Intelligent ultrahigh voltage series resonance withstand voltage test method and test platform

Abstract

This application relates to an intelligent ultra-high voltage series resonant withstand voltage test method and test platform. The method includes: analyzing the amplitude deviation between the current frequency point and its neighboring frequency points during frequency sweeping to obtain the amplitude mutation rate of the current frequency point; if the amplitude mutation rate of the current frequency point is not less than a trigger threshold and the amplitude mutation rate of the current frequency point is less than the amplitude mutation rate of neighboring frequency points, determining the backoff distance and target step size based on the current sweep step size and reference bandwidth, backing off from the current frequency point by the backoff distance, and continuing the frequency sweep with the target step size; determining multiple candidate peaks based on the extreme points in the local curvature of multiple frequency points; performing fine sweeping on at least some of the candidate peaks to obtain the resonant frequency of each finely swept candidate peak, and determining the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency, which is the resonant frequency for the withstand voltage test. This application can improve the safety of withstand voltage tests on ultra-high voltage equipment.

Description

Technical Field

[0001] This application relates to the field of electrical variable measurement technology, and in particular to an intelligent ultra-high voltage series resonant withstand voltage test method and test platform. Background Technology

[0002] Current UHV series resonant withstand voltage tests generally employ a two-stage approach to determine the resonant point: a fixed-step coarse frequency sweep followed by a single-target fine frequency sweep. In the coarse sweep stage, the system scans a wide range with a preset fixed frequency step size, monitoring the circuit current in real time and recording the frequency point with the largest current amplitude, which is then preliminarily determined as the resonant frequency. Subsequently, a second fine sweep is performed near this frequency point with a smaller step size to ultimately lock the resonant frequency. This method can quickly and effectively determine the resonant frequency when testing a single, ideal capacitive load (such as a single cable). However, when handling withstand voltage tests of UHV equipment (such as UHV transformers, GIS, generators, etc.), the fixed-step coarse sweep mode cannot effectively address the "multiple resonant peaks and narrow bandwidth" characteristics generated by the complex internal structure of UHV equipment. It is highly prone to missing key resonant peaks in the coarse sweep stage, resulting in the final locked resonant frequency not being the main resonant point of the equipment, thus affecting the effectiveness and safety of the test. Summary of the Invention

[0003] To address the aforementioned technical problems, the purpose of this application is to provide an intelligent ultra-high voltage series resonant withstand voltage test method and test platform, the specific technical solution of which is as follows: Firstly, an intelligent ultra-high voltage series resonant withstand voltage test method is provided, the method comprising: Frequency sweeping is performed on the ultra-high voltage equipment. During the frequency sweeping process, the amplitude deviation between the current frequency point and its neighboring frequency points is analyzed to obtain the amplitude mutation rate of the current frequency point. If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, the back-off distance and target step size are determined according to the current sweep step size and reference bandwidth, the back-off distance is reversed from the current frequency point, and the sweep frequency is continued with the target step size; After completing the frequency sweep of the UHV equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points. At least some of the candidate peaks among the multiple candidate peaks are finely scanned to obtain the resonant frequency of each finely scanned candidate peak, and the resonant frequency corresponding to the candidate peak with the largest current value is determined as the main resonant frequency, which is the resonant frequency for the withstand voltage test.

[0004] Optionally, before performing a frequency sweep on the UHV equipment and analyzing the amplitude deviation between the current frequency point and its neighboring frequency points during the frequency sweep to obtain the amplitude abrupt change rate at the current frequency point, the process further includes: The UHV equipment is pre-scanned using a preset pre-scanning step size to obtain pre-scanning data; Calculate the amplitude change rate of each pair of adjacent frequency points based on the ratio of the current difference between each pair of adjacent frequency points in the pre-scan data to the pre-scan step size; Calculate the mean of the amplitude change rate of multiple pairs of adjacent frequency points to obtain the average amplitude change rate.

[0005] Optionally, frequency sweeping is performed on the UHV equipment. During the frequency sweeping process, the amplitude deviation between the current frequency point and its neighboring frequency points is analyzed to obtain the amplitude change rate at the current frequency point, including: The frequency of the UHV equipment is swept with a sweep step size. The current value at the current frequency point and the current value at its neighboring frequency points are collected. Based on the collected current time-domain waveform, the effective current value at the current frequency point and the effective current value at its neighboring frequency points are calculated to obtain the effective current value at the current frequency point and the effective current value at its neighboring frequency points. The sweep step size is a preset initial step size or a step size determined by the previous back-off operation. Calculate the absolute difference between the effective current values ​​of the current point and its neighboring frequency points to obtain the current difference value, and calculate the ratio of the current difference value to the sweep step size to obtain the amplitude change rate of the current frequency point; the neighboring frequency points of the current frequency point are its previous frequency points.

[0006] Optionally, if the amplitude mutation rate at the current frequency point is not less than the trigger threshold and the amplitude mutation rate at the current frequency point is less than the amplitude mutation rate at neighboring frequency points, or the amplitude mutation rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at a neighboring frequency point exceeds a preset current threshold, the backoff distance and target step size are determined based on the current sweep step size and reference bandwidth, including: If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or if the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, the reference bandwidth is determined based on the peak current value and the amplitude change rate at the current frequency point; the peak current value indicates the maximum current value among all frequency points from the start of the frequency sweep to the current frequency point. The backoff distance is determined based on the larger of half the current sweep step size and the reference bandwidth. The target step size is determined based on the smaller of one-third of the current sweep step size and one-quarter of the reference bandwidth.

[0007] Optionally, backtracking from the current frequency point by the backtracking distance and continuing frequency sweeping with a target step size includes: Move the current frequency point towards a lower frequency direction by the back-off distance, and use the reached frequency point as the back-off point; Starting from the backtracking point, continue performing the frequency sweep with the target step size.

[0008] Optionally, among the multiple frequency points obtained after frequency sweeping of the UHV equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points, including: After completing the frequency sweep of the UHV equipment, among the multiple frequency points obtained, for three frequency points continuously collected with the same phase length, the absolute difference between the sum of the current values ​​of the first frequency point and the third frequency point and twice the current value of the second frequency point is calculated to obtain the discrete second derivative of the second frequency point; where the second frequency point is the middle frequency point of the three frequency points, and the first and third frequency points are the frequency points before and after the second frequency point, respectively. The product of the square of the corresponding sweep step size and the discrete second derivative at the second frequency point is calculated to obtain the local curvature at the second frequency point; the local curvature is used to characterize the degree of bending of the curve of the current value changing with frequency at the second frequency point. When the local curvature of the second frequency point is greater than the dynamic curvature threshold, and the current value of the second frequency point is greater than the current values ​​of its two adjacent frequency points, the second frequency point is determined as a candidate peak; the dynamic curvature threshold is determined based on the average of the local curvatures of all frequency points before the second frequency point.

[0009] Optionally, after determining multiple candidate peaks based on the extreme points in the local curvature of the multiple frequency points obtained after frequency sweeping of the UHV equipment, the method further includes: Store multiple candidate peaks in a temporary peak list; Calculate the frequency difference between two adjacent candidate peaks in the temporary peak list. If the frequency difference is less than twice the minimum step size used in the current frequency sweep process, then the two adjacent candidate peaks are determined to be a suspected merged peak region. Within the suspected merged peak region, a second scan is performed with a preset scan step size, and the local curvature of each frequency point obtained by the scan is calculated. When the local curvature of a frequency point is greater than the dynamic curvature threshold, and the current value of the frequency point is simultaneously less than the current values ​​of its two adjacent frequency points, the frequency point is determined as the valley. If the frequency points on both sides of the valley meet the candidate peak conditions, then the maximum frequency points on both sides of the valley are stored as candidate peaks in the temporary peak list. Sort all candidate peaks in the temporary peak list in descending order of current value.

[0010] Optionally, a fine scan is performed on at least some of the candidate peaks to obtain the resonant frequency of each finely scanned candidate peak, including: For each candidate peak in the sorted temporary peak list, the current value of each frequency point is collected sequentially within the fine scan range corresponding to each candidate peak with a preset fixed step size; the fine scan range corresponding to each candidate peak is: with the frequency value corresponding to each candidate peak as the center, extending to both sides of a preset frequency range; For each candidate peak, the frequency points and their corresponding current values ​​collected within the fine scan range are fitted using a Lorentz curve, and the peak frequency of the fitted curve is taken as the resonant frequency of each candidate peak.

[0011] Optionally, the resonant frequency corresponding to the candidate peak with the largest current value is determined as the main resonant frequency, including: Select the candidate peak with the largest current value from all candidate peaks, and take the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency.

[0012] Secondly, an intelligent ultra-high voltage series resonant withstand voltage test platform is provided, the platform comprising: The frequency sweep module is used to sweep the frequency of UHV equipment. During the frequency sweep process, it analyzes the amplitude deviation between the current frequency point and its neighboring frequency points to obtain the amplitude change rate of the current frequency point. The first determining module is used to determine the back-off distance and target step size based on the current frequency sweep step size and reference bandwidth if the amplitude change rate of the current frequency point is not less than the trigger threshold and the amplitude change rate of the current frequency point is less than the amplitude change rate of the adjacent frequency point, or the amplitude change rate of the current frequency point is less than the trigger threshold and the current value of the current frequency point or the current value of the adjacent frequency point exceeds a preset current threshold. The module then backs off the current frequency point by the back-off distance and continues to sweep the frequency with the target step size. The second determining module is used to determine multiple candidate peaks based on the extreme points in the local curvature of multiple frequency points among multiple frequency points obtained after frequency sweeping of the UHV equipment. The test module is used to perform fine scanning on at least some of the candidate peaks among multiple candidate peaks to obtain the resonant frequency of each candidate peak after fine scanning, and to determine the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency, which is the resonant frequency for conducting the withstand voltage test.

[0013] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of this application.

[0014] This application has the following beneficial effects: During the frequency sweep process, the amplitude deviation between the current frequency point and its neighboring frequency points is analyzed in real time to obtain the amplitude mutation rate of the current frequency point. When the amplitude mutation rate of the current frequency point is not less than the trigger threshold and the amplitude mutation rate of the current frequency point is less than the amplitude mutation rate of the neighboring frequency points, the back-off distance and target step size are determined according to the current frequency sweep step size and reference bandwidth. The back-off distance is reversed from the current frequency point and the frequency sweep continues with the target step size, thereby realizing the back-off encrypted scanning of narrowband resonant peaks that may be crossed, effectively avoiding the problem of narrowband resonant peaks being missed due to fixed step size frequency sweep in the prior art. After frequency sweeping, multiple candidate peaks are determined based on the extreme points of local curvature at multiple frequency points. At least some of the candidate peaks are then finely swept to obtain the resonant frequency of each finely swept candidate peak. The resonant frequency corresponding to the candidate peak with the largest current value is determined as the main resonant frequency. By combining the identification of extreme points of local curvature with fine sweeping fitting, the accuracy of resonant frequency locking is significantly improved. Finally, a withstand voltage test is conducted at this main resonant frequency to ensure that the series resonant circuit is in the optimal resonant state, avoiding voltage output instability, waveform distortion, and the risk of overvoltage or undervoltage caused by improper selection of resonant points. This effectively improves the safety and effectiveness of withstand voltage tests on ultra-high voltage equipment. Attached Figure Description

[0015] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart of an intelligent ultra-high voltage series resonant withstand voltage test method in one embodiment; Figure 2 This is a schematic diagram of the structure of an intelligent ultra-high voltage series resonant withstand voltage test platform in one embodiment; Figure 3 This is a schematic diagram of the structure of an electronic device in one embodiment. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of an intelligent ultra-high voltage series resonant withstand voltage test method and test platform proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] The specific scheme of the intelligent ultra-high voltage series resonant withstand voltage test method provided in this application is described below with reference to the accompanying drawings. Figure 1 As shown, the method includes: S11. Perform frequency sweeping on the UHV equipment. During the frequency sweeping process, analyze the amplitude deviation between the current frequency point and its neighboring frequency points to obtain the amplitude mutation rate of the current frequency point.

[0020] In one embodiment, before performing a frequency sweep on the ultra-high voltage equipment and analyzing the amplitude deviation between the current frequency point and its neighboring frequency points during the frequency sweep process to obtain the amplitude abrupt change rate of the current frequency point, the method further includes: The UHV equipment is pre-scanned using a preset pre-scanning step size to obtain pre-scanning data; Calculate the amplitude change rate of each pair of adjacent frequency points based on the ratio of the current difference between each pair of adjacent frequency points in the pre-scan data to the pre-scan step size; Calculate the mean of the amplitude change rate of multiple pairs of adjacent frequency points to obtain the average amplitude change rate.

[0021] A voltage sensor and a current sensor are connected in parallel and in series at the output of the test platform. First, a rapid pre-scan frequency measurement is performed on the UHV equipment, starting at 20Hz and ending at 300Hz, with a preset pre-scan step size of 10Hz. At each preset frequency point, the system continuously samples for 0.1 seconds, acquiring the effective value of the loop current at that frequency, while simultaneously recording the ambient temperature and humidity, thus obtaining the pre-scan data. This pre-scan data is not the final result; its main purpose is to obtain the approximate current-frequency distribution profile of the UHV equipment under the current state, providing an initial reference for subsequent adaptive frequency scanning.

[0022] Using the collected pre-scan data, a baseline level for current variation across the entire frequency band is calculated. Specifically, based on the current difference between adjacent frequency points in the pre-scan data, the average amplitude change rate is calculated. The calculation formula is: ; in, The number of multiple frequency points in the pre-scan. For the first Each frequency point, For the first Current value at each frequency point For the first Current value at each frequency point The pre-scan step size is used to represent the average amplitude change rate, which reflects the average level of current change across the entire frequency band under a fixed large step size.

[0023] In one embodiment, frequency sweeping is performed on the ultra-high voltage equipment. During the frequency sweeping process, the amplitude deviation between the current frequency point and its neighboring frequency points is analyzed to obtain the amplitude change rate of the current frequency point, including: The frequency of the UHV equipment is swept with a sweep step size. The current value at the current frequency point and the current value at its neighboring frequency points are collected. Based on the collected current time-domain waveform, the effective current value at the current frequency point and the effective current value at its neighboring frequency points are calculated to obtain the effective current value at the current frequency point and the effective current value at its neighboring frequency points. The sweep step size is a preset initial step size or a step size determined by the previous back-off operation. Calculate the absolute difference between the effective current values ​​of the current point and its neighboring frequency points to obtain the current difference value, and calculate the ratio of the current difference value to the sweep step size to obtain the amplitude change rate of the current frequency point; the neighboring frequency points of the current frequency point are its previous frequency points.

[0024] The frequency of the UHV equipment is swept using a sweep step size, at each frequency point. At this location, according to the current sampling duration Acquire the effective value of the current After data acquisition, the amplitude abrupt change rate between the current point and neighboring frequency points is calculated. The amplitude abrupt change rate is constructed based on the physical characteristics of the current amplitude changing with frequency near the resonance peak of a series resonant circuit: in the non-resonant region, the current amplitude changes slowly with frequency, and the amplitude difference between adjacent points is small; while at the edge of the resonance peak, the current amplitude changes drastically with frequency, and the amplitude difference between adjacent points increases significantly. Therefore, the formula for calculating the amplitude abrupt change rate R is: ; in, This represents the effective current value at the current frequency point. This represents the effective current value at neighboring frequencies of the current frequency. R represents the frequency sweep step size, reflecting the degree of change in current amplitude per unit frequency change. It is an effective indicator for quantifying the steepness of local curves.

[0025] S12. If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, determine the back-off distance and target step size based on the current sweep step size and reference bandwidth, back off from the current frequency point by the back-off distance, and continue sweeping the frequency with the target step size.

[0026] The trigger threshold can be set according to the actual situation. It can be a preset value or calculated according to the following formula: ,in, As the trigger threshold, The preset multiplier is, for example, 4. This represents the average rate of change of amplitude.

[0027] The preset current threshold is determined based on pre-scan data. Specifically, the average current value at all frequency points in the pre-scan data is calculated, and the average value is multiplied by a first coefficient to obtain the preset current threshold; or, the maximum current value in the pre-scan data is multiplied by a second coefficient to obtain the preset current threshold. The first and second coefficients can be pre-calibrated according to the actual equipment type and on-site operating conditions. For example, the first coefficient can be a value between 1.5 and 3.0, and the second coefficient can be a value between 0.6 and 0.9.

[0028] When the calculated amplitude mutation rate R is less than the trigger threshold When the system is in a non-resonant region, the current changes smoothly and the electromagnetic noise level is low. Therefore, a large step size is maintained to improve frequency sweep efficiency, while the shortest sampling time is used to meet basic sampling requirements. The frequency sweep step size is... 10 Sampling time It takes 0.1 seconds.

[0029] When R is not less than the trigger threshold At this point, it is determined that the current location has entered the edge region of the resonance peak. The narrow bandwidth characteristic of the resonance peak of ultra-high voltage equipment means that: the larger the amplitude abrupt change rate R, the "steeper" the resonance peak, the narrower its effective bandwidth, and the smaller the required sweep step size; at the same time, the electromagnetic energy in the resonance region is highly concentrated, and noise interference is enhanced, requiring a longer sampling time for mean filtering to suppress noise. Based on this, it is established that R is not less than the trigger threshold. Scan frequency step size The relationship is inversely proportional to R, and R is not less than the trigger threshold. Sampling time The direct proportionality with R, specifically: ; ; in, R is not less than the trigger threshold The sweep step size at that time R is not less than the trigger threshold Sampling duration at time R is the step size adjustment factor (taken as 0.9A), which physically maps the detected rate of change to the step size. The larger R is, the smaller the step size. R is the sampling duration adjustment coefficient (taken as 0.05s·Hz / A). Its physical meaning is to map the rate of change to the sampling duration. The larger R is, the longer the sampling duration, in order to suppress stronger electromagnetic noise. and The function represents the minimum or maximum value and is used to limit the range of parameters. A lower limit of 0.5Hz ensures hardware responsiveness. A 1-second limit is set to avoid excessively reducing efficiency. For extremely small values, such as .

[0030] During dynamic frequency scanning, when detected At that time, relying solely on subsequently reducing the step size may still pose risks: if If the frequency is relatively large, but the resonant peak bandwidth is extremely narrow (e.g., 1Hz), then the frequency point... and These points may be located on either side of the resonance peak, spanning the entire peak. In this case, although the calculated R exceeds the threshold, it can no longer reconstruct the true shape of the peak, and continuing will completely miss the peak. Furthermore, when using a large step size for frequency sweeping, if the two sampling points fall at symmetrical or nearly symmetrical positions on either side of an extremely narrow resonance peak, and The values ​​will be very close, and at this time the amplitude mutation rate R is also less than the trigger threshold, but the current value itself may be high, and there is also a risk of missed detection.

[0031] Therefore, in one embodiment, if the amplitude mutation rate at the current frequency point is not less than the trigger threshold and the amplitude mutation rate at the current frequency point is less than the amplitude mutation rate at neighboring frequency points, or the amplitude mutation rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at a neighboring frequency point exceeds a preset current threshold, the backoff distance and target step size are determined based on the current sweep step size and reference bandwidth, including: If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or if the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, the reference bandwidth is determined based on the peak current value and the amplitude change rate at the current frequency point; the peak current value indicates the maximum current value among all frequency points from the start of the frequency sweep to the current frequency point. The backoff distance is determined based on the larger of half the current sweep step size and the reference bandwidth. The target step size is determined based on the smaller of one-third of the current sweep step size and one-quarter of the reference bandwidth.

[0032] Specifically, regressing the regression distance from the current frequency point and continuing frequency sweeping with a target step size includes: Move the current frequency point towards a lower frequency direction by the back-off distance, and use the reached frequency point as the back-off point; Starting from the backtracking point, continue performing the frequency sweep with the target step size.

[0033] The narrow bandwidth characteristic of the resonant peak in ultra-high voltage (UHV) equipment directly determines the necessity of a back-off mechanism. Let the bandwidth of a certain resonant peak be W, and its half-bandwidth be... When the sweep frequency step size When the current amplitude is greater than W, the resonance peak can be completely crossed, manifesting as two adjacent frequency points located at the valleys on either side of the peak. In this case, although the difference in current amplitude between the two points may be small (or even zero), a resonance peak with a very high amplitude actually exists in this region. Furthermore, when the two sampling points fall symmetrically on either side of the peak, the current difference also approaches zero, and the amplitude abrupt change rate R is extremely small, failing to trigger the backoff condition based on the abrupt change rate. Therefore, it is necessary to add a judgment dimension based on the absolute value of the current. The risk of missed detection in this case is related to the bandwidth W and the sweep step size. The ratio is directly related. Define the span coefficient. The calculation formula is: .when At that time, there is a risk that the resonance peak may be completely crossed; when At that time, the resonance peak is almost inevitably crossed. The narrow bandwidth W of ultra-high voltage equipment is typically 1-3Hz, while the initial step size... Since the frequency is 10Hz, the γ value is between 3.3 and 10, and crossing this range carries an extremely high risk.

[0034] To address the aforementioned issues, a quantitative indicator is needed to distinguish between "entering the resonance region" and "having already crossed the resonance peak." Simply relying on... These two scenarios cannot be distinguished because both can produce R values ​​exceeding the threshold. The key lies in analyzing the trend of R changes. Simultaneously, an auxiliary judgment condition based on the absolute value of the current should be added.

[0035] If the difference between the amplitude abrupt change rate at the current frequency and that at neighboring frequencies is not less than 0, it indicates that the amplitude abrupt change rate at the current frequency is not less than that at neighboring frequencies, and the amplitude change in the current region is intensifying, with the system approaching the peak. If the difference between the amplitude abrupt change rate at the current frequency and that at neighboring frequencies is less than 0, it indicates that the amplitude abrupt change rate at the current frequency is less than that at neighboring frequencies, and the amplitude change is weakening, with the system moving away from the peak region. If the current value at the current frequency or the current value at a neighboring frequency exceeds a preset current threshold, and the amplitude abrupt change rate at the current frequency is less than the trigger threshold, it is also determined that the resonant peak may have been crossed, triggering the backoff mechanism.

[0036] Based on this, construct a dual-threshold triggering logic: Scenario 1 (Normal Entry): When If the amplitude mutation rate at the current frequency point is not less than the amplitude mutation rate at the neighboring frequency points, it is determined that the system is approaching the peak from the edge of the peak. At this time, there is no need to backtrack, and it is only necessary to reduce the step size according to the aforementioned rules.

[0037] Scenario 2 (Possible Crossing): When Furthermore, if the amplitude mutation rate at the current frequency point is less than that at the neighboring frequency points, it is determined that the system may have crossed the peak—that is, the current point is located at the falling edge of the peak, while the neighboring frequency points are located at the rising edge of the peak, but due to the excessive step size, the intermediate peaks are completely skipped. At this time, the backoff mechanism is triggered.

[0038] After triggering a backoff, the backoff distance needs to be determined. A backoff that is too short may result in the peak not being covered, while a backoff that is too long will reduce efficiency. The backoff distance should be related to the current sweep step size and the reference bandwidth.

[0039] According to the frequency domain sampling theorem, to fully reconstruct a resonant peak with bandwidth W, the sampling step size should be less than [a certain value]. Since W is unknown, it can be estimated using the current mutation rate R. The slope of the resonance peak edge (which can be understood as being approximately equal to the value of R) has an approximately inverse relationship with the bandwidth W: ,in This represents the peak current value, indicating the maximum current value across all frequency points from the start of the frequency sweep to the current frequency. Therefore, the reference bandwidth... The calculation formula is: ; in, The preset maximum reference bandwidth is pre-calibrated according to the type of UHV equipment, for example, a value between 3Hz and 5Hz can be used to limit the upper limit of the estimated bandwidth, avoiding falsely large bandwidth estimates due to R being too small in different scenarios. If the exact current is not yet known during the rollback, the current can be used temporarily. This gives us the initial value for the reference bandwidth.

[0040] Back distance The backoff distance should be at least half the current sweep step size to ensure that potential peak regions can be re-covered with smaller step sizes. Simultaneously, the backoff distance should be correlated with the reference bandwidth to cover the entire peak. Backoff Distance The calculation formula is: ; in, R is not less than the trigger threshold The sweep step size at that time This is the reference bandwidth.

[0041] Current frequency point Move back a distance towards lower frequencies, back to And reduce the step size to 1 / 3 of the current sweep step size (or reduce it to...). (Take the smaller value), and start scanning again from the backtracking point with the target step size. It's understandable that during frequency sweeping, the frequency is usually swept from low to high frequencies (e.g., from 20Hz to 300Hz). Therefore, the low-frequency direction refers to the direction in which the frequency value decreases.

[0042] Target step size after rollback This directly determines whether the peaks being crossed can be effectively captured. If Still greater than However, the risk of crossing the threshold again remains. Adjusting the step size requires considering both the reduction ratio of the original step size (to ensure gradualism) and the estimation of the unknown bandwidth (to ensure sufficiency), taking the minimum of both to ensure the finest scan resolution. Therefore, the target step size... It needs to be based on the reference bandwidth. Determine the target step size. The calculation formula is: ; in, Guaranteed This satisfies the frequency domain sampling theorem.

[0043] In summary, the rollback process is as follows: When a rollback is detected... If the amplitude abrupt change rate at the current frequency is less than that at neighboring frequencies, it is determined that the resonance peak may have been crossed. Record the current frequency. and the previous frequency Calculate the reference bandwidth Determine the backtrack distance Reset the current frequency point to the rollback point. Update the step size to the target step size. The sampling duration is dynamically adjusted according to the aforementioned R relationship. From the rollback point... Start a rescan and continuously monitor the R value during the scan. When R drops back to... If two consecutive frequency points remain stable, it is determined that the resonant peak region has been completely scanned, and the original step size is restored to continue. The original step size is 10Hz.

[0044] S13. After completing the frequency sweep of the UHV equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points.

[0045] After frequency sweeping of ultra-high voltage equipment, it is necessary to accurately identify the peak position of the resonant peak among the multiple frequency points obtained. The series resonant current-frequency curve exhibits a Lorentzian curve near the resonant point, with its first derivative being zero and its second derivative (curvature) reaching an extreme value at the peak. Based on this, the local curvature method is used to identify the extreme point.

[0046] In one embodiment, among multiple frequency points obtained after frequency sweeping of the ultra-high voltage equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points, including: After completing the frequency sweep of the UHV equipment, among the multiple frequency points obtained, for three frequency points continuously collected with the same phase length, the absolute difference between the sum of the current values ​​of the first frequency point and the third frequency point and twice the current value of the second frequency point is calculated to obtain the discrete second derivative of the second frequency point; where the second frequency point is the middle frequency point of the three frequency points, and the first and third frequency points are the frequency points before and after the second frequency point, respectively. The product of the square of the corresponding sweep step size and the discrete second derivative at the second frequency point is calculated to obtain the local curvature at the second frequency point; the local curvature is used to characterize the degree of bending of the curve of the current value changing with frequency at the second frequency point. When the local curvature of the second frequency point is greater than the dynamic curvature threshold, and the current value of the second frequency point is greater than the current values ​​of its two adjacent frequency points, the second frequency point is determined as a candidate peak; the dynamic curvature threshold is determined based on the average of the local curvatures of all frequency points before the second frequency point.

[0047] For three frequency points continuously sampled with the same time interval , , Second frequency point Local curvature The calculation formula is: ; in, The current value at the third frequency point. This is the current value at the second frequency point. The current value at the first frequency point. The actual sweep step size used to collect the first, second, and third frequency points.

[0048] When C exceeds the dynamic curvature threshold At that time, the judgment The extreme point is defined as follows: the average curvature of all frequency points before the second frequency point is multiplied by a preset multiple to obtain the dynamic curvature threshold. The preset multiple can be a value between 3 and 5. Further determination of the extreme value type: If... and ,but This is a candidate peak (resonance peak); if and ,but This represents the valley bottom (the valley value between multiple peaks). The peak information (frequency, current amplitude, curvature) of all identified candidate peaks is stored in a temporary peak list.

[0049] In one embodiment, after determining multiple candidate peaks based on the extreme points in the local curvature of the multiple frequency points obtained after frequency sweeping of the ultra-high voltage equipment, the method further includes: Store multiple candidate peaks in a temporary peak list; Calculate the frequency difference between two adjacent candidate peaks in the temporary peak list. If the frequency difference is less than twice the minimum step size used in the current frequency sweep process, then the two adjacent candidate peaks are determined to be a suspected merged peak region. Within the suspected merged peak region, a second scan is performed with a preset scan step size. The local curvature of each frequency point obtained by the second scan is calculated based on the actual scan step size. When the local curvature of a frequency point is greater than the dynamic curvature threshold and the current value of the frequency point is less than the current values ​​of its two adjacent frequency points, the frequency point is determined as the valley. If the frequency points on both sides of the valley meet the candidate peak conditions, then the maximum frequency points on both sides of the valley are stored as candidate peaks in the temporary peak list. Sort all candidate peaks in the temporary peak list in descending order of current value.

[0050] Multiple candidate peaks are sorted by current value to obtain a temporary peak list. The complex internal structure of UHV equipment may cause two narrowband resonant peaks to be extremely close in frequency, with the spacing even less than twice the encrypted frequency sweep step size. In this case, although the temporary peak list records two adjacent candidate peaks, it is impossible to confirm whether these two adjacent candidate peaks are independent twin peaks or spurious splits of the same resonant peak due to noise or insufficient sampling because the frequency point at the valley bottom was not collected or identified.

[0051] Perform spacing analysis on adjacent candidate peaks in the provisional peak list. Calculate the frequency difference between two adjacent candidate peaks. ,like ( If the minimum step size used in the current frequency sweep process is used, then two adjacent candidate peaks are determined to be suspected merging peak regions. Within the suspected merging peak regions, the frequency sweep step size is further reduced to a supplementary sweep step size of 0.2Hz for a second supplementary sweep. After the supplementary sweep is completed, the local curvature of the suspected merging peak regions is recalculated. When the local curvature of a frequency point is greater than the dynamic curvature threshold, and the current value of the frequency point is simultaneously less than the current values ​​of its two adjacent frequency points, the frequency point is determined to be a valley. If the frequency points on both sides of the valley meet the candidate peak conditions, then the maximum frequency points on both sides of the valley are stored as candidate peaks in a temporary peak list, and the original merging peak region record is removed. All candidate peaks in the temporary peak list are sorted in descending order of current value. The candidate peak condition indicates that when the local curvature of the second frequency point is greater than the dynamic curvature threshold, and the current value of the second frequency point is simultaneously greater than the current values ​​of its preceding and following frequency points, the second frequency point is determined to be a candidate peak. The p-th candidate peak contains three attributes: frequency. Effective current value Local curvature Local curvature This reflects the sharpness of the resonance peak. A larger peak value indicates a narrower peak bandwidth and a higher quality factor, requiring a smaller step size and a longer sampling time during subsequent fine scanning. The candidate peak with the largest amplitude in the temporary peak list is marked as the primary resonant peak, and the rest are secondary resonant peaks. For repeated peaks with a frequency difference of less than 0.2Hz, they are automatically merged into the same candidate peak, retaining the one with the larger amplitude. The final output temporary peak list completely records all potential resonant points of the UHV equipment in its current state.

[0052] S14. Perform fine scanning on at least some of the candidate peaks among the multiple candidate peaks to obtain the resonant frequency of each candidate peak after fine scanning, and determine the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency, wherein the main resonant frequency is the resonant frequency for conducting the withstand voltage test.

[0053] In one embodiment, at least a portion of the candidate peaks from a plurality of candidate peaks are subjected to fine scanning to obtain the resonant frequency of each finely scanned candidate peak, including: For each candidate peak in the sorted temporary peak list, the current value of each frequency point is collected sequentially within the fine scan range corresponding to each candidate peak with a preset fixed step size; the fine scan range corresponding to each candidate peak is: with the frequency value corresponding to each candidate peak as the center, extending to both sides of a preset frequency range; For each candidate peak, the frequency points and their corresponding current values ​​collected within the fine scan range are fitted using a Lorentz curve, and the peak frequency of the fitted curve is taken as the resonant frequency of each candidate peak.

[0054] Specifically, the resonant frequency corresponding to the candidate peak with the largest current value is determined as the main resonant frequency, including: Select the candidate peak with the largest current value from all candidate peaks, and take the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency.

[0055] For each candidate peak in the sorted temporary peak list, within the fine scan range corresponding to each candidate peak (e.g., extending 2Hz to both sides of the frequency value corresponding to each candidate peak), with a fixed step size of 0.1Hz, the current value at each frequency point is collected sequentially. For the frequency points and corresponding current values ​​collected within the fine scan range corresponding to each candidate peak, a Lorentz curve is used for curve fitting. The peak frequency of the fitted curve is taken as the resonant frequency of each candidate peak. The precise resonant frequencies of all candidate peaks are output to the test report. The candidate peak with the largest current value is selected from all candidate peaks, and the resonant frequency corresponding to the candidate peak with the largest current value is taken as the main resonant frequency. The main resonant frequency is used as the resonant frequency for the subsequent formal withstand voltage test.

[0056] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0057] This application also provides an intelligent ultra-high voltage series resonant withstand voltage test platform, such as... Figure 2 As shown, the platform includes: The frequency sweep module 21 is used to sweep the frequency of the UHV equipment. During the frequency sweep process, it analyzes the amplitude deviation between the current frequency point and its neighboring frequency points to obtain the amplitude change rate of the current frequency point. The first determining module 22 is used to determine the back-off distance and target step size based on the current frequency sweep step size and reference bandwidth if the amplitude change rate of the current frequency point is not less than the trigger threshold and the amplitude change rate of the current frequency point is less than the amplitude change rate of the adjacent frequency point, or the amplitude change rate of the current frequency point is less than the trigger threshold and the current value of the current frequency point or the current value of the adjacent frequency point exceeds a preset current threshold, back off from the current frequency point by the back-off distance, and continue sweeping the frequency with the target step size; The second determining module 23 is used to determine multiple candidate peaks based on the extreme points in the local curvature of multiple frequency points among multiple frequency points obtained after frequency sweeping of the UHV equipment. The test module 24 is used to perform fine scanning on at least some of the candidate peaks among multiple candidate peaks to obtain the resonant frequency of each candidate peak after fine scanning, and to determine the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency, which is the resonant frequency for conducting the withstand voltage test.

[0058] For the platform embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The platform embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs.

[0059] Figure 3 This is a schematic diagram of the structure of an electronic device according to an example embodiment of this application. The electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor. When the processor executes the computer program, it implements the method described in any of the above embodiments. Figure 3 The electronic device 30 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0060] like Figure 3 As shown, the electronic device 30 can be manifested as a general-purpose computing device, such as a server device. The components of the electronic device 30 may include, but are not limited to: at least one processor 31, at least one memory 32, and a bus 33 connecting different system components (including memory 32 and processor 31).

[0061] Bus 33 includes a data bus, an address bus, and a control bus.

[0062] The memory 32 may include volatile memory, such as random access memory 321 and / or cache memory 322, and may further include read-only memory 323.

[0063] The memory 32 may also include a program tool 325 (or utility) having a set (at least one) program module 324, such program module 324 including but not limited to: an operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0064] The processor 31 executes various functional applications and data processing, such as the methods provided in any of the above embodiments, by running computer programs stored in the memory 32.

[0065] Electronic device 30 can also communicate with one or more external devices 34 (e.g., keyboard, pointing device, etc.). This communication can be made through input / output interface 35. Furthermore, electronic device 30 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public network, such as the Internet) via network adapter 36. As shown, network adapter 36 communicates with other modules of electronic device 30 via bus 33. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with electronic device 30, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems.

[0066] It should be noted that although several units / modules or sub-units / modules of the electronic device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided and embodied by multiple units / modules.

[0067] This application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method provided in any of the above embodiments.

[0068] The readable storage medium may be more specifically adopted, including but not limited to: portable disk, hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.

[0069] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0070] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the method described in any of the above embodiments.

[0071] The program code for executing the computer program product of this application can be written in any combination of one or more programming languages. The program code can be executed entirely on the user device, partially on the user device, as a standalone software package, partially on the user device and partially on a remote device, or entirely on a remote device.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.

[0074] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

Claims

1. An intelligent ultra-high voltage series resonant withstand voltage test method, characterized in that, The method includes: Frequency sweeping is performed on the ultra-high voltage equipment. During the frequency sweeping process, the amplitude deviation between the current frequency point and its neighboring frequency points is analyzed to obtain the amplitude mutation rate of the current frequency point. If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, the back-off distance and target step size are determined according to the current sweep step size and reference bandwidth, the back-off distance is reversed from the current frequency point, and the sweep frequency is continued with the target step size; After completing the frequency sweep of the UHV equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points. At least some of the candidate peaks among the multiple candidate peaks are finely scanned to obtain the resonant frequency of each finely scanned candidate peak, and the resonant frequency corresponding to the candidate peak with the largest current value is determined as the main resonant frequency, which is the resonant frequency for the withstand voltage test.

2. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, Before performing frequency sweeping on the UHV equipment and analyzing the amplitude deviation between the current frequency point and its neighboring frequency points during the frequency sweeping process to obtain the amplitude mutation rate of the current frequency point, the method further includes: The UHV equipment is pre-scanned using a preset pre-scanning step size to obtain pre-scanning data; Calculate the amplitude change rate of each pair of adjacent frequency points based on the ratio of the current difference between each pair of adjacent frequency points in the pre-scan data to the pre-scan step size; Calculate the mean of the amplitude change rate of multiple pairs of adjacent frequency points to obtain the average amplitude change rate.

3. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, The frequency sweeping of the ultra-high voltage equipment, analyzing the amplitude deviation between the current frequency point and its neighboring frequency points during the frequency sweeping process to obtain the amplitude change rate of the current frequency point, includes: The frequency of the UHV equipment is swept with a sweep step size. The current value at the current frequency point and the current value at its neighboring frequency points are collected. Based on the collected current time-domain waveform, the effective current value at the current frequency point and the effective current value at its neighboring frequency points are calculated to obtain the effective current value at the current frequency point and the effective current value at its neighboring frequency points. The sweep step size is a preset initial step size or a step size determined by the previous back-off operation. Calculate the absolute difference between the effective current values ​​of the current point and its neighboring frequency points to obtain the current difference value, and calculate the ratio of the current difference value to the sweep step size to obtain the amplitude change rate of the current frequency point; the neighboring frequency points of the current frequency point are its previous frequency points.

4. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, If the amplitude mutation rate at the current frequency point is not less than the trigger threshold and the amplitude mutation rate at the current frequency point is less than the amplitude mutation rate at the neighboring frequency points, or the amplitude mutation rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the neighboring frequency point exceeds a preset current threshold, the backoff distance and target step size are determined based on the current sweep step size and reference bandwidth, including: If the amplitude change rate at the current frequency point is not less than the trigger threshold and the amplitude change rate at the current frequency point is less than the amplitude change rate at the adjacent frequency point, or if the amplitude change rate at the current frequency point is less than the trigger threshold and the current value at the current frequency point or the current value at the adjacent frequency point exceeds the preset current threshold, the reference bandwidth is determined based on the peak current value and the amplitude change rate at the current frequency point; the peak current value indicates the maximum current value among all frequency points from the start of the frequency sweep to the current frequency point. The backoff distance is determined based on the larger of half the current sweep step size and the reference bandwidth. The target step size is determined based on the smaller of one-third of the current sweep step size and one-quarter of the reference bandwidth.

5. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, The step of retreating the retreat distance from the current frequency point and continuing frequency sweeping with the target step size includes: Move the current frequency point towards a lower frequency direction by the back-off distance, and use the reached frequency point as the back-off point; Starting from the backtracking point, continue performing the frequency sweep with the target step size.

6. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, Among the multiple frequency points obtained after frequency sweeping of the UHV equipment, multiple candidate peaks are determined based on the extreme points in the local curvature of the multiple frequency points, including: After completing the frequency sweep of the UHV equipment, among the multiple frequency points obtained, for three frequency points continuously collected with the same phase length, the absolute difference between the sum of the current values ​​of the first frequency point and the third frequency point and twice the current value of the second frequency point is calculated to obtain the discrete second derivative of the second frequency point; where the second frequency point is the middle frequency point of the three frequency points, and the first and third frequency points are the frequency points before and after the second frequency point, respectively. The product of the square of the corresponding sweep step size and the discrete second derivative at the second frequency point is calculated to obtain the local curvature at the second frequency point; the local curvature is used to characterize the degree of bending of the curve of the current value changing with frequency at the second frequency point. When the local curvature of the second frequency point is greater than the dynamic curvature threshold, and the current value of the second frequency point is greater than the current values ​​of its two adjacent frequency points, the second frequency point is determined as a candidate peak; the dynamic curvature threshold is determined based on the average of the local curvatures of all frequency points before the second frequency point.

7. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 6, characterized in that, After determining multiple candidate peaks based on the extreme points in the local curvature of the multiple frequency points obtained after frequency sweeping of the UHV equipment, the process further includes: Store multiple candidate peaks in a temporary peak list; Calculate the frequency difference between two adjacent candidate peaks in the temporary peak list. If the frequency difference is less than twice the minimum step size used in the current frequency sweep process, then the two adjacent candidate peaks are determined to be a suspected merged peak region. Within the suspected merged peak region, a second scan is performed with a preset scan step size, and the local curvature of each frequency point obtained by the scan is calculated. When the local curvature of a frequency point is greater than the dynamic curvature threshold, and the current value of the frequency point is simultaneously less than the current values ​​of its two adjacent frequency points, the frequency point is determined as the valley. If the frequency points on both sides of the valley meet the candidate peak conditions, then the maximum frequency points on both sides of the valley are stored as candidate peaks in the temporary peak list. Sort all candidate peaks in the temporary peak list in descending order of current value.

8. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 7, characterized in that, The step of performing fine scanning on at least a portion of the candidate peaks from a plurality of candidate peaks to obtain the resonant frequency of each finely scanned candidate peak includes: For each candidate peak in the sorted temporary peak list, the current value of each frequency point is collected sequentially within the fine scan range corresponding to each candidate peak with a preset fixed step size; the fine scan range corresponding to each candidate peak is: with the frequency value corresponding to each candidate peak as the center, extending to both sides of a preset frequency range; For each candidate peak, the frequency points and their corresponding current values ​​collected within the fine scan range are fitted using a Lorentz curve, and the peak frequency of the fitted curve is taken as the resonant frequency of each candidate peak.

9. The intelligent ultra-high voltage series resonant withstand voltage test method as described in claim 1, characterized in that, The step of determining the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency includes: Select the candidate peak with the largest current value from all candidate peaks, and take the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency.

10. An intelligent ultra-high voltage series resonant withstand voltage test platform, characterized in that, The platform includes: The frequency sweep module is used to sweep the frequency of UHV equipment. During the frequency sweep process, it analyzes the amplitude deviation between the current frequency point and its neighboring frequency points to obtain the amplitude change rate of the current frequency point. The first determining module is used to determine the back-off distance and target step size based on the current frequency sweep step size and reference bandwidth if the amplitude change rate of the current frequency point is not less than the trigger threshold and the amplitude change rate of the current frequency point is less than the amplitude change rate of the adjacent frequency point, or the amplitude change rate of the current frequency point is less than the trigger threshold and the current value of the current frequency point or the current value of the adjacent frequency point exceeds a preset current threshold. The module then backs off the current frequency point by the back-off distance and continues to sweep the frequency with the target step size. The second determining module is used to determine multiple candidate peaks based on the extreme points in the local curvature of multiple frequency points among multiple frequency points obtained after frequency sweeping of the UHV equipment. The test module is used to perform fine scanning on at least some of the candidate peaks among multiple candidate peaks to obtain the resonant frequency of each candidate peak after fine scanning, and to determine the resonant frequency corresponding to the candidate peak with the largest current value as the main resonant frequency, which is the resonant frequency for conducting the withstand voltage test.

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