A method and system for detecting degradation degree of lightning arrester

Abstract

The invention discloses a method and system for detecting the degradation degree of a lightning arrester, and belongs to the technical field of detecting the degradation degree of a lightning arrester. The method comprises the following steps: obtaining performance data of a lightning arrester subjected to a most recent impulse current, environmental data when the lightning arrester is subjected to the most recent impulse current, and the number of times the lightning arrester can withstand a maximum impulse current; inputting the performance data and environmental data into a trained lightning arrester degradation degree detection model to obtain the newly added degradation degree caused by the lightning arrester subjected to the most recent impulse current; calculating the number of times the lightning arrester can withstand the maximum impulse current based on the newly added degradation degree caused by the lightning arrester subjected to the most recent impulse current and the number of times the lightning arrester can withstand the maximum impulse current, and then dividing the number by the number of times the lightning arrester can withstand the maximum impulse current to obtain the degradation degree of the lightning arrester. The invention uses the newly added degradation degree during the most recent impulse to calculate the degradation degree of the lightning arrester, accurately reflects whether the lightning arrester can still withstand the impulse, and improves the detection accuracy.

Description

Technical Field

[0001] The invention relates to a method and a system for detecting the degradation degree of a lightning arrester, and belongs to the technical field of detecting the degradation degree of a lightning arrester. Background Art

[0002] The main function of the arrester is to protect the power supply line and the facilities on the line from shock by guiding the overvoltage on the power supply line to flow from itself to the earth. The arrester online monitoring device can monitor the arrester's leakage total current Ix, resistive current Ir, third, fifth, and seventh harmonics, impulse current and occurrence time, number of impulse currents, etc. The arrester will gradually deteriorate after long-term use. Usually, the arrester online monitoring device measures the arrester's leakage total current Ix, resistive current Ir, third, fifth, and seventh harmonics and other data to see if there are any abnormalities. Based on these, the arrester's degradation degree is judged and whether it needs to be replaced. After the arrester deteriorates, the data such as the total current Ix and resistive current Ir do not change significantly, and it is not easy to judge the degree of degradation. The best opportunity to replace the arrester is often missed, resulting in major accidents; it may also be replaced too early due to minor degradation, resulting in unnecessary waste. Summary of the invention

[0003] The object of the present invention is to provide a method and system for detecting the degradation degree of a lightning arrester, so as to solve the problem of low detection accuracy existing in the prior art.

[0004] To achieve the above objectives, the present invention is implemented by adopting the following technical solutions:

[0005] In a first aspect, the present invention provides a method for detecting the degradation degree of a lightning arrester, comprising:

[0006] Obtain the performance data of the most recent surge current that the arrester has been subjected to, the environmental data when it was subjected to the most recent surge current, and the number of times the arrester can withstand the maximum surge current;

[0007] Inputting the performance data and the environmental data into a trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current;

[0008] Based on the newly added deterioration degree of the arrester caused by the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, calculate the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the deterioration degree of the arrester;

[0009] The training of the arrester degradation degree detection model includes:

[0010] A training set is constructed based on the acquired performance data of the impulse current that the target arrester has been subjected to in the past and the corresponding environmental data;

[0011] The training set is input into a lightning arrester degradation degree detection model pre-constructed based on a neural network, and the trained lightning arrester degradation degree detection model is obtained through training.

[0012] Furthermore, the performance data of the impulse current includes amplitude and waveform, and the environmental data includes temperature and relative humidity.

[0013] Furthermore, based on the newly added degree of deterioration of the arrester caused by the most recent surge current and the number of times the arrester can withstand the maximum surge current, the number of times the arrester can withstand the maximum surge current is calculated, and the calculation is performed by the following formula:

[0014] ;

[0015] Among them, N out N is the number of times the arrester has consumed the maximum impulse current it can withstand under normal temperature and normal relative humidity. max N is the number of times the arrester can withstand the maximum impulse current under normal temperature and normal relative humidity. i is the number of times the arrester can withstand the i-th impulse current under normal temperature and relative humidity. The value of i is an integer from 1 to n. The n-th impulse current is the most recent impulse current. F(I i ) is the amplitude influence of the ith impulse current, F(W i ) is the waveform influence of the ith impulse current, F(T i ) is the temperature influence of the ith impulse current, F(RH i ) is the relative humidity influence of the ith impulse current;

[0016] in, , A i1 It is the additional degree of deterioration of the arrester caused by the i-th impulse current.

[0017] Furthermore, the normal temperature is 20° C., and the normal relative humidity is 60%.

[0018] Furthermore, the amplitude influence of the i-th impulse current is calculated by the following method:

[0019] If the amplitude of the i-th impulse current is closer to the first amplitude level, it is calculated using the following formula:

[0020] ;

[0021] ;

[0022] ;

[0023] Among them, F(I iu ) is the influence of the second amplitude level of the current, I i is the amplitude of the ith impulse current, I iu is the second amplitude gear, F(I id ) is the influence of the first amplitude level, I id is the first amplitude gear, N id is the number of times the arrester can withstand the impulse current corresponding to the first amplitude gear, N iu is the number of times the arrester can withstand the corresponding impulse current of the second amplitude gear, F(I iu ) and F(I id ) is obtained in advance through experiments;

[0024] If the amplitude of the i-th impulse current is closer to the second amplitude level, it is calculated using the following formula:

[0025] ;

[0026] The first amplitude level is smaller than the second amplitude level.

[0027] Furthermore, the waveform influence of the i-th impulse current is calculated by the following method:

[0028] If the waveform of the i-th impulse current is closer to the first waveform level, it is calculated using the following formula:

[0029] ;

[0030] ;

[0031] ;

[0032] Among them, W i is the waveform of the ith impulse current, F(W id ) is the influence of the first waveform position, W id It is the first waveform gear, F(W iu ) is the influence of the second waveform gear, F(W i-1 ) is the waveform influence of the i-1th impulse current, W iu It is the second waveform gear, W max It is the maximum waveform of the impulse current and the voltage that the arrester can withstand. max The number of impulse currents corresponding to the arrester is W id The number of corresponding surge currents;

[0033] If the waveform of the i-th impulse current is closer to the second waveform level, it is calculated using the following formula:

[0034] ;

[0035] The first waveform gear is smaller than the second waveform gear.

[0036] Furthermore, the temperature influence of the i-th impulse current is calculated by the following method:

[0037] If the temperature during the i-th impulse current shock is closer to the first temperature level, it is calculated using the following formula:

[0038] ;

[0039] ;

[0040] ;

[0041] Among them, T i is the temperature at the time of the ith impulse current shock, F(T id ) is the influence of the first temperature level, T id is the first temperature level, F(T iu ) is the influence of the second temperature level, T iu is the second temperature level, T max It is the highest temperature when the impulse current strikes, and it is the maximum temperature of the arrester at T max The number of times the arrester can withstand the i-th impulse current at T id The number of times it can withstand the i-th impulse current;

[0042] If the temperature during the i-th impulse current shock is closer to the second temperature level, it is calculated using the following formula:

[0043] ;

[0044] The first temperature level is lower than the second temperature level.

[0045] Furthermore, the relative humidity influence of the i-th impulse current is calculated by the following method:

[0046] If the relative humidity during the i-th impulse current shock is closer to the first relative humidity level, it is calculated using the following formula:

[0047] ;

[0048] ;

[0049] ;

[0050] Among them, RH i is the relative humidity at the time of the ith impulse current shock, F(RH id ) is the influence of the first relative humidity level, RH id It is the first relative humidity level, F(RH iu ) is the influence of the second relative humidity level, RH iu The second relative humidity level, RH max It is the highest relative humidity when the impulse current strikes, and it is the relative humidity of the arrester at RH max The number of times the arrester can withstand the i-th impulse current is id The number of times it can withstand the i-th impulse current;

[0051] If the relative humidity during the i-th impulse current shock is closer to the second relative humidity level, it is calculated using the following formula:

[0052] ;

[0053] The first relative humidity level is lower than the second relative humidity level.

[0054] In a second aspect, the present invention provides a lightning arrester degradation degree detection system, comprising:

[0055] The impulse data acquisition module is configured to: acquire performance data of the most recent impulse current borne by the arrester, environmental data when the arrester borne the most recent impulse current, and the number of times the arrester can withstand the maximum impulse current;

[0056] The first detection module is configured to: input the performance data and the environmental data into a trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current;

[0057] The second detection module is configured to: calculate the number of times the arrester can withstand the maximum impulse current based on the newly added deterioration degree of the arrester subjected to the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the degree of deterioration of the arrester;

[0058] The arrester degradation degree detection model is trained based on the performance data of the surge current that the arrester has been subjected to in the past and the corresponding environmental data.

[0059] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0060] The present invention provides a method and system for detecting the degree of degradation of a lightning arrester. A model is trained using the impulse current data that the lightning arrester has been subjected to in the past. The model is used to obtain the newly added degree of degradation of the lightning arrester when it is subjected to the most recent impulse current. On this basis, the current degree of degradation of the lightning arrester is calculated. The current degree of degradation can accurately reflect whether the lightning arrester can still withstand the maximum impulse current, that is, it can accurately indicate whether the lightning arrester needs to be replaced, thereby improving the accuracy of the detection of the degree of degradation of the lightning arrester and reducing the possibility of greater circuit risks caused by damage to the lightning arrester. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 is a flow chart of a method for detecting the degradation degree of a lightning arrester provided by an embodiment of the present invention;

[0062] Figure 2 It is a data schematic diagram for evaluating the influence of various indicators of impulse current on the arrester provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the protection scope of the present invention.

[0064] Embodiment 1, as Figure 1 As shown, the present invention provides a method for detecting the degradation degree of a lightning arrester, comprising:

[0065] Obtain the performance data of the most recent surge current that the arrester has been subjected to, the environmental data when it was subjected to the most recent surge current, and the number of times the arrester can withstand the maximum surge current;

[0066] Input the performance data and environmental data into the trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current.

[0067] Based on the newly added deterioration degree of the arrester caused by the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, calculate the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the deterioration degree of the arrester;

[0068] The training of the arrester degradation detection model includes:

[0069] A training set is constructed based on the acquired performance data of the impulse current that the target arrester has been subjected to in the past and the corresponding environmental data;

[0070] The training set is input into a lightning arrester degradation degree detection model pre-built based on a neural network, and a trained lightning arrester degradation degree detection model is obtained through training.

[0071] The present invention uses the impulse current data that the lightning arrester has been subjected to in the past to train a model, and uses the model to obtain the newly added degree of degradation of the lightning arrester when it is subjected to the most recent impulse current. On this basis, the current degree of degradation of the lightning arrester is calculated. The current degree of degradation can accurately reflect whether the lightning arrester can still withstand the maximum impulse current, that is, it can accurately indicate whether the lightning arrester needs to be replaced, thereby improving the accuracy of the detection of the degree of degradation of the lightning arrester and reducing the possibility of greater circuit risks caused by damage to the lightning arrester.

[0072] Embodiment 2, compared with the prior art, a more scientific way to judge the deterioration degree of the arrester is to measure whether the arrester still has the ability to protect the power supply line and the facilities on the line, or whether the arrester can still withstand the specified impulse current. If it cannot withstand the specified impulse current, the arrester should be replaced immediately. In this way, a detection method for calculating the deterioration degree of the arrester using the impulse current is needed to solve this problem.

[0073] The main factors that cause the arrester to deteriorate due to the impulse current are the amplitude of the impulse current, the waveform of the impulse current, the temperature and relative humidity when the impulse current occurs, the interval time of the impulse current, etc. These factors are the main reasons for accelerating the arrester. The present invention defines the lightning waveform with a waveform of 8 / 20μS, a temperature of 20°C, and a relative humidity of 60% as a normal environment (each data is the corresponding normal waveform, normal temperature, and normal relative humidity), and the impact under the normal environment is a normal impact. Each impact is converted into the number of times under the maximum impulse current. For example, under normal conditions, the arrester can withstand 125kA impulse current 42 times, or withstand 25kA impulse current 1275 times, then each 25kA impulse current is equivalent to 42 / 1275≈0.033 times 125kA impact. According to the above description, the present invention makes the following definition: the degree of deterioration added by the arrester each time it withstands an impulse current is the number of times the arrester can withstand the maximum impulse current divided by the square of the number of times the arrester can withstand the impulse current.

[0074] If we do not consider the influence of abnormal factors such as the arrester being damaged by external forces, the aging and leakage of the seal due to wind and sun, and the strong current shock exceeding the capacity, the remaining shock-bearing capacity of the arrester can be expressed by Formula 1:

[0075] (1);

[0076] Among them, N r N is the number of times the arrester can withstand the maximum impulse current at normal temperature and relative humidity. max N is the number of times the arrester can withstand the maximum impulse current under normal temperature and normal relative humidity. iis the number of times the arrester can withstand the i-th impulse current under normal temperature and relative humidity. The value of i is an integer from 1 to n. The n-th impulse current is the most recent impulse current. F(I i ) is the amplitude influence of the ith impulse current, F(W i ) is the waveform influence of the ith impulse current, F(T i ) is the temperature influence of the ith impulse current, F(RH i ) is the relative humidity influence of the ith impulse current;

[0077] in, , A i1 It is the additional degree of deterioration of the arrester caused by the nth impulse current.

[0078] Before the detection, a lightning arrester degradation degree detection model is established and trained based on the amplitude, waveform, temperature and relative humidity of the impulse current previously borne by the lightning arrester (except the most recent one). The above data are measured by the lightning arrester monitoring device and the corresponding sensors.

[0079] Evaluate the impact of various indicators of impulse current on the number of impulse currents that the arrester can withstand: The standard for judging the quality of the arrester is that the arrester cannot provide protection during the next test. For example, under certain test conditions (same amplitude, waveform, temperature, humidity, etc.), if the arrester is open-circuited, cracked, exploded, etc., and x tests are conducted, then the arrester's ability to withstand impulses under these conditions is x-1 impulses under these test conditions. The data used for this evaluation are as follows: Figure 2 shown.

[0080] Figure 2 In the figure, the horizontal axis is the amplitude of the impulse current, the unit is A, the vertical axis is the relative humidity when the impulse current strikes, the unit is %, and the vertical axis is the temperature when the impulse current strikes, the unit is ℃; the amplitude has five gears of 25kA, 50kA, 75kA, 100kA and 125kA, the waveform has four gears of 4 / 10μS impulse wave, 8 / 20μS shock wave, 10 / 350μS shock wave and 2000μS shock square wave, the relative humidity has four gears of 40%, 60%, 80% and 90%, and the temperature has five gears of -40℃, -20℃, 0℃, 20℃ and 40℃.

[0081] The impact of amplitude is evaluated as follows: take a lightning arrester as a sample, the waveform of the impulse current is 8 / 20μS, and conduct an impact evaluation test of the impulse current amplitude, and test the impact of different amplitudes on the life of the lightning arrester. The amplitude of the impulse current is a key indicator that determines the life of the lightning arrester. When the amplitude of the impulse current exceeds the maximum value allowed by the lightning arrester, it will cause irreversible damage to the lightning arrester, and the lightning arrester is close to or has failed. Therefore, as long as the lightning arrester is subjected to an impulse current amplitude that exceeds the maximum allowable value, it is judged that the lightning arrester has been scrapped and should be replaced immediately. When evaluating, the waveform selects the closest waveform, the temperature selects the closest temperature, and the humidity selects the closest humidity.

[0082] If the impulse current amplitude is within the arrester's tolerance range, the amplitude influence of the ith impulse current is calculated by the following method:

[0083] If the amplitude of the i-th impulse current is closer to the first amplitude level, it is calculated using the following formula:

[0084] (2-1);

[0085] (2-1-1);

[0086] (2-1-2);

[0087] Among them, F(I iu ) is the influence of the second amplitude level of the current, I i is the amplitude of the ith impulse current, I iu is the second amplitude gear, F(I id ) is the influence of the first amplitude level, I id is the first amplitude gear, N id is the number of times the arrester can withstand the impulse current corresponding to the first amplitude gear, N iu is the number of times the arrester can withstand the corresponding impulse current of the second amplitude gear, F(I iu ) and F(I id ) is obtained in advance through experiments.

[0088] If the amplitude of the i-th impulse current is closer to the second amplitude level, it is calculated using the following formula:

[0089] (2-2);

[0090] The first amplitude gear is smaller than the second amplitude gear, and the two gears are adjacent.

[0091] The impact of the waveform is evaluated as follows: take a lightning arrester as a sample, and perform impulse current tests on the lightning arrester with 4 / 10μS, 8 / 20μS, 10 / 350μS and 2000μS square waves respectively, and evaluate the impact of the impulse current under different impulse waveforms on the life of the lightning arrester.

[0092] Then the waveform influence of the i-th impulse current is calculated by the following method:

[0093] If the waveform of the i-th impulse current is closer to the first waveform level, it is calculated using the following formula:

[0094] (3-1);

[0095] (3-1-1);

[0096] (3-1-2);

[0097] Among them, W i is the waveform of the ith impulse current, F(W id ) is the influence of the first waveform position, W id It is the first waveform gear, F(W iu ) is the influence of the second waveform gear, F(W i-1 ) is the waveform influence of the i-1th impulse current, W iu It is the second waveform gear, W max It is the maximum waveform of the impulse current and the voltage that the arrester can withstand. max The number of impulse currents corresponding to the arrester is W id The number of corresponding surge currents.

[0098] If the waveform of the i-th impulse current is closer to the second waveform level, it is calculated using the following formula:

[0099] (3-2);

[0100] The first waveform gear is smaller than the second waveform gear, and the first waveform gear is adjacent to the second waveform gear.

[0101] The impact of temperature is evaluated as follows: take a lightning arrester as a sample, and conduct impulse current tests on the lightning arrester at different temperatures of -40℃, -20℃, 0℃, 20℃, and 40℃, and evaluate the impact of impulse current at different temperatures on the life of the lightning arrester.

[0102] The temperature influence of the i-th impulse current is calculated by the following method:

[0103] If the temperature during the i-th impulse current shock is closer to the first temperature level, it is calculated using the following formula:

[0104] (4-1);

[0105] (4-1-1);

[0106] (4-1-2);

[0107] Among them, T i is the temperature at the time of the ith impulse current shock, F(T id ) is the influence of the first temperature level, T id is the first temperature level, F(T iu ) is the influence of the second temperature level, T iu is the second temperature level, T max It is the highest temperature when the impulse current strikes, and it is the maximum temperature of the arrester at T max The number of times the arrester can withstand the i-th impulse current at T id The number of times it can withstand the i-th impulse current.

[0108] If the temperature during the i-th impulse current shock is closer to the second temperature level, it is calculated using the following formula:

[0109] (4-2);

[0110] The first temperature level is smaller than the second temperature level, and the two levels are adjacent to each other.

[0111] The impact of relative humidity is evaluated as follows: take a lightning arrester as a sample, test the lightning arrester at 40%, 60%, 80% and 90% relative humidity, and evaluate the impact of the impulse current under different relative humidity on the life of the lightning arrester.

[0112] The relative humidity influence of the i-th impulse current is calculated by the following method:

[0113] If the relative humidity during the i-th impulse current shock is closer to the first relative humidity level, it is calculated using the following formula:

[0114] (5-1);

[0115] (5-1-1);

[0116] (5-1-2);

[0117] Among them, RH iis the relative humidity at the time of the ith impulse current shock, F(RH id ) is the influence of the first relative humidity level, RH id It is the first relative humidity level, F(RH iu ) is the influence of the second relative humidity level, RH iu The second relative humidity level, RH max It is the highest relative humidity when the impulse current strikes, and it is the relative humidity of the arrester at RH max The number of times the arrester can withstand the i-th impulse current is id The number of times it can withstand the i-th impulse current.

[0118] If the relative humidity during the i-th impulse current shock is closer to the second relative humidity level, it is calculated using the following formula:

[0119] (5-2);

[0120] The first relative humidity level is lower than the second relative humidity level, and the two levels are adjacent.

[0121] The steps for detecting the degradation degree of a lightning arrester can be summarized as follows:

[0122] S1. Obtain the performance data of the most recent surge current withstood by the arrester, the environmental data when withstood the most recent surge current, and the number of times the arrester can withstand the maximum surge current.

[0123] S2. Input the performance data and environmental data into the trained arrester degradation degree detection model described above to obtain the additional degradation degree of the arrester caused by the most recent impulse current.

[0124] The training of the arrester degradation detection model includes:

[0125] A training set is constructed based on the acquired performance data of the impulse current that the target arrester has been subjected to in the past and the corresponding environmental data;

[0126] The training set is input into a lightning arrester degradation degree detection model pre-built based on a neural network, and a trained lightning arrester degradation degree detection model is obtained through training.

[0127] The above neural network may adopt convolutional neural network, artificial neural network, recurrent neural network, etc. In this embodiment, a convolutional neural network is adopted.

[0128] S3. Based on the newly added degree of deterioration of the arrester caused by the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, calculate the number of times the arrester has consumed the maximum impulse current (specifically implemented by the above formula 2-1, formula 2-1-1, formula 2-1-2, formula 2-2, formula 3-1, formula 3-1-1, formula 3-1-2, formula 3-2, formula 4-1, formula 4-1-1, formula 4-1-2, formula 4-2, formula 5-1, formula 5-1-1, formula 5-1-2, formula 5-2 and formula 6 below), and divide the number of times the arrester has consumed the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the degree of deterioration of the arrester;

[0129] (6);

[0130] Among them, N out N is the number of times the arrester has consumed the maximum impulse current it can withstand under normal temperature and normal relative humidity. max N is the number of times the arrester can withstand the maximum impulse current under normal temperature and normal relative humidity. i is the number of times the arrester can withstand the i-th impulse current under normal temperature and relative humidity. The value of i is an integer from 1 to n. The n-th impulse current is the most recent impulse current. F(I i ) is the amplitude influence of the ith impulse current, F(W i ) is the waveform influence of the ith impulse current, F(T i ) is the temperature influence of the ith impulse current, F(RH i ) is the relative humidity influence of the ith impulse current;

[0131] in, , A i1 It is the additional degree of deterioration of the arrester caused by the nth impulse current.

[0132] The following is a calculation of a specific example:

[0133] The 35kV arrester can withstand a maximum of 125kA impulse current 40 times, or 100kA impulse current 81 times. When the arrester has been subjected to 100kA impulse current 79 times, it can no longer withstand 125kA impulse current. In this case, the arrester should be considered a severely deteriorated product and should be replaced as soon as possible to avoid the arrester being subjected to large current shocks, explosions, and line power outages.

[0134] Since the arrester degradation degree increases gradually as the waveform becomes wider, F(W i) is the waveform influence of the ith impulse current, which is a value greater than 1. However, in actual calculation, the waveform is difficult to represent numerically. The following waveform influence is calculated by directly selecting the corresponding data from the model coordinates based on a certain model, where: Waveform 1 represents 4 / 10μS; Waveform 2 represents 8 / 20μS; Waveform 3 represents 10 / 350μS; Waveform 4 represents 2000μS square wave.

[0135] As shown in Table 1, the first impulse current was 27kA, the impulse waveform was 8 / 20μS, the temperature was 3°C, and the relative humidity was 57%. According to the degradation assessment model diagram, the first amplitude gear was 25kA, the second amplitude gear was 50kA, the impulse waveform was 8 / 20μS, the temperature was close to 0°C, the relative humidity was close to 60%, and the impulse current was close to 25kA.

[0136] Table 1- Calculation statistics of surge current degradation of lightning arrester

[0137] The equivalent maximum number of impacts is defined as the number of times the maximum impact current can be tolerated.

[0138] The calculation process is given for some of the data in Table 1:

[0139] (1) Calculation of amplitude influence:

[0140] I max =125kA (20℃, 60%, 8 / 20μS), N Imax =42;

[0141] I id =25kA (20℃, 60%, 8 / 20μS), N id =1195;

[0142] I iu =50kA (20℃, 60%, 8 / 20μS), N iu =596;

[0143] Since 27kA is close to 25kA, it should be slightly larger than the data of 25kA. Use formula 2-2 to calculate F(I1), F(I1)=1.00021.

[0144] (2) Calculation of temperature influence:

[0145] T max =80 (to make the multiplication and division data not equal to 0, the temperature is shifted by 40, and the temperature -40℃ is regarded as 0), N Tmax =1134;

[0146] T id =40,N Tid=1174;

[0147] T iu =60,N Tiu =1156;

[0148] The temperature is relatively close to 0℃, so use the data above 0℃ and calculate using Formula 4-1, F(T1)=1.0716.

[0149] (3) Calculation of relative humidity influence:

[0150] RH max =90%, N RHmax =924;

[0151] RH id =40%, N RHid =1294;

[0152] RH iu =60%, N RHiu =1174;

[0153] F(RH i )=1.3068;

[0154] The relative humidity is close to 60%, so use the data below 60% and calculate using Formula 5-2.

[0155] (4) Equivalent maximum number of impacts:

[0156] Equivalent maximum number of impacts = N id / Nmax×(F(I1)×F(W1)×F(T1)×F(RH1)=0.073;

[0157] After the first impulse current shock, the degree of degradation of the lightning arrester is 0.073 / 40=0.1825%.

[0158] By calculating each impulse current converted into the maximum impulse current value, summing up the converted values, we can get the number of times all impulse currents are equivalent to the maximum impulse current, and then subtract the converted number of impulses from the maximum impulse current's allowed number of impulses to see if it is greater than 1. From the above calculation, it is far greater than 1, which means that the arrester is still at a low level of degradation.

[0159] Embodiment 3, the present invention provides a lightning arrester degradation degree detection system, comprising:

[0160] The impulse data acquisition module is configured to: acquire performance data of the most recent impulse current borne by the arrester, environmental data when the arrester borne the most recent impulse current, and the number of times the arrester can withstand the maximum impulse current;

[0161] The first detection module is configured to: input the performance data and the environmental data into a trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current;

[0162] The second detection module is configured to: calculate the number of times the arrester can withstand the maximum impulse current based on the newly added deterioration degree of the arrester subjected to the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the degree of deterioration of the arrester;

[0163] The training of the arrester degradation detection model includes:

[0164] A training set is constructed based on the acquired performance data of the impulse current that the target arrester has been subjected to in the past and the corresponding environmental data;

[0165] The training set is input into a lightning arrester degradation degree detection model pre-built based on a neural network, and a trained lightning arrester degradation degree detection model is obtained through training.

[0166] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0167] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0168] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0169] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0170] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for detecting the degradation degree of a lightning arrester, characterized in that: include: Obtain the performance data of the most recent surge current that the arrester has been subjected to, the environmental data when it was subjected to the most recent surge current, and the number of times the arrester can withstand the maximum surge current; Inputting the performance data and the environmental data into a trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current; Based on the newly added deterioration degree of the arrester caused by the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, calculate the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the deterioration degree of the arrester; The training of the arrester degradation degree detection model includes: A training set is constructed based on the acquired performance data of the impulse current that the target arrester has been subjected to in the past and the corresponding environmental data; Inputting the training set into a lightning arrester degradation degree detection model pre-constructed based on a neural network, and training to obtain the trained lightning arrester degradation degree detection model; The number of times the arrester can withstand the maximum impulse current is calculated based on the newly added degree of deterioration caused by the arrester withstanding the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, and is calculated using the following formula: ； Among them, N out N is the number of times the arrester has consumed the maximum impulse current it can withstand under normal temperature and normal relative humidity. max N is the number of times the arrester can withstand the maximum impulse current under normal temperature and normal relative humidity. i is the number of times the arrester can withstand the i-th impulse current under normal temperature and relative humidity. The value of i is an integer from 1 to n. The n-th impulse current is the most recent impulse current. F(I i ) is the amplitude influence of the ith impulse current, F(W i ) is the waveform influence of the ith impulse current, F(T i ) is the temperature influence of the ith impulse current, F(RH i ) is the relative humidity influence of the ith impulse current; in, , A i1 It is the additional degree of deterioration of the arrester caused by the i-th impulse current.

2. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The performance data of the impulse current includes amplitude and waveform, and the environmental data includes temperature and relative humidity.

3. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The normal temperature is 20° C., and the normal relative humidity is 60%.

4. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The amplitude influence of the i-th impulse current is calculated by the following method: If the amplitude of the i-th impulse current is closer to the first amplitude level, it is calculated using the following formula: ； ； ； Among them, F(I iu ) is the influence of the second amplitude level of the current, I i is the amplitude of the ith impulse current, I iu is the second amplitude gear, F(I id ) is the influence of the first amplitude level, I id is the first amplitude gear, N id is the number of times the arrester can withstand the impulse current corresponding to the first amplitude gear, N iu is the number of times the arrester can withstand the impulse current corresponding to the second amplitude level, F(I iu ) and F(I id ) is obtained in advance through experiments; If the amplitude of the i-th impulse current is closer to the second amplitude level, it is calculated using the following formula: ； The first amplitude level is smaller than the second amplitude level.

5. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The waveform influence of the i-th impulse current is calculated by the following method: If the waveform of the i-th impulse current is closer to the first waveform level, it is calculated using the following formula: ； ； ； Among them, W i is the waveform of the ith impulse current, F(W id ) is the influence of the first waveform position, W id It is the first waveform gear, F(W iu ) is the influence of the second waveform gear, F(W i-1 ) is the waveform influence of the i-1th impulse current, W iu It is the second waveform gear, W max It is the maximum waveform of the impulse current and the voltage that the arrester can withstand. max The number of impulse currents corresponding to the arrester is W id The number of corresponding impact currents; If the waveform of the i-th impulse current is closer to the second waveform level, it is calculated using the following formula: ； The first waveform gear is smaller than the second waveform gear.

6. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The temperature influence of the i-th impulse current is calculated by the following method: If the temperature during the i-th impulse current shock is closer to the first temperature level, it is calculated using the following formula: ； ； ； Among them, T i is the temperature at the time of the ith impulse current shock, F(T id ) is the influence of the first temperature level, T id is the first temperature level, F(T iu ) is the influence of the second temperature level, T iu is the second temperature level, T max It is the highest temperature when the impulse current strikes, and it is the maximum temperature of the arrester at T max The number of times the arrester can withstand the i-th impulse current at T id The number of times it can withstand the i-th impulse current; If the temperature during the i-th impulse current shock is closer to the second temperature level, it is calculated using the following formula: ； The first temperature level is lower than the second temperature level.

7. The method for detecting the degradation degree of a lightning arrester according to claim 1, characterized in that: The relative humidity influence of the i-th impulse current is calculated by the following method: If the relative humidity during the i-th impulse current shock is closer to the first relative humidity level, it is calculated using the following formula: ； ； ； Among them, RH i is the relative humidity at the time of the ith impulse current shock, F(RH id ) is the influence of the first relative humidity level, RH id It is the first relative humidity level, F(RH iu ) is the influence of the second relative humidity level, RH iu The second relative humidity level, RH max It is the highest relative humidity when the impulse current strikes, and it is the relative humidity of the arrester at RH max The number of times the arrester can withstand the i-th impulse current is id The number of times it can withstand the i-th impulse current; If the relative humidity during the i-th impulse current shock is closer to the second relative humidity level, it is calculated using the following formula: ； The first relative humidity level is lower than the second relative humidity level.

8. A lightning arrester degradation degree detection system, characterized in that: include: The impulse data acquisition module is configured to: acquire performance data of the most recent impulse current borne by the arrester, environmental data when the arrester borne the most recent impulse current, and the number of times the arrester can withstand the maximum impulse current; The first detection module is configured to: input the performance data and the environmental data into a trained arrester degradation degree detection model to obtain the additional degradation degree of the arrester caused by the most recent impulse current; The second detection module is configured to: calculate the number of times the arrester can withstand the maximum impulse current based on the newly added deterioration degree of the arrester subjected to the most recent impulse current and the number of times the arrester can withstand the maximum impulse current, and divide the number of times the arrester can withstand the maximum impulse current by the number of times the arrester can withstand the maximum impulse current to obtain the degree of deterioration of the arrester; The arrester degradation degree detection model is trained based on the performance data of the surge current that the arrester has been subjected to in the past and the corresponding environmental data; In the second detection module, the number of times the arrester can withstand the maximum impact current is calculated based on the newly added degree of deterioration caused by the arrester withstanding the most recent impact current and the number of times the arrester can withstand the maximum impact current, and the calculation is performed by the following formula: ； Among them, N out N is the number of times the arrester has consumed the maximum impulse current it can withstand under normal temperature and normal relative humidity. max N is the number of times the arrester can withstand the maximum impulse current under normal temperature and normal relative humidity. i is the number of times the arrester can withstand the i-th impulse current under normal temperature and relative humidity. The value of i is an integer from 1 to n. The n-th impulse current is the most recent impulse current. F(I i ) is the amplitude influence of the ith impulse current, F(W i ) is the waveform influence of the ith impulse current, F(T i ) is the temperature influence of the ith impulse current, F(RH i ) is the relative humidity influence of the ith impulse current; in, , A i1 It is the additional degree of deterioration of the arrester caused by the i-th impulse current.

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