High and low voltage frequency converter test system

Abstract

The invention relates to the technical field of electrical parameter testing, in particular to a high-low voltage frequency converter testing system which comprises a sampling point calibration module, a frequency cross-grade identification module, a current response re-sequencing module, a dynamic interference blocking module and an operation parameter output module. According to the method, the amplitude of the voltage sampling point is mapped into the trigonometric function curve, the waveform trend is deduced in combination with the amplitude change angle, a time delay calibration mechanism based on periodic trend identification is established, and the sampling point time sequence precision in different gear switching scenes can be effectively adapted. According to a combined judgment mode of the current rise rate direction and the frequency jump amplitude, a cross-cycle dynamic judgment path is constructed, a frequency jump index can be identified from a non-stable operation state, and the perception capability of a non-linear operation behavior is improved. A current response sorting reconstruction process is introduced, and the sorting matching capability of inconsistent response sequences is enhanced through cross analysis of frequency gears, current response directions and load states.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical parameter testing, and particularly to a high and low voltage frequency converter testing system. Background Art

[0002] The technical field of electrical parameter testing includes related technical content for measuring and monitoring parameters such as voltage, current, frequency, power, and impedance involved in the operation of electrical equipment. The core content of this technical field is to obtain and analyze different forms of electrical parameters in an electrical system through various measurement means and instrument equipment, so as to comprehensively master the performance status, safety, and operating conditions of the equipment.

[0003] Among them, a high and low voltage frequency converter testing system refers to a complete set of testing technical solutions for measuring and evaluating the electrical parameters of frequency converter equipment with different voltage levels. It covers the testing items of parameters such as voltage, current, frequency, and power factor of high and low voltage frequency converters in the output operating state. Specifically, voltage and current sensors are set to collect various signals. After filtering power frequency noise and instantaneous voltage fluctuations through an anti-interference circuit, synchronous data acquisition is completed by an embedded sampling controller at a preset sampling period, and the measurement data is exported to a testing platform through a standardized interface for analysis.

[0004] The prior art relies on a preset sampling period to complete synchronous data acquisition, lacking a dynamic recognition mechanism for sampling points in different waveform change stages. As a result, in scenarios where the voltage waveform deviates or the frequency changes greatly, the sampling time points cannot effectively match the key change areas of the signal, leading to sampling offset problems. Only relying on voltage and current sensors for acquisition and anti-interference filtering circuits to reduce interference, without establishing an interference determination and isolation mechanism at the sampling point level, makes random noise signals remain in the data record, affecting the subsequent parameter accuracy. The measurement data is output in units of cycles, lacking the recognition and structured expression of the timing characteristics of behaviors such as gear shifting and dynamic changes in current response, resulting in fuzzy presentation of operating state information and being unable to effectively reflect the operating logic of the frequency converter under dynamic working conditions. For example, in the state of frequency gear crossing or current response lag, the prior art cannot dynamically adjust the data sequence, only forming static acquisition data output, which limits the accuracy and pertinence of subsequent debugging and evaluation. The overall technical path lacks a multi-dimensional judgment and periodic recombination mechanism driven by data logic, which is likely to cause incomplete coverage of evaluation indicators for the detailed behaviors of the system. Summary of the Invention

[0005] The purpose of the present invention is to solve the disadvantages existing in the prior art, and to propose a high and low voltage frequency converter testing system.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions: A high and low voltage frequency converter testing system includes: The sampling point calibration module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side of the working state cycle of the high- and low-voltage frequency converter, fits a triangular curve, calculates the change angle to judge the waveform trend, corrects the sampling trigger time, and generates a sampling point delay correction result; The frequency shift identification module calculates the operating frequency and the current rise rate based on the sampling point delay correction result, judges the frequency shift state and calibrates the shift index, and generates a frequency shift identification result; The current response reordering module obtains the change information of the current frequency range based on the frequency shift identification result, compares the current current response with the frequency change trend, rearranges the sampling order, and generates a current response rearrangement result; The dynamic blocking interference module obtains the voltage and current sampling point sequences after reordering the current response rearrangement result, calculates the synchronization rate and judges whether the frequency difference exceeds the limit, identifies and eliminates the interference sampling points, and generates a signal interference isolation result; The operating parameter output module classifies and outputs the power, frequency, and current data of each cycle based on the signal interference isolation result and summarizes them by cycle, and generates a set of cycle operating state parameters.

[0007] As a further solution of the present invention, the sampling point delay correction result includes an expected trigger angle, a time deviation amount, and a correction timestamp. The frequency shift identification result is specifically a gear shift index, a frequency jump amplitude, and a reverse identification. The current response rearrangement result includes a sampling order adjustment table, a current feature mapping, and a frequency gear correspondence. The signal interference isolation result specifically refers to the interference point position, the frequency difference mark, and the channel shielding state. The set of cycle operating state parameters includes cycle power indicators, frequency fluctuation information, and current statistical characteristics.

[0008] As a further solution of the present invention, the sampling point calibration module includes: The voltage sampling and waveform processing sub-module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side of the working state cycle of the high- and low-voltage frequency converter, maps them to a trigonometric function curve, and uses the formula: ; Calculate the voltage amplitude change angle ; Among them, represents the high-voltage side voltage amplitude, represents the low-voltage side voltage amplitude, represents the high-voltage side sampling time, represents the low-voltage side sampling time; The waveform change trend judgment sub-module judges the change trend of the current waveform, including the rising section or the falling section, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the change trend of the current waveform, the expected sampling point is deduced, and the waveform change trend is generated; The sampling point correction sub-module calculates the time delay between the expected sampling point and the currently set sampling point according to the waveform change trend. If the delay exceeds the preset time threshold, it corrects the sampling point trigger time of the current cycle to generate a sampling point correction result.

[0009] As a further solution of the present invention, the frequency gear shift identification module includes: The frequency calculation sub-module extracts the time stamp and corresponding frequency change information of each sampling point within the current cycle based on the sampling point delay correction result, calls the current values of the current at multiple consecutive sampling points and adjacent sampling points in the current cycle, and calculates the operating frequency and current rise rate of the frequency converter within the current cycle; The gear shift state judgment sub-module extracts the average frequency value and current rise rate direction information of the previous cycle gear based on the operating frequency and current rise rate of the frequency converter within the current cycle, compares the frequency change amplitude of the current cycle with twice the average frequency of the previous cycle gear, and judges whether the direction of the current rise rate is reversed, filters the sampling cycles that meet the two conditions, and obtains the frequency gear shift trigger state; The index position calibration sub-module locates the position of the frequency gear shift trigger state in the current cycle sampling sequence, calculates the change rate and offset of the current sampling point during the frequency mutation process based on the frequency change amplitude value of the previous cycle, maps the index number of the sampling point, obtains the starting position of the mutation characteristics, and generates a frequency gear shift identification result.

[0010] As a further solution of the present invention, the current response reordering module includes: The frequency change and current comparison sub-module obtains the change information of the current frequency gear based on the frequency gear shift identification result, compares the current response rise rate, operating frequency change direction, and the current waveform of the previous cycle by comparing the current response rise rate with the operating frequency change direction. If the current rise direction is consistent with the frequency change direction, the time series is not adjusted. If not, it analyzes whether it is necessary to adjust the time series of the sampling points to generate an adjustment judgment result; The response order adjustment sub-module analyzes the current frequency gear and load characteristics according to the adjustment judgment result, based on the current frequency gear, load state, and current characteristics of the frequency converter, judges the relationship between the current response mode and frequency switching, and adjusts the current response order according to the obtained information, rearranges the sampling point time series, and generates a current response rearrangement result.

[0011] As a further solution of the present invention, the dynamic blocking interference module includes: The main frequency extraction and synchronization calculation sub-module obtains the voltage and current sampling point sequences after reordering the current response rearrangement result, extracts the main frequency components of each group of sampling values, and for adjacent sampling points of current and voltage and , using the formula: ; Calculate the synchronization rate of adjacent sampling points ; wherein, and respectively represent the main frequencies of the first current sampling point and the adjacent second current sampling point ; and respectively represent the main frequencies of the first voltage sampling point and the second voltage sampling point ; The interference signal judgment sub-module judges the synchronization rate of the adjacent sampling points of the main frequency components. If the synchronization rate of a certain sampling point decreases and the frequency difference exceeds the set interference recognition threshold, it is determined that the sampling point is the point where the interference signal is located, and the sampling point with interference characteristics is identified to generate an interference signal judgment result; The interference signal isolation sub-module cuts off the interference channel of the sampling point where the interference signal is located based on the interference signal judgment result, and readjusts the remaining sampling point sequence to generate a signal interference isolation result.

[0012] As a further solution of the present invention, the operating parameter output module includes: The operating state parameter extraction sub-module obtains the power of the voltage and current sampling points that are not interfered within the period based on the signal interference isolation result, and extracts operating state parameters such as the peak and average values of the current and voltage to obtain voltage and current state data; Summarize all the voltage and current state data, classify and output the power, frequency and current data of each period. By sorting out the voltage and current data in each period, extract the power, frequency, peak current and voltage, and average current and voltage of each period to generate a set of periodic operating state parameters.

[0013] Compared with the prior art, the advantages and positive effects of the present invention are as follows: In the present invention, by mapping the amplitude of the voltage sampling point to a trigonometric function curve, combining the angle of amplitude change to deduce the waveform trend, a time delay calibration mechanism based on periodic trend recognition is established, which can effectively adapt to the sampling point timing accuracy in different gear switching scenarios. According to the combined judgment method of the current rising rate direction and the frequency jump amplitude, a cross-cycle dynamic judgment path is constructed, which can identify the frequency mutation index from the non-steady operation state and enhance the perception ability of nonlinear operation behavior. The current response sorting reconstruction process is introduced. Through the cross-analysis of the frequency gear, the current response direction, and the load state, the sorting and matching ability of inconsistent response sequences is enhanced, ensuring the continuity and logical consistency of data timing. In the interference judgment process, a dual-parameter combination mechanism of the main frequency difference and the synchronous rate decrease is used to achieve the accurate identification and elimination of interference points, effectively isolating random interference signals and improving the stability of data quality. In the operation parameter output stage, through multi-cycle statistics based on the time axis, various power and current states are classified according to the time structure, realizing the continuous expression of the state fluctuation trend and enhancing the adaptability of test data to dynamic evaluation scenarios. The above processing logic realizes a continuous closed-loop from data acquisition, interference elimination to feature output in multi-cycle operation. Based on the recognition and structure rearrangement method driven by dynamic behavior, it strengthens the systematic analysis and periodic expression ability of the complex response characteristics of the frequency converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is the system flow chart of the present invention; Figure 2 is the flow chart of the sampling point calibration module of the present invention; Figure 3 is the flow chart of the frequency cross-gear recognition module of the present invention; Figure 4 is the flow chart of the current response reordering module of the present invention; Figure 5 is the flow chart of the dynamic blocking interference module of the present invention; Figure 6 is the flow chart of the operation parameter output module of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, in the description of the present invention, the meaning of "a plurality of" is two or more unless otherwise specifically defined.

[0017] Please refer to Figure 1 , a high and low voltage frequency converter test system includes: The sampling point calibration module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side of the working state cycle of the high and low voltage frequency converter, maps the continuous voltage amplitudes into a trigonometric function curve, calculates the change angle of the voltage amplitude, judges the current waveform change trend, including the rising section or the falling section, compares the peak voltage of the previous cycle with the current waveform change trend, calculates the expected sampling point, calculates the time delay between the expected sampling point and the current set sampling point. If the delay exceeds the preset time threshold, the sampling point trigger time of the current cycle is corrected to generate a sampling point delay correction result; The frequency shift identification module, based on the sampling point delay correction result, obtains the working frequency and the current rising rate of the frequency converter within the current cycle. The working frequency includes the switching between the high-frequency range and the low-frequency range. If the working frequency change in the current cycle exceeds twice the average frequency of the previous cycle gear, and the direction of the current rising rate reverses, it is identified as the operating state of frequency shift. According to the frequency change amplitude of the previous cycle, the index position of the current frequency shift is calibrated to generate a frequency shift identification result; The current response reordering module obtains the change information of the current frequency gear based on the frequency shift identification result, judges whether it is necessary to adjust the time sequence of the sampling points by comparing the current rising rate of the current response, the working frequency change direction, and the current waveform of the previous cycle, and rearranges the response sequence according to the current frequency gear, load state, and current characteristics of the frequency converter according to the judgment result to generate a current response rearrangement result; The dynamic blocking interference module obtains the voltage and current sampling point sequences after reordering the current response rearrangement result, extracts the main frequency components of each group of sampling values, calculates the synchronization rate of adjacent sampling points, and judges the frequency difference of the main frequency components. If the synchronization rate of a certain sampling point decreases and the frequency difference exceeds the set interference identification threshold, it is determined that the sampling point is the point where the interference signal is located, the interference channel of the target sampling point is cut off, and it is removed from the sampling sequence to generate a signal interference isolation result; Based on the signal interference isolation result, the operating parameter output module obtains the undisturbed voltage and current sampling points within the period for power, as well as the peak and average values of current and voltage and other operating state parameters. It summarizes the voltage and current states of all periods according to the time axis, classifies and outputs the power, frequency, and current data of each period, generates a set of periodic operating state parameters, which serves as the output basis for the test phase and is used for subsequent analysis, debugging, and system evaluation; The sampling point delay correction result includes the expected trigger angle, time deviation amount, and corrected timestamp. The frequency cross-range identification result specifically includes the gear shift index, frequency jump amplitude, and reverse identification. The current response rearrangement result includes the sampling order adjustment table, current feature mapping, and frequency gear correspondence. The signal interference isolation result specifically refers to the interference point position, frequency difference mark, and channel shielding state. The set of periodic operating state parameters includes periodic power indicators, frequency fluctuation information, and current statistical characteristics.

[0018] Please refer to Figure 2 , the sampling point calibration module includes: The voltage sampling and waveform processing sub-module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side during the working state period of the high-low voltage frequency converter, maps them to trigonometric function curves, and uses the formula: ; Calculate the voltage amplitude change angle ; Among them, represents the high-voltage side voltage amplitude, with the unit of volt (V), represents the low-voltage side voltage amplitude, with the unit of volt (V), represents the high-voltage side sampling time, with the unit of second (s), represents the low-voltage side sampling time, with the unit of second (s).

[0019] First, it is necessary to obtain the voltage amplitudes of the high-voltage side and the low-voltage side. This process converts the two voltage signals into digital signals through voltage sampling equipment for subsequent processing. In practical applications, for example, for a device system with a high-voltage side voltage of 220V and a low-voltage side voltage of 110V, through the sampling module, the numerical values of the voltage amplitudes can be obtained. Next, by mapping these voltage amplitudes to trigonometric function curves, the change pattern of the voltage amplitudes can be obtained. Suppose at a certain moment, the high-voltage side voltage amplitude of the device is 200V, and the low-voltage side voltage amplitude is 180V. According to the formula, it can be mapped using trigonometric function formulas to obtain the change trajectory of the voltage amplitudes. Then, using these curve data, calculate the voltage amplitude change angle. The formula is as follows: ; This formula is used to calculate the angle at which the voltage amplitude changes with time. The core lies in measuring the steepness of the voltage waveform change through the ratio between the voltage change amount and the time change amount.

[0020] Let the high - voltage voltage amplitude , the low - voltage voltage amplitude , the high - voltage side sampling time , the low - voltage side sampling time , substituting into the formula gives: Finally, the voltage amplitude change angle is obtained as 89.4°, which provides basic data for the subsequent analysis of the waveform change trend.

[0021] The waveform change trend judgment sub - module judges the change trend of the current waveform, including the rising segment or the falling segment, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the current waveform change trend, the expected sampling point is calculated and the waveform change trend is generated. Based on the calculated voltage amplitude change angle (89.4°), the change trend of the current waveform is then judged. The voltage amplitude change angle reflects the degree of change of the voltage amplitude on the time axis. When the voltage amplitude change angle is very large, it indicates that the voltage waveform has changed significantly. In this case, if the angle is close to 90°, it can be inferred that the current waveform is in a stage of drastic change, and it is usually a relatively sharp transition in either the rising segment or the falling segment. For example, if the voltage amplitude increases from 180V to 200V and the calculated voltage amplitude change angle is 89.4°, then it can be speculated that the waveform is in the rising segment at this time because the change amplitude of the voltage amplitude is very large and the angle is close to 90°, which means the waveform change is relatively drastic. Similarly, if the voltage amplitude decreases from 200V to 180V and the voltage amplitude change angle is 89.4°, then it can be judged that the waveform is in the sharp - falling segment. In this way, the change trend of the voltage waveform can be judged, and then the position of the expected sampling point can be calculated. Suppose the peak voltage of the previous cycle is 220V and the current voltage amplitude change trend is the falling segment, then the position of the expected sampling point will be calculated in the lower half of the waveform decline, so as to ensure the reasonable distribution of voltage sampling points. Through this method, the waveform change trend can be obtained and then used for subsequent sampling point correction operations.

[0022] The sampling point correction sub - module calculates the time delay between the expected sampling point and the current set sampling point according to the waveform change trend. If the delay exceeds the preset time threshold, the sampling point trigger time of the current cycle is corrected to generate the sampling point correction result.

[0023] By calculating the time delay between the expected sampling point and the currently set sampling point. The calculation of the time delay is achieved by comparing the deviation between the set sampling point position and the actual waveform change trend. Suppose the currently set sampling point is T = 1.5s, and the expected sampling point deduced from the waveform change trend is T = 1.7s, then the time delay between the two is 0.2s. If this time delay exceeds the preset time threshold, correction becomes necessary. The set time threshold is 0.1s, so since the 0.2s delay exceeds the threshold, it is necessary to correct the sampling point trigger time for the current cycle. This correction is achieved by adjusting the sampling point trigger time to be as close as possible to the expected sampling point to ensure the accuracy of the voltage sampling point. Finally, the result of the correction will generate the sampling point correction result, providing a more accurate time point for subsequent data acquisition and processing.

[0024] Please refer to Figure 3 , the frequency cross-range identification module includes: Based on the sampling point delay correction result, the frequency calculation sub-module extracts the time stamp and corresponding frequency change information of each sampling point within the current cycle, calls the current cycle's continuous multiple sampling points and the current values of adjacent sampling points, and uses the formula: ; Calculate the operating frequency of the frequency converter within the current cycle and the current rise rate ; Among them, represents the frequency value of the th sampling point, represents the total number of sampling points within the current cycle, represents the current value of the th sampling point, represents the current value of the th sampling point, represents the time stamp corresponding to the th sampling point, represents the time stamp corresponding to the th sampling point, represents the absolute value of the current rise rate of the th sampling interval.

[0025] First, it is necessary to obtain the sampling time series of the current cycle 、the corresponding frequency sampling series , and the current sampling value series , using the frequency average calculation formula ; For example, during the actual execution process, the frequency values of 100 sampling points in the current period are summed one by one. Assuming the frequency values are 48.1, 48.3, 48.6... 50.2 Hz in sequence, and the total sum is 4940 Hz, then: ; represents the average value of the working frequency in the current period. Here, represents the number of sampling points, represents the frequency value of the th sampling point. The calculation logic of this formula is: linearly sum all the sampling frequency values and normalize them by the number of sampling points to quantify the operating frequency level of the frequency converter in a complete period; Subsequently, calculate the current rising rate using the formula: ; Among the continuous sampling points in the current period, extract the change amount between adjacent two current values pair by pair, and divide it by the sampling time interval to reflect the change degree of the current per unit time. At the same time, retain the absolute intensity of the rising rate by taking the absolute value to avoid directional influence, and perform averaging processing on all sections; Illustrated with a numerical example, if the sampling time is every 10 ms, that is s, and the first five groups of current values are: 10.0 A, 10.3 A, 10.6 A, 11.0 A, 11.4 A, then: .

[0026] Then average the above results: ; This value represents the average change rate of the current per unit time in the current period. The larger the value, the more intense the current response; this result shows that the frequency value in the current period is 49.4 Hz and the current rising rate is 35 A / s, thereby generating the frequency and current rising rate in the current period.

[0027] The gear shifting state judgment sub-module extracts the average gear frequency value and the current rising rate direction information of the previous period based on the working frequency and current rising rate of the frequency converter in the current period, compares the frequency change amplitude in the current period with twice the average gear frequency of the previous period, and judges whether the direction of the current rising rate is reversed, filters the sampling periods that meet the two conditions, and obtains the frequency gear shifting trigger state; After calling the frequency and current rising rate in the current period, it is necessary to extract the average gear frequency value of the previous period , which is the same operation as in paragraph 1, that is, sum the sampling frequency value sequence of the previous period and divide it by the number of points. Assuming the frequency data of the previous period is from 45.5 Hz to 46.5 Hz, the total sum is 4600 Hz, and the number of sampling points is 100, then ; Next, calculate the change amplitude of the current cycle frequency , assuming that the maximum value of the current cycle frequency is 53.0 Hz and the minimum value is 47.0 Hz, then: ; To determine whether the current cycle frequency change exceeds twice the average frequency of the previous cycle gear, set the comparison condition as: ; The change amplitude of the current cycle frequency is less than 92.0 Hz, meeting Condition 1, that is, not exceeding twice the reference frequency range; To further refine the judgment of the frequency change amplitude, a calculation method based on proportion is adopted, ; This indicates that the current frequency change amplitude accounts for 13.04% of the average frequency of the previous cycle gear, which is greater than the threshold of 10%, so it meets the conditions for frequency mutation; The change in the direction of the current rise rate also needs to be checked. If the starting current of the current cycle is 15 A and the end value is 12 A, then the current direction is reversed; in the previous cycle, the current increased from 10 A to 12.5 A, and the direction was positive. By comparing the signs of the current change rates: ; Among them, respectively represent the starting and ending current values of the current cycle, with the unit of A; respectively represent the starting and ending times of the current cycle, with the unit of seconds; respectively represent the starting and ending current values of the previous cycle, with the unit of A; respectively represent the starting and ending times of the previous cycle, with the unit of seconds.

[0028] The formula calculates the sign change of the current change rate between the current cycle and the previous cycle. If the signs of the two are opposite (i.e., one is positive and the other is negative), then the direction of the current rise rate is reversed. After meeting the conditions, the current cycle is marked as a cross-gear trigger cycle, and the frequency cross-gear trigger status is obtained.

[0029] The index position calibration sub-module locates the position of the frequency cross-gear trigger status in the current cycle sampling sequence, calculates the change rate and offset of the current sampling point during the frequency mutation process based on the frequency change amplitude value of the previous cycle, maps the index number of the sampling point, obtains the starting position of the mutation characteristics, and generates the frequency cross-gear recognition result; After calling the frequency cross-gear trigger status, it is necessary to further calibrate its specific position in the current cycle sampling sequence. First, extract the frequency change amplitude of the previous cycle , then calibrate the position of the mutation point of the current cycle frequency. Assume that the current cycle frequency mutates from 48.0Hz to 53.0Hz, and calculate the frequency increment between the 60th and 80th sampling points. The increment is ; Therefore, the frequency increment of each sampling point is 0.25Hz; Next, perform proportional calculation through the relative increment and the amplitude of the previous cycle. Assume that the frequency at the 65th point is 49.5Hz and the increment is 1.5Hz, then its relative increment is ; Then calibrate the index position of this point through this ratio as ; This index position indicates the occurrence point of the frequency mutation. Process the frequency points in all mutation intervals of the current cycle through this mapping method, and finally complete the precise calibration of the mutation position to generate the frequency cross-range identification result.

[0030] Please refer to Figure 4 , the current response reordering module includes: The frequency change and current comparison sub-module, based on the frequency cross-range identification result, obtains the change information of the current frequency range. By comparing the rising rate of the current current response, the change direction of the operating frequency, and the current waveform of the previous cycle, compare the rising rate of the current current response with the change direction of the operating frequency. If the current rising direction is consistent with the frequency change direction, the time series is not adjusted. If not, analyze whether it is necessary to adjust the time series of the sampling points to generate an adjustment judgment result; First, it is necessary to obtain the change information of the current frequency range. Next, extract the rising rate of the current response, the change direction of the operating frequency, and the current waveform information of the previous cycle for comparison. Taking the actual implementation as an example, when the frequency converter switches from the low-frequency range to the high-frequency range, its frequency changes from 48Hz to 50Hz, and the current increases accordingly. Assume that the current rising rate in the current cycle is 25A / s, the frequency change amplitude is 2Hz, and the frequency change direction is increasing. In this case, it is necessary to judge whether it is necessary to adjust the sampling time series by comparing the consistency between the current current rising rate and the frequency change direction. If the current rising direction is consistent with the frequency change direction, the sampling point time series does not need to be adjusted. Otherwise, it is necessary to analyze the data of the previous cycle of the current waveform to judge whether there is an overly fast current response speed or mismatched current waveform characteristics, and adjust the sampling time series based on this. For example, if the current waveform of the previous cycle is in a stable state, and the current waveform of the current cycle suddenly changes violently, it indicates that the current response does not match the frequency change and needs to be adjusted. Finally, through these steps, an analysis result of the matching between the current and the frequency is generated to determine whether it is necessary to adjust the sampling point time series.

[0031] The response order adjustment sub-module analyzes the current frequency range, load status, and current characteristics of the frequency converter according to the adjustment judgment result, determines the relationship between the current response mode and frequency switching, adjusts the current response order based on the obtained information, rearranges the time series of sampling points, and generates the current response rearrangement result; According to the matching analysis result of current and frequency obtained in the previous steps, further adjust the response order based on the current frequency range, load status, and current characteristics of the frequency converter. Assume that the current frequency converter is operating in the high-frequency range, the load is in a light-load state, and the current characteristics are relatively stable, then the current response order can be maintained. However, if the load status is heavy, the current characteristics fluctuate, and the frequency cross-range identification result shows that the frequency changes violently, it is necessary to adjust the response order according to the characteristics of the current change. For example, when the frequency quickly switches from 50Hz to 60Hz, the current may not respond in time, resulting in a response lag. At this time, it is necessary to adjust the time series of sampling points. By analyzing the relationship between the current frequency range change and current characteristics, combined with the real-time change of the frequency converter load, rearrange the time series of sampling points to ensure a smooth transition of the current response. In this process, the change amplitude of the frequency and the response speed of the current are the key factors. Finally, generate the current response rearrangement result to ensure that the frequency converter can quickly respond and synchronously adjust the frequency when the load changes.

[0032] Please refer to Figure 5 , the dynamic blocking interference module includes: The main frequency extraction and synchronization calculation sub-module obtains the voltage and current sampling point sequences after reordering the current response rearrangement result, extracts the main frequency components of each group of sampling values, and for adjacent sampling points of current and voltage and , use the formula: ; calculate the synchronization rate of adjacent sampling points ; where and respectively represent the main frequencies of the current sampling points and , and respectively represent the main frequencies of the voltage sampling points and . This formula is used to measure the frequency change synchronization of voltage and current. If the synchronization rate is low, it indicates that the synchronization between voltage and current is poor, and there may be interference signals.

[0033] Obtain the voltage and current sampling point sequences after current response rearrangement, extract the main frequency components of each group of sampling values, and calculate the synchronization rate of adjacent sampling points. Specifically, first, the sampling points of current and voltage are sorted to ensure the consistency of data on the time axis. After that, methods such as Fourier transform are used to extract the main frequency components of each sampling point, obtaining the current and voltage frequency characteristics. Assume the voltage sequence is , and the current sequence is . Extract the corresponding frequencies and for these four sampling points respectively. Then, calculate the synchronization rate of adjacent sampling points. The specific calculation method is as follows: ; For example, assume that the main frequency difference of current between the and sampling points is Hz, and the main frequency difference of voltage is Hz. Substitute these values into the above formula to calculate the synchronization rate. Assume the sum of the frequencies of current and voltage is Hz and , and the synchronization rate is obtained; According to the synchronization rate result, it can be judged that the synchronization of voltage and current at the current sampling point is relatively low, and then it is decided whether further operations are needed, such as adjusting the time series or marking interference signals.

[0034] The interference signal judgment sub-module judges the synchronization rate of adjacent sampling points of the main frequency components. If the synchronization rate of a certain sampling point decreases and the frequency difference exceeds the set interference recognition threshold, then the sampling point is determined to be the point where the interference signal is located, identifying the sampling points with interference characteristics and generating the interference signal judgment result; First, it is necessary to judge the frequency difference of the extracted main frequency components. If it is found during the analysis that the synchronization rate of a certain sampling point decreases significantly and the frequency difference exceeds the set interference recognition threshold, then this sampling point is judged to be the source of the interference signal. The specific operation is as follows: Set an interference recognition threshold. Assume the threshold value is 0.5 Hz. When the frequency difference between the main frequency of current and the main frequency of voltage at a certain sampling point exceeds this threshold value, mark this sampling point as an interference signal point. For example, assume that the main frequency of voltage at the th sampling point is Hz, and the main frequency of current is Hz, then the frequency difference is ; Since the frequency difference If it exceeds the set interference threshold of 0.5 Hz, this sampling point will be determined as an interference signal point, and then a cut-off operation will be performed. Generate an interference signal judgment result and further decide to isolate this signal point.

[0035] Based on the interference signal judgment result, the interference signal isolation sub-module cuts off the interference channel of the sampling point where the interference signal is located, re-adjusts the remaining sampling point sequence, and generates a signal interference isolation result; First, it is necessary to locate the sampling point where the interference signal is located, and then perform the operation of cutting off the interference channel. The specific operation is to remove the sampling point marked as the interference signal from the voltage and current data sequences and exclude its influence from the entire sampling sequence. For example, assume that the th sampling point has been identified as an interference signal point. The operation steps are to delete the data of this sampling point from the sampling data sequence and re-adjust the remaining data to ensure the accuracy of subsequent signal processing. Finally, generate a signal interference isolation result to provide a clean signal sequence for subsequent data processing and ensure the stable operation of the system.

[0036] Please refer to Figure 6 , the operating parameter output module includes: Based on the signal interference isolation result, the operating state parameter extraction sub-module obtains the power of the voltage and current sampling points that are not interfered within the period, and extracts operating state parameters such as the peak and average values of the current and voltage to obtain voltage and current state data; First, filter out the voltage and current sampling point groups that are not marked as interference within the current sampling period from the output sequence. The sampling point sequence needs to correspond to the complete time period within the current control period of the frequency converter to ensure the matching of voltage and current data on the time axis. In practical applications, for example, when sampling a certain frequency converter at a frequency of 1 kHz, 1000 sampling points are obtained. If a total of 50 interference points are removed, then 950 groups of valid data are retained to participate in subsequent operations. Next, extract the voltage and current data in each group of sampling points to analyze their power conditions and state characteristics. The power evaluation is performed based on the single-point product method. Subsequently, identify the voltage and current peaks within the current period. The judgment criterion for the peak is to take the largest value in the sampling sequence. Assume that the voltage sequence within a certain period is; V, and the maximum value of 239 V is the peak voltage of this period. The average value is obtained by dividing the sum of the sampling sequence by the number of data points. For example, the average voltage is; V. The current data is processed in the same way to extract the peak and average values and generate the operating state parameter values.

[0037] Summarize all the voltage and current state data, classify and output the power, frequency, and current data of each period. By organizing the voltage and current data within each period, extract the power, frequency, peak current and voltage, and average current and voltage of each period to generate a set of periodic operating state parameters; Summarize the voltage and current states within all cycles according to the time axis. First, bind the peak voltage, average voltage, peak current, average current calculated for each cycle with the time stamps within the corresponding cycle, and arrange them in chronological order to form a complete cycle sequence data set. Subsequently, number and summarize each group of data according to cycle classification, and output a record of cycle operation parameters including cycle number, power, frequency, and current values. A typical example is as follows: A total of 10 cycles are recorded in a monitoring window, and the sampled data for each cycle has been processed. Then, the corresponding parameters for each cycle are sorted and output according to cycle numbers from 1 to 10. Suppose the power sampling value in cycle 5 fluctuates abnormally, then the parameters for this cycle will be marked separately in the summary table. In addition, the corresponding relationship between the time stamp and the parameters needs to be recorded in the summary result. After all the cycle operation parameters are classified and sorted according to the time axis, they are uniformly summarized and output to form a set of cycle operation state parameters.

[0038] The above is only a preferred embodiment of the present invention, and does not impose other forms of limitations on the present invention. Any person skilled in the relevant art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A high and low voltage frequency converter test system, characterized in that The system includes: The sampling point calibration module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side of the high-low voltage frequency converter during the working state period, fits a triangular curve, calculates the change angle to judge the waveform trend, corrects the sampling trigger time, and generates a sampling point delay correction result; The frequency shift identification module calculates the working frequency and the current rise rate based on the sampling point delay correction result, judges the frequency shift state and calibrates the shift index, and generates a frequency shift identification result; The current response reordering module obtains the change information of the current frequency gear based on the frequency shift identification result, compares the current current response with the frequency change trend, rearranges the sampling order, and generates a current response rearrangement result; The dynamic blocking interference module obtains the voltage and current sampling point sequences after reordering the current response rearrangement result, calculates the synchronization rate and judges whether the frequency difference exceeds the limit, identifies and removes the interference sampling points, and generates a signal interference isolation result; The operating parameter output module classifies and outputs the power, frequency, and current data of each cycle based on the signal interference isolation result and summarizes them by cycle, and generates a set of cycle operating state parameters.

2. The high and low voltage frequency converter test system according to claim 1, characterized in that: The sampling point delay correction result includes an expected trigger angle, a time deviation amount, and a correction timestamp. The frequency shift identification result is specifically a gear shift index, a frequency jump amplitude, and a reverse identification. The current response rearrangement result includes a sampling order adjustment table, a current feature mapping, and a frequency gear correspondence. The signal interference isolation result specifically refers to the interference point position, the frequency difference mark, and the channel shielding state. The set of cycle operating state parameters includes cycle power indicators, frequency fluctuation information, and current statistical characteristics.

3. The high and low voltage frequency converter test system according to claim 2, wherein, The sampling point calibration module includes: The voltage sampling and waveform processing sub-module obtains the voltage amplitudes of the voltage sampling points on the high-voltage side and the low-voltage side of the high-low voltage frequency converter during the working state period, maps them to a trigonometric function curve, and uses the formula: ； Calculate the voltage amplitude change angle ; Among them, represents the high-voltage side voltage amplitude, represents the low-voltage side voltage amplitude, represents the high-voltage side sampling time, represents the low-voltage side sampling time; The waveform change trend judgment sub-module judges the change trend of the current waveform, including the rising section or the falling section, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the change trend of the current waveform, the expected sampling point is deduced, and the waveform change trend is generated; The sampling point correction sub-module calculates the time delay between the expected sampling point and the current set sampling point according to the waveform change trend. If the delay exceeds the preset time threshold, the sampling point trigger time of the current cycle is corrected, and a sampling point correction result is generated.

4. The high and low voltage frequency converter test system according to claim 3, wherein The frequency shift identification module includes: The frequency calculation sub-module extracts the timestamps and the corresponding frequency change information of each sampling point in the current cycle based on the sampling point delay correction result, calls the current cycle's continuous multiple sampling points and the current values of adjacent sampling points, and calculates the working frequency and the current rise rate of the frequency converter in the current cycle; The shift state judgment sub-module extracts the average frequency value and the current rise rate direction information of the previous cycle gear based on the working frequency and the current rise rate of the frequency converter in the current cycle, compares the current cycle frequency change amplitude with twice the average frequency of the previous cycle gear, and judges whether the direction of the current rise rate is reversed. The sampling cycles that meet the two conditions are screened to obtain the frequency shift trigger state; The index position calibration sub-module locates the position of the frequency cross-range trigger state in the current cycle sampling sequence, calculates the change rate and offset of the current sampling point during the frequency mutation process based on the frequency change amplitude value of the previous cycle, maps the index number of the sampling point, obtains the starting position of the mutation characteristics, and generates a frequency cross-range identification result.

5. The high and low voltage frequency converter test system according to claim 4, wherein, The current response reordering module includes: The frequency change and current comparison sub-module obtains the change information of the current frequency range based on the frequency cross-range identification result. By comparing the rising rate of the current response, the change direction of the operating frequency, and the current waveform of the previous cycle, it compares the rising rate of the current response with the change direction of the operating frequency. If the current rising direction is consistent with the frequency change direction, the time series is not adjusted. If not, it analyzes whether it is necessary to adjust the time series of the sampling point and generates an adjustment judgment result. The response order adjustment sub-module analyzes the current frequency range and load characteristics according to the adjustment judgment result, the current frequency range of the frequency converter, the load state, and the current characteristics, judges the relationship between the current response mode and the frequency switching, and adjusts the current response order according to the obtained information, rearranges the sampling point time series, and generates a current response rearrangement result.

6. The high and low voltage converter test system according to claim 5, characterized in that: The dynamic blocking interference module includes: The main frequency extraction and synchronization calculation sub-module obtains the voltage and current sampling point sequences after reordering the re-arranged result of the current response, extracts the main frequency components of each group of sampling values, and for adjacent sampling points of current and voltage and , use the formula: ； Calculate the synchronization rate of adjacent sampling points ; Among them, and respectively represent the main frequencies of the first voltage sampling point and the second voltage sampling point ; and respectively represent the main frequencies of the first voltage sampling point and the second voltage sampling point ; The interference signal judgment sub-module judges the synchronization rate of the adjacent sampling points of the main frequency component. If the synchronization rate of a certain sampling point decreases and the frequency difference exceeds the set interference identification threshold, it is determined that the sampling point is the point where the interference signal is located, identifies the sampling points with interference characteristics, and generates an interference signal judgment result. The interference signal isolation sub-module cuts off the interference channel of the sampling point where the interference signal is located based on the interference signal judgment result, readjusts the remaining sampling point sequence, and generates a signal interference isolation result.

7. The high and low voltage frequency converter test system according to claim 6, wherein, The operating parameter output module includes: The operating state parameter extraction sub-module obtains the power of the voltage and current sampling points that are not interfered within the cycle based on the signal interference isolation result, and extracts operating state parameters such as the peak and average values of the current and voltage to obtain voltage and current state data. Summarize all the voltage and current state data, classify and output the power, frequency, and current data of each cycle. By sorting out the voltage and current data in each cycle, extract the power, frequency, peak current and voltage, and average current and voltage of each cycle, and generate a set of cycle operating state parameters.

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