the relay protection devices is read, and the aging degree is assessed according to the steps of this embodiment of the invention.

[0154] (1) Using least squares estimation, the mapping relationship between the temperature of the four relay protection devices and the ambient temperature was fitted. The results are as follows:

[0155] T d1 =Δ1+b1T e =13.042℃+T e

[0156] T d2 =Δ2+b2T e =26.561℃+T e

[0157] T d3 =Δ3+b3T e =11.149℃+T e

[0158] T d4 =Δ4+b4T e =24.542℃+T e

[0159] (2) Determine the ambient temperature. Figure 2 The diagram illustrates the temperature variation curves of four relay protection devices and the ambient temperature according to an embodiment of the present invention. Figure 2 As shown, taking 00:00 on July 9th as an example, the ambient temperature is deduced by reading the temperature of the relay protection devices. The ambient temperature T is then calculated by deducing the temperature from the temperatures of the four relay protection devices. ek The temperatures (k=1,…,4) are 26.458℃, 26.359℃, 26.451℃, and 26.338℃, respectively. The variances of the temperature measurement noise of the four relay protection devices are 0.3. 2 0.1 2 0.3 2 0.1 2 .application The calculated value is μ = 26.359℃. After verification, the T value of the four relay protection devices is... ek All within μ±1.96σ k Within the range, the ambient temperature T at 0:00 e The temperature was 26.359℃. Ambient temperatures at other times were obtained using the same method.

[0160] (3) Figure 3The diagram shows the nominal device temperature variation curves of four relay protection devices according to an embodiment of the present invention. (See diagram for reference.) Figure 3 As shown, press f k =T dk -b k T e -Δ k The temperature of the device is calibrated to obtain the nominal device temperature f. k .

[0161] (4) Determine the aging status of the four relay protection devices based on their nominal device temperatures. For example... Figure 3 As shown, the nominal device temperature of the four relay protection devices is within ±5℃, so the four protection devices have not shown any signs of aging.

[0162] The present invention also provides a computer-readable storage medium storing one or more programs that, when executed by one or more processors, implement any of the methods described above for determining the aging degree of a relay protection device.

[0163] The invention has been described with reference to a few embodiments. However, as will be known to those skilled in the art, and as defined in the appended claims, other embodiments besides those disclosed above fall equivalently within the scope of the invention.

[0164] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

[0165] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0166] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0167] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0168] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A method for determining the aging degree of a relay protection device, characterized in that, The method includes: Obtain the temperature of several relay protection devices; Based on the temperatures of the aforementioned relay protection devices and the pre-established mapping relationship between ambient temperature and the temperature of each relay protection device, several ambient temperatures are obtained. Calculate the average value of the aforementioned ambient temperatures to obtain the average ambient temperature; Based on the average ambient temperature, the temperatures of the plurality of relay protection devices are calibrated to obtain the nominal device temperatures of the plurality of relay protection devices; Determine whether the absolute value of the nominal device temperature of each of the relay protection devices is within the normal range; Based on the judgment results, determine whether each of the relay protection devices has aging abnormalities; The mapping relationship between the ambient temperature and the temperature of each relay protection device is established in advance using the following method: By fitting the ambient temperature and the temperature of each relay protection device at each historical sampling time, the following formula is obtained: T dk = Δ k + b k T e ； in, T dk For the first k The temperature of the relay protection device, k =1,…, M , M It is a positive integer. T e For ambient temperature, Δ k As the first parameter, b k This is the second parameter; The step of calculating the average of the plurality of ambient temperatures, and obtaining the average ambient temperature, further includes: Determine whether each of the stated ambient temperatures is within the normal range; If so, the average ambient temperature shall be taken as the final average ambient temperature; Otherwise, after removing ambient temperatures that are outside the normal range, the average ambient temperature is recalculated, and the determination of whether each ambient temperature is within the normal range is continued. Repeat this process until each ambient temperature is within the normal range. The step of calibrating the temperatures of the plurality of relay protection devices based on the average ambient temperature to obtain the nominal device temperatures of the plurality of relay protection devices includes: The nominal device temperature of the relay protection device is calculated using the following formula. f k : f k = T dk - b k T e - Δ k ； in, T dk For the first k The temperature of the relay protection device, k =1,…, M , M It is a positive integer. T e For ambient temperature, Δ k As the first parameter, b k This is the second parameter; The step of determining whether the absolute value of the nominal device temperature of each relay protection device is within the normal range includes: Determine whether the absolute value of the nominal device temperature of each of the relay protection devices is within the range of 0-5℃.

2. The method according to claim 1, characterized in that, The Δ k , b k The following formulas are used to obtain the results: Δ k = T’ dk - b k T’ e ； ； in, L For historical sampling times, T dk(i) , T e(i) The first k The temperature of the relay protection device i The first sampled value, the ambient temperature i Second sample value, T’ dk For the first k Taiwan relay protection device L The average of the historical sampling temperatures. T’ e for L The average of the ambient temperature from each historical sampling.

3. The method according to claim 1, characterized in that, The calculation of the average of the plurality of ambient temperatures to obtain the average ambient temperature includes: The average ambient temperature is calculated using the following formula. μ : ； in, T ek For the first k An ambient temperature, k =1,…, M , M It is a positive integer. R k For the first k The variance of temperature measurement noise in the relay protection device.

4. The method according to claim 3, characterized in that, The determination of whether each of the ambient temperatures is within the normal range includes: Determine whether each of the aforementioned ambient temperatures is within the range of Within the range; in, , R k For the first k The variance of temperature measurement noise in the relay protection device.

5. A device for determining the aging degree of a relay protection device, characterized in that, The device includes: The relay protection device temperature acquisition unit is used to acquire the temperature of several relay protection devices. An ambient temperature calculation unit is used to obtain several ambient temperatures based on the temperatures of the several relay protection devices and a pre-established mapping relationship between ambient temperature and the temperature of each relay protection device. An average ambient temperature calculation unit is used to calculate the average value of the plurality of ambient temperatures to obtain the average ambient temperature. The nominal device temperature calculation unit is used to calibrate the temperature of the plurality of relay protection devices based on the average ambient temperature, so as to obtain the nominal device temperature of the plurality of relay protection devices. The judgment unit is used to determine whether the absolute value of the nominal device temperature of each of the relay protection devices is within the normal range; An aging degree determination unit is used to determine, based on the judgment result, whether each of the relay protection devices has an aging abnormality; The outlier removal unit is used to calculate the average value of the several ambient temperatures. After obtaining the average ambient temperature, it determines whether each ambient temperature is within the normal range. If so, the average ambient temperature is used as the final average ambient temperature. Otherwise, the ambient temperatures that are not within the normal range are removed, the average ambient temperature is recalculated, and the determination of whether each ambient temperature is within the normal range is continued. This process is repeated until each ambient temperature is within the normal range. The mapping relationship between the ambient temperature and the temperature of each relay protection device is established in advance using the following method: By fitting the ambient temperature and the temperature of each relay protection device at each historical sampling time, the following formula is obtained: T dk = Δ k + b k T e ； in, T dk For the first k The temperature of the relay protection device, k =1,…, M , M It is a positive integer. T e For ambient temperature, Δ k As the first parameter, b k This is the second parameter; The nominal device temperature calculation unit is further used for: The nominal device temperature of the relay protection device is calculated using the following formula. f k : f k = T dk - b k T e - Δ k ； in, T dk For the first k The temperature of the relay protection device, k =1,…, M , M It is a positive integer. T e For ambient temperature, Δ k As the first parameter, b k This is the second parameter; The determination unit is further configured to: Determine whether the absolute value of the nominal device temperature of each of the relay protection devices is within the range of 0-5℃.

6. The apparatus according to claim 5, characterized in that, The Δ k , b k The following formulas are used to obtain the results: Δ k = T’ dk - b k T’ e ； ； in, L For historical sampling times, T dk(i) , T e(i) The first k The temperature of the relay protection device i The first sampled value, the ambient temperature i Second sample value, T’ dk For the first k Taiwan relay protection device L The average of the historical sampling temperatures. T’ e for L The average of the ambient temperature from each historical sampling.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-4.

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