A testing system for high and low voltage frequency converters

Abstract

This invention relates to the field of electrical parameter testing technology, specifically a high- and low-voltage frequency converter testing system. The system includes: a sampling point calibration module, a frequency cross-range identification module, a current response reordering module, a dynamic interference blocking module, and an operating parameter output module. In this invention, by mapping the voltage sampling point amplitude to a trigonometric function curve and deriving the waveform trend based on the amplitude change angle, a time delay calibration mechanism based on periodic trend identification is established, which can effectively adapt to the sampling point timing accuracy under different range switching scenarios. Based on the joint determination method of current rise rate direction and frequency jump amplitude, a cross-cycle dynamic judgment path is constructed, which can identify frequency change indices from non-stationary operating states, improving the perception capability of nonlinear operating behavior. A current response sorting and reconstruction process is introduced, which enhances the sorting and matching capability of inconsistent response sequences through cross-analysis of frequency range, current response direction, and load state.

Description

Technical Field

[0001] This invention relates to the field of electrical parameter testing technology, and in particular to a high and low voltage frequency converter testing system. Background Technology

[0002] The field of electrical parameter testing technology encompasses the measurement and monitoring of parameters such as voltage, current, frequency, power, and impedance involved in the operation of electrical equipment. The core of this technology lies in acquiring and analyzing different forms of electrical parameters in electrical systems through various measurement methods and instruments, thereby achieving a comprehensive understanding of equipment performance, safety, and operating conditions.

[0003] The high and low voltage frequency converter testing system refers to a complete testing technology solution for measuring and evaluating the electrical parameters of frequency converter equipment at different voltage levels. It covers testing parameters such as voltage, current, frequency, and power factor of high and low voltage frequency converters under output operating conditions. Specifically, it collects various signals by setting up voltage and current sensors, filters out power frequency noise and instantaneous voltage fluctuations through anti-interference circuits, and completes synchronous data acquisition at a preset sampling period through an embedded sampling controller. The measurement data is then exported to the testing platform for analysis via a standardized interface.

[0004] Existing technologies rely on preset sampling periods for synchronous data acquisition, lacking a dynamic identification mechanism for sampling points at different waveform change stages. This leads to sampling time points failing to effectively match key signal change regions in scenarios with significant voltage waveform offsets or frequency variations, resulting in sampling offset issues. Relying solely on voltage and current sensors and anti-interference filtering circuits for interference reduction, without establishing a sampling point-level interference judgment and isolation mechanism, leaves random noise signals in the data records, affecting the accuracy of subsequent parameters. Measurement data is output periodically, lacking the identification and structured representation of timing characteristics such as gear switching and dynamic changes in current response, resulting in ambiguous operating status information and failing to effectively reflect the inverter's operating logic under dynamic conditions. For example, in situations of frequency gear switching or current response lag, existing technologies cannot dynamically adjust the data sequence, only generating static data output, limiting the accuracy and specificity of subsequent debugging and evaluation. The overall technical approach lacks a data logic-driven multi-dimensional judgment and periodic reorganization mechanism, easily leading to incomplete coverage of system details by evaluation indicators. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and propose a high and low voltage frequency converter testing system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a high and low voltage frequency converter testing system includes:

[0007] The sampling point calibration module acquires the voltage amplitude of the voltage sampling points on the high-voltage side and low-voltage side during the working cycle of the high- and low-voltage frequency converter, fits a triangular curve, calculates the changing angle to determine the waveform trend, corrects the sampling trigger time, and generates the sampling point delay correction result.

[0008] Based on the sampling point delay correction result, the frequency cross-gap identification module calculates the operating frequency and current rise rate, determines the frequency cross-gap status and calibrates the cross-gap index, and generates the frequency cross-gap identification result.

[0009] The current response reordering module obtains the change information of the current frequency range based on the frequency cross-range identification result, compares the current current response with the frequency change trend, rearranges the sampling order, and generates the current response reordering result.

[0010] The dynamic interference blocking module obtains the voltage and current sampling point sequence after the current response rearrangement result is reordered, calculates the synchronization rate and determines whether the frequency difference exceeds the limit, identifies and removes interference sampling points, and generates signal interference isolation results.

[0011] Based on the signal interference isolation results, the operation parameter output module classifies and outputs the power, frequency and current data for each cycle and summarizes them by cycle to generate a set of cycle operation status parameters.

[0012] As a further aspect of the present invention, the sampling point delay correction result includes the expected trigger angle, time deviation, and correction timestamp; the frequency cross-gear identification result specifically includes the gear switching index, frequency jump amplitude, and reversal identifier; 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 location, frequency difference marker, and channel shielding status; and the periodic operation status parameter set includes the periodic power index, frequency fluctuation information, and current statistical characteristics.

[0013] As a further aspect of the present invention, the sampling point calibration module includes:

[0014] The voltage sampling and waveform processing submodule acquires the voltage amplitude of the high-voltage and low-voltage side voltage sampling points during the operating cycle of the high- and low-voltage frequency converters, maps them to trigonometric function curves, and uses the formula:

[0015] ;

[0016] Calculate the angle of voltage amplitude change ;

[0017] in, Represents the voltage amplitude on the high-voltage side. Represents the voltage amplitude on the low-voltage side. Represents the sampling time on the high-voltage side. This represents the sampling time on the low-pressure side;

[0018] The waveform change trend judgment submodule determines the current waveform change trend, including rising or falling segments, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the current waveform change trend, it calculates the desired sampling point and generates the waveform change trend.

[0019] The sampling point correction submodule calculates the time delay between the desired sampling point and the currently set sampling point based on the waveform change trend. If the delay exceeds a preset time threshold, the sampling point trigger time of the current period is corrected, and a sampling point correction result is generated.

[0020] As a further aspect of the present invention, the frequency cross-gear recognition module includes:

[0021] Based on the sampling point delay correction result, the frequency calculation submodule extracts the timestamp and corresponding frequency change information of each sampling point in the current cycle, calls the current values ​​of multiple consecutive sampling points and adjacent sampling points in the current cycle, and calculates the operating frequency and current rise rate of the inverter in the current cycle.

[0022] The cross-gear state judgment submodule extracts the average frequency value and current rise rate information of the previous cycle based on the inverter's operating frequency and current rise rate in the current cycle, compares the frequency change amplitude of the current cycle with twice the average frequency of the previous cycle, and determines whether the current rise rate direction is reversed. It then filters the sampling cycles that meet the two conditions to obtain the frequency cross-gear trigger state.

[0023] The index position calibration submodule locates the position of the frequency cross-gap trigger state in the current period sampling sequence, calculates the rate of change and offset of the current sampling point in the frequency change process based on the frequency change amplitude value of the previous period, maps the index number of the sampling point, obtains the starting position of the change characteristic, and generates the frequency cross-gap identification result.

[0024] As a further aspect of the present invention, the current response resequencing module includes:

[0025] The frequency change and current comparison sub-module obtains the change information of the current frequency level based on the frequency cross-level identification result. By comparing the rise rate of the current current response, the direction of change of the working frequency and the current waveform of the previous cycle, it compares the rise rate of the current current response with the direction of change of the working frequency. If the current rise direction matches the frequency change direction, the time series is not adjusted. If they do not match, it analyzes whether the time series of the sampling points needs to be adjusted and generates an adjustment judgment result.

[0026] The response sequence adjustment submodule, based on the adjustment judgment result, analyzes the current frequency range and load characteristics according to the inverter's current frequency range, load status and current characteristics, determines the relationship between the current response mode and frequency switching, adjusts the current response sequence according to the acquired information, rearranges the sampling point time series, and generates the current response rearrangement result.

[0027] As a further aspect of the present invention, the dynamic interference blocking module includes:

[0028] The main frequency extraction and synchronization calculation submodule obtains the reordered voltage and current sampling point sequence after the current response rearrangement result, extracts the main frequency component of each group of sampling values, and calculates the main frequency component for adjacent sampling points of current and voltage.

[0029] and The formula used is:

[0030] ;

[0031] Calculate the synchronization rate of adjacent sampling points ;

[0032] in, and These represent the first current sampling points. and the adjacent second current sampling point main frequency, and These represent the first voltage sampling points. Second voltage sampling point clock speed;

[0033] The interference signal judgment submodule 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, the sampling point is determined to be the location of the interference signal. The sampling point with interference characteristics is identified and the interference signal judgment result is generated.

[0034] Based on the interference signal judgment result, the interference signal isolation submodule cuts off the interference channel of the sampling point where the interference signal is located, readjusts the remaining sampling point sequence, and generates a signal interference isolation result.

[0035] As a further aspect of the present invention, the operating parameter output module includes:

[0036] Based on the signal interference isolation results, the operating status parameter extraction submodule obtains the power of the voltage and current sampling points that are not interfered with within the period, and extracts operating status parameters such as the peak value and average value of the current and voltage to obtain voltage and current status data.

[0037] All voltage and current state data are summarized, and the power, frequency, and current data for each cycle are output in categories. By organizing the voltage and current data in each cycle, the power, frequency, peak current and voltage, as well as the average current and voltage of each cycle are extracted to generate a set of cycle operation state parameters.

[0038] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0039] In this invention, by mapping the voltage sampling point amplitude to a trigonometric function curve and deriving the waveform trend based on the amplitude change angle, a time delay calibration mechanism based on periodic trend identification is established, which can effectively adapt to the sampling point timing accuracy under different gear switching scenarios. Based on the joint determination method of current rise rate direction and frequency jump amplitude, a cross-cycle dynamic judgment path is constructed, which can identify frequency mutation indices from non-stationary operating states, improving the perception capability of nonlinear operating behavior. A current response sorting and reconstruction process is introduced, which enhances the sorting and matching capability of inconsistent response sequences through cross-analysis of frequency gear, current response direction, and load state, ensuring the continuity and logical consistency of data timing. During interference judgment, a dual-parameter combination mechanism of main frequency difference and synchronization rate decrease is used to accurately identify and eliminate interference points, effectively isolating random interference signals and improving data quality stability. In the operating parameter output stage, through multi-cycle statistics based on the time axis, various power and current states are classified according to time structure, realizing continuous expression of state fluctuation trends and enhancing the adaptability of test data to dynamic evaluation scenarios. The above processing logic achieves a continuous closed loop from data acquisition and interference removal to feature output during multi-cycle operation. Based on the dynamic behavior-driven identification and structural rearrangement method, it enhances the systematic analysis and periodic expression capabilities of the complex response characteristics of the frequency converter. Attached Figure Description

[0040] Figure 1 This is a system flowchart of the present invention;

[0041] Figure 2 This is a flowchart of the sampling point calibration module of the present invention;

[0042] Figure 3 This is a flowchart of the frequency cross-gear recognition module of the present invention;

[0043] Figure 4 This is a flowchart of the current response reordering module of the present invention;

[0044] Figure 5 This is a flowchart of the dynamic interference blocking module of the present invention;

[0045] Figure 6 This is a flowchart of the operating parameter output module of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 merely illustrative and not intended to limit the invention.

[0047] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0048] Please see Figure 1 A high- and low-voltage frequency converter testing system includes:

[0049] The sampling point calibration module acquires the voltage amplitude of the voltage sampling points on the high-voltage side and low-voltage side during the working cycle of the high- and low-voltage frequency converter. It maps the continuous voltage amplitude to a trigonometric function curve, calculates the angle of change of the voltage amplitude, and determines the current waveform change trend, including rising or falling segments. It compares the peak voltage of the previous cycle with the current waveform change trend to estimate the desired sampling point. It calculates the time delay between the desired sampling point and the currently set sampling point. If the delay exceeds the preset time threshold, it corrects the sampling point trigger time of the current cycle and generates the sampling point delay correction result.

[0050] The frequency cross-gear recognition module obtains the inverter's operating frequency and current rise rate within the current cycle based on the sampling point delay correction result. The operating frequency includes the switching between high-frequency and low-frequency gears. If the operating frequency change in the current cycle exceeds twice the average frequency of the gear in the previous cycle, and the current rise rate reverses direction, it is identified as a frequency cross-gear operation. Based on the frequency change amplitude of the previous cycle, the index position of the current frequency cross-gear is marked, and the frequency cross-gear recognition result is generated.

[0051] The current response reordering module obtains the change information of the current frequency range based on the frequency cross-range identification result. By comparing the current current response rise rate, the direction of the operating frequency change and the current waveform of the previous cycle, it determines whether the time series of the sampling points needs to be adjusted. Based on the judgment result, the response order is rearranged according to the current frequency range of the inverter, the load state and the current characteristics to generate the current response reordering result.

[0052] The dynamic interference blocking module obtains the voltage and current sampling point sequence after the current response rearrangement result is reordered, extracts the main frequency component of each group of sampling values, calculates the synchronization rate of adjacent sampling points, and judges the frequency difference 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, the sampling point is determined to be the location of the interference signal, the interference channel of the target sampling point is cut off, and it is removed from the sampling sequence to generate the signal interference isolation result.

[0053] Based on the signal interference isolation results, the operation parameter output module obtains the power, peak and average values ​​of current and voltage at the uninterrupted voltage and current sampling points within the cycle, and summarizes the voltage and current status of all cycles according to the time axis. It then outputs the power, frequency and current data of each cycle and generates a set of cycle operation status parameters, which serves as the output basis for the testing phase and is used for subsequent analysis, debugging and system evaluation.

[0054] The sampling point delay correction results include the expected trigger angle, time deviation, and correction timestamp. The frequency cross-gear identification results specifically include the gear switching index, frequency jump amplitude, and reversal indicator. The current response rearrangement results include the sampling order adjustment table, current feature mapping, and frequency gear correspondence. The signal interference isolation results specifically refer to the interference point location, frequency difference marker, and channel shielding status. The set of periodic operation status parameters includes the periodic power index, frequency fluctuation information, and current statistical characteristics.

[0055] Please see Figure 2 The sampling point calibration module includes:

[0056] The voltage sampling and waveform processing submodule acquires the voltage amplitude of the high-voltage and low-voltage side voltage sampling points during the operating cycle of the high- and low-voltage frequency converters, maps them to trigonometric function curves, and uses the formula:

[0057] ;

[0058] Calculate the angle of voltage amplitude change ;

[0059] in, This represents the voltage amplitude on the high-voltage side, measured in volts (V). This represents the voltage amplitude on the low-voltage side, measured in volts (V). This represents the sampling time on the high-voltage side, in seconds (s). This represents the sampling time on the low-voltage side, in seconds (s).

[0060] First, the voltage amplitudes on the high-voltage and low-voltage sides need to be obtained. This process involves using a voltage sampling device to convert the two voltage signals into digital signals for subsequent processing. In practical applications, for example, for a device system with a high-voltage side of 220V and a low-voltage side of 110V, the sampling module can obtain the voltage amplitude values. Next, by mapping these voltage amplitudes to trigonometric function curves, the variation pattern of the voltage amplitude can be obtained. Assuming that at a certain moment, the high-voltage side voltage amplitude is 200V and the low-voltage side voltage amplitude is 180V, according to the formula, trigonometric function formulas can be used to map them and obtain the trajectory of the voltage amplitude variation. Then, using these curve data, the angle of change of the voltage amplitude is calculated. The formula is as follows:

[0061] This formula is used to calculate the angle of change of voltage amplitude over time. Its core is to measure the steepness of the voltage waveform change by using the ratio between the voltage change and the time change.

[0062] Let the high voltage amplitude Low voltage amplitude High-voltage side sampling time Low-pressure side sampling time Substituting into the formula, we get: Ultimately, the voltage amplitude change angle was found to be 89.4°, which provided basic data for subsequent waveform trend analysis.

[0063] The waveform change trend judgment submodule determines the current waveform change trend, including rising or falling segments, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the current waveform change trend, it calculates the desired sampling point and generates the waveform change trend.

[0064] Based on the calculated voltage amplitude change angle (89.4°), the next step is to determine the current waveform's trend. The voltage amplitude change angle reflects the degree of change in voltage amplitude over time. When the voltage amplitude change angle is very large, it indicates a drastic change in the voltage waveform. In this case, if the angle is close to 90°, it can be inferred that the current waveform is in a phase of drastic change, usually a sharp transition within an upward or downward phase. 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 inferred that the waveform is currently in an upward phase because the voltage amplitude change is very large and the angle is close to 90°, meaning the waveform change is quite drastic. Similarly, if the voltage amplitude decreases from 200V to 180V, and the voltage amplitude change angle is 89.4°, then it can be determined that the waveform is in a sharp downward phase. In this way, the trend of the voltage waveform can be determined, and the location of the desired sampling point can be estimated. Assuming the peak voltage of the previous cycle was 220V, and the current voltage amplitude is trending downwards, the desired sampling point location will be calculated in the lower half of the declining waveform, thus ensuring a reasonable distribution of voltage sampling points. This method allows us to obtain the waveform trend, which can then be used for subsequent sampling point correction operations.

[0065] The sampling point correction submodule calculates the time delay between the desired sampling point and the currently set sampling point based on the waveform change trend. If the delay exceeds the preset time threshold, the sampling point trigger time of the current period is corrected, and the sampling point correction result is generated.

[0066] The time delay between the desired sampling point and the currently set sampling point is calculated. This time delay is determined by comparing the deviation between the set sampling point position and the actual waveform change trend. Assuming the currently set sampling point is T=1.5s, and the desired sampling point calculated based on the waveform change trend is T=1.7s, then the time delay between the two is 0.2s. If this time delay exceeds a preset time threshold, correction is necessary. The set time threshold is 0.1s; since the 0.2s delay exceeds the threshold, the sampling point trigger time of the current cycle needs to be corrected. This correction adjusts the sampling point trigger time to be as close as possible to the desired sampling point, ensuring the accuracy of the voltage sampling point. Finally, the correction result generates a sampling point correction result, providing a more accurate time point for subsequent data acquisition and processing.

[0067] Please see Figure 3 The frequency cross-gear recognition module includes:

[0068] The frequency calculation submodule, based on the sampling point delay correction results, extracts the timestamp and corresponding frequency change information of each sampling point within the current period, and calls the current values ​​of multiple consecutive sampling points and adjacent sampling points in the current period, using the formula: ;

[0069] Calculate the operating frequency of the frequency converter in the current cycle. and current rise rate ;

[0070] in, Indicates the first Frequency values ​​of each sampling point This indicates the total number of sampling points in the current period. Indicates the first Current values ​​at each sampling point Indicates the first Current values ​​at each sampling point Indicates the first The timestamp corresponding to each sampling point Indicates the first The timestamp corresponding to each sampling point Indicates the first The absolute value of the current rise rate within the sampling interval.

[0071] First, we need to obtain the sampling time series for the current period. Corresponding frequency sampling sequence and current sampling value sequence The formula for calculating the frequency mean ;

[0072] For example, in actual execution, the frequency values ​​of the 100 sampling points within the current period are summed one by one. Let the frequency values ​​be 48.1, 48.3, 48.6…50.2Hz, with a total sum of 4940Hz. Then: ;

[0073] This represents the average operating frequency within the current period. Indicates the number of sampling points. Indicates the first The calculation logic of this formula is as follows: sum all the sampled frequency values ​​linearly and normalize them by the number of sampling points to quantify the operating frequency level of the frequency converter in a complete cycle.

[0074] The rate of rise of the current was then calculated using the formula:

[0075] ;

[0076] In the continuous sampling points of the current cycle, the change between two adjacent current values ​​is extracted one by one, and the ratio is calculated with the sampling time interval to reflect the degree of current change per unit time. Simultaneously, by taking the absolute value, the absolute intensity of the rise rate is preserved to avoid directional influences, and all... Each segment is averaged.

[0077] To illustrate with a numerical example, if the sampling time is every 10ms, that is... Given that the first five current values ​​are 10.0A, 10.3A, 10.6A, 11.0A, and 11.4A, then: .

[0078] Then average the above results: This value represents the average rate of change of current per unit time within the current cycle. The larger the value, the more intense the current response. The result shows that the current cycle frequency is 49.4 Hz and the current rise rate is 35 A / s, thus generating the current cycle frequency and current rise rate.

[0079] The cross-gear status judgment submodule extracts the average frequency value and current rise rate information of the previous cycle based on the inverter's operating frequency and current rise rate in the current cycle. It compares the frequency change amplitude of the current cycle with twice the average frequency of the previous cycle and determines whether the current rise rate direction is reversed. It then filters the sampling cycles that meet the two conditions to obtain the frequency cross-gear trigger status.

[0080] After retrieving the current cycle frequency and current rise rate, it is necessary to extract the average frequency value of the previous cycle. This operation is the same as in paragraph 1, which involves summing the frequency values ​​from the previous period and dividing by the number of sampling points. Assuming the frequency data from the previous period was from 45.5Hz to 46.5Hz, the sum is 4600Hz, and the number of sampling points is 100, then... ;

[0081] Next, calculate the magnitude of the change in the current cycle frequency. Assuming the current cycle frequency has a maximum value of 53.0 Hz and a minimum value of 47.0 Hz, then:

[0082] ;

[0083] To determine whether the current cycle frequency change exceeds twice the average frequency of the previous cycle, the comparison condition is set as follows:

[0084] ;

[0085] Current period frequency variation amplitude Less than 92.0Hz, which meets condition 1, that is, it does not exceed twice the reference frequency range;

[0086] To further refine the judgment of the frequency change amplitude, a ratio-based calculation method is adopted. ;

[0087] This indicates that the current frequency change is 13.04% of the average frequency of the previous cycle, which is greater than the 10% threshold, and therefore meets the conditions for a frequency change.

[0088] The direction of the current rise rate also needs to be checked. If the current starts at 15A and ends at 12A in the current cycle, the current direction has reversed; while in the previous cycle, the current increased from 10A to 12.5A, and the direction was positive. This can be done by comparing the signs of the current change rate. ;

[0089] in, These represent the starting and ending current values ​​of the current cycle, respectively, in amperes (A). These represent the start and end times of the current cycle, respectively, in seconds; These represent the starting and ending current values ​​of the previous cycle, respectively, in amperes (A). These represent the start and end times of the previous cycle, respectively, in seconds.

[0090] This formula calculates the sign change of the current change rate between the current cycle and the previous cycle. If the signs are opposite (i.e., one is positive and the other is negative), the direction of the current rise rate is reversed. Once the condition is met, the current cycle is marked as the cross-gear trigger cycle, and the frequency cross-gear trigger state is obtained.

[0091] The index position calibration submodule locates the position of the frequency cross-gap trigger state in the current period sampling sequence, calculates the rate of change and offset of the current sampling point in the frequency change process based on the frequency change amplitude value of the previous period, maps the index number of the sampling point, obtains the starting position of the change characteristic, and generates the frequency cross-gap recognition result.

[0092] After invoking the frequency cross-rate trigger state, its specific position in the current period's sampling sequence needs to be further determined. First, the frequency change amplitude of the previous period is extracted. Next, the location of the abrupt change in the current cycle frequency is determined. Assuming the current cycle frequency abruptly changes from 48.0Hz to 53.0Hz, the frequency increment is calculated between the 60th and 80th sampling points, with the increment being... ;

[0093] Therefore, the frequency increment for each sampling point is 0.25 Hz;

[0094] Next, by proportionalizing the relative increment with the amplitude of the previous period, assuming the frequency of the 65th point is 49.5Hz and the increment is 1.5Hz, then its relative increment is... ;

[0095] Then, the index position of this point is determined using this ratio. The index position indicates the point where the frequency mutation occurs. By processing the frequency points of all mutation intervals in the current period through this mapping method, the precise calibration of the mutation position is finally completed, and the frequency cross-gap identification result is generated.

[0096] Please see Figure 4 The current response resequencing module includes:

[0097] The frequency change and current comparison sub-mode obtains the change information of the current frequency range based on the frequency cross-range recognition result. By comparing the rise rate of the current current response, the direction of the change of the working frequency and the current waveform of the previous cycle, it compares the rise rate of the current current response with the direction of the change of the working frequency. If the current rise direction matches the frequency change direction, the time series is not adjusted. If they do not match, it analyzes whether the time series of the sampling points needs to be adjusted and generates an adjustment judgment result.

[0098] First, it's necessary to obtain information about the current frequency range. Then, the rate of increase of the current response and the direction of frequency change are extracted and compared with the current waveform information from the previous cycle. Taking a practical example, when the inverter switches from a low-frequency range to a high-frequency range, its frequency changes from 48Hz to 50Hz, and the current increases accordingly. Assume the current rate of increase in the current cycle is 25A / s, the frequency change amplitude is 2Hz, and the frequency change direction is upward. In this case, it's necessary to determine whether the sampling time series needs adjustment by comparing the consistency between the current rate of increase and the direction of frequency change. If the current's upward direction is consistent with the frequency change direction, then no adjustment to the sampling time series is needed. Otherwise, the previous cycle's current waveform data needs to be analyzed to determine if there is an excessively fast current response speed or mismatched current waveform characteristics, and the sampling time series should be adjusted accordingly. For example, if the current waveform was stable in the previous cycle, but suddenly changes drastically in the current cycle, it indicates a mismatch between the current response and frequency change, requiring adjustment. Finally, through these steps, a matching analysis result between current and frequency is generated to determine whether the sampling time series needs adjustment.

[0099] Based on the adjustment judgment result, the response sequence adjustment submodule analyzes the current frequency range and load characteristics according to the inverter's current frequency range, load status and current characteristics, determines the relationship between the current response mode and frequency switching, adjusts the current response sequence according to the obtained information, rearranges the sampling point time series, and generates the current response rearrangement result.

[0100] Based on the current-frequency matching analysis results obtained in the preceding steps, the response sequence is further adjusted according to the inverter's current frequency range, load status, and current characteristics. Assuming the inverter is currently operating at a high frequency range, the load is light, and the current characteristics are relatively stable, the current response sequence can be maintained. However, if the load is heavy, the current characteristics fluctuate, and the frequency transition identification results show drastic frequency changes, the response sequence needs to be readjusted based on the characteristics of the current changes. For example, when the frequency rapidly switches from 50Hz to 60Hz, the current may not respond promptly, resulting in a response lag. In this case, the time series of the sampling points needs to be adjusted. By analyzing the relationship between the current frequency range change and the current characteristics, combined with the real-time changes in the inverter load, the time series of the sampling points is rearranged to ensure a smooth transition in the current response. In this process, the amplitude of the frequency change and the current response speed are key factors. Finally, a current response rearrangement result is generated to ensure that the inverter can respond quickly and adjust the frequency synchronously when the load changes.

[0101] Please see Figure 5 The dynamic interference blocking module includes:

[0102] The main frequency extraction and synchronization calculation submodule obtains the reordered voltage and current sampling point sequence after the current response rearrangement result, extracts the main frequency component of each group of sampling values, and performs a multiplication calculation on adjacent sampling points of current and voltage. and The formula used is: ; Calculate the synchronization rate of adjacent sampling points ;

[0103] in, and These represent the current sampling points. and main frequency, and These represent the voltage sampling points. and The formula is used to measure the synchronization of frequency changes between voltage and current. A low synchronization rate indicates poor synchronization between voltage and current, which may indicate the presence of interference signals.

[0104] The process involves obtaining the voltage and current sampling point sequences after current response rearrangement, extracting the dominant frequency component of each sample value, and calculating the synchronization rate of adjacent sampling points. Specifically, firstly, the current and voltage sampling points are sorted to ensure data consistency along the time axis. Then, methods such as Fourier transform are used to extract the dominant frequency component of each sampling point to obtain the current... and voltage The frequency characteristics. Assume the voltage sequence is... The current sequence is Extract the corresponding frequencies from these four sampling points respectively. and Then, the synchronization rate of adjacent sampling points is calculated, specifically as follows: ;

[0105] For example, suppose in the first and The difference in current frequency between sampling points is Hz, voltage frequency difference is Hz, substitute into the above formula to calculate the synchronization rate, assuming the sum of the frequencies of current and voltage is . Hz and To obtain the synchronization rate ;

[0106] Based on the synchronization rate results, it can be determined that the voltage and current synchronization of the current sampling point is low, and then it can be decided whether further operations are needed, such as adjusting the time series or marking interference signals.

[0107] The interference signal judgment submodule judges the synchronization rate of 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, the sampling point is determined to be the location of the interference signal. The sampling point with interference characteristics is identified and the interference signal judgment result is generated.

[0108] First, the extracted main frequency components need to be analyzed for frequency differences. If, during the analysis, a significant decrease in synchronization rate is found at a certain sampling point, and the frequency difference exceeds the set interference identification threshold, then that sampling point is identified as the source of interference signals. Specifically, an interference identification threshold is set, assuming a threshold value of 0.5Hz. The threshold is determined when the frequency difference between the current main frequency and the voltage main frequency at a certain sampling point is detected. If the threshold is exceeded, the sampling point is marked as an interference signal point. For example, suppose the first... The voltage main frequency of each sampling point is Hz, current main frequency is Hz, then the frequency difference for Due to frequency difference If the frequency exceeds the set interference threshold of 0.5Hz, the sampling point will be identified as an interference signal point, and a cutoff operation will be performed. An interference signal judgment result will be generated, and further decisions will be made to isolate the signal point.

[0109] Based on the interference signal judgment result, the interference signal isolation submodule cuts off the interference channel of the sampling point where the interference signal is located, readjusts the remaining sampling point sequence, and generates the signal interference isolation result.

[0110] First, the sampling point containing the interference signal needs to be located, and then the interference channel needs to be cut off. Specifically, the sampling point marked as the interference signal is removed from the voltage and current data sequence, and its influence is eliminated from the entire sampling sequence. For example, suppose the first... A sampling point has been identified as an interference signal point. The procedure involves deleting the data from this sampling point from the sampled data sequence and readjusting the remaining data to ensure the accuracy of subsequent signal processing. Finally, a signal interference isolation result is generated, providing a clean signal sequence for subsequent data processing and ensuring the stable operation of the system.

[0111] Please see Figure 6 The runtime parameter output module includes:

[0112] The operating status parameter extraction submodule obtains the power of the voltage and current sampling points that are not disturbed within the cycle based on the signal interference isolation results, and extracts the operating status parameters such as the peak value and average value of the current and voltage to obtain voltage and current status data.

[0113] First, select voltage and current sampling points that are not marked as interference within the current sampling period from the output sequence. The sampling point sequence must correspond to the complete time period within the current control cycle of the frequency converter to ensure that the voltage and current data match on the time axis. In practical applications, for example, if a frequency converter is sampled at a frequency of 1kHz, resulting in 1000 sampling points, and 50 interference points are removed, then 950 sets of valid data are retained for subsequent calculations. Next, extract the voltage and current data from each set of sampling points to analyze its power status and state characteristics. Power evaluation is performed based on a single-point multiplication method. Then, identify the voltage and current peak values ​​within the current period. The peak value is determined by taking the largest value in the sampling sequence. Assuming the voltage sequence within a certain period is V, the maximum value of 239V is the peak voltage of that 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 in the above example is V. Process the current data in the same way and extract the peak and average values ​​to generate the operating status parameter values.

[0114] All voltage and current status data are summarized, and the power, frequency and current data for each cycle are output in categories. By organizing the voltage and current data in each cycle, the power, frequency, peak current and voltage, as well as the average current and voltage of each cycle are extracted to generate a set of cycle operation status parameters.

[0115] The voltage and current states for all cycles are summarized according to the time axis. First, the peak voltage, average voltage, peak current, and average current calculated for each cycle are bound to the timestamps of the corresponding cycles and arranged in chronological order to form a complete cycle sequence data group. Then, each group of data is classified by cycle, numbered, and summarized, and a cycle operation parameter record containing cycle number, power, frequency, and current value is output. A typical example is: a monitoring window records a total of 10 cycles. The sampling data for each cycle has been processed. The parameters corresponding to each cycle are sorted and output according to cycle number 1 to 10. If the power sampling value fluctuates abnormally in cycle 5, the parameter for that cycle will be marked separately in the summary table. In addition, the summary results must record the correspondence between the timestamp and the parameter. After all cycle operation parameters are classified and sorted according to the time axis, they are summarized and output in a unified manner to form a set of cycle operation status parameters.

[0116] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A high- and low-voltage frequency converter testing system, characterized in that, The system includes: The sampling point calibration module acquires the voltage amplitude of the voltage sampling points on the high-voltage side and low-voltage side during the working cycle of the high- and low-voltage frequency converter, fits the trigonometric function curve, calculates the changing angle to determine the waveform trend, corrects the sampling trigger time, and generates the sampling point delay correction result. Based on the sampling point delay correction result, the frequency cross-gap identification module calculates the operating frequency and current rise rate, determines the frequency cross-gap status and calibrates the cross-gap index, and generates the frequency cross-gap identification result. The current response reordering module obtains the change information of the current frequency range based on the frequency cross-range identification result, compares the current current response with the frequency change trend, rearranges the sampling order, and generates the current response reordering result. The dynamic interference blocking module obtains the voltage and current sampling point sequence after the current response rearrangement result is reordered, calculates the synchronization rate and determines whether the frequency difference exceeds the limit, identifies and removes interference sampling points, and generates signal interference isolation results. Based on the signal interference isolation results, the operation parameter output module classifies and outputs the power, frequency and current data for each cycle and summarizes them by cycle to generate a set of cycle operation status parameters. The sampling point delay correction result includes the expected trigger angle, time deviation, and correction timestamp. The frequency cross-gear identification result specifically includes the gear switching index, frequency jump amplitude, and reversal identifier. 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 location, frequency difference marker, and channel shielding status. The set of periodic operation status parameters includes the periodic power index, frequency fluctuation information, and current statistical characteristics.

2. The high and low voltage frequency converter testing system according to claim 1, characterized in that, The sampling point calibration module includes: The voltage sampling and waveform processing submodule acquires the voltage amplitude of the high-voltage and low-voltage side voltage sampling points during the operating cycle of the high- and low-voltage frequency converters, maps them to trigonometric function curves, and uses the formula: ; Calculate the angle of voltage amplitude change ; in, Represents the voltage amplitude on the high-voltage side. Represents the voltage amplitude on the low-voltage side. Represents the sampling time on the high-voltage side. This represents the sampling time on the low-pressure side; The waveform change trend judgment submodule determines the current waveform change trend, including rising or falling segments, based on the voltage amplitude change angle. By comparing the peak voltage of the previous cycle with the current waveform change trend, it calculates the desired sampling point and generates the waveform change trend. The sampling point correction submodule calculates the time delay between the desired sampling point and the currently set sampling point based on the waveform change trend. If the delay exceeds a preset time threshold, the sampling point trigger time of the current period is corrected, and a sampling point correction result is generated.

3. The high and low voltage frequency converter testing system according to claim 2, characterized in that, The frequency cross-gap recognition module includes: Based on the sampling point delay correction result, the frequency calculation submodule extracts the timestamp and corresponding frequency change information of each sampling point in the current cycle, calls the current values ​​of multiple consecutive sampling points and adjacent sampling points in the current cycle, and calculates the operating frequency and current rise rate of the inverter in the current cycle. The cross-gear state judgment submodule extracts the average frequency value and current rise rate information of the previous cycle based on the inverter's operating frequency and current rise rate in the current cycle, compares the frequency change amplitude of the current cycle with twice the average frequency of the previous cycle, and determines whether the current rise rate direction is reversed. It then filters the sampling cycles that meet the two conditions to obtain the frequency cross-gear trigger state. The index position calibration submodule locates the position of the frequency cross-gap trigger state in the current period sampling sequence, calculates the rate of change and offset of the current sampling point in the frequency change process based on the frequency change amplitude value of the previous period, maps the index number of the sampling point, obtains the starting position of the change characteristic, and generates the frequency cross-gap identification result.

4. The high and low voltage frequency converter testing system according to claim 3, characterized in that, The current response reordering module includes: The frequency change and current comparison sub-module obtains the change information of the current frequency level based on the frequency cross-level identification result. By comparing the rise rate of the current current response, the direction of change of the working frequency and the current waveform of the previous cycle, it compares the rise rate of the current current response with the direction of change of the working frequency. If the current rise direction matches the frequency change direction, the time series is not adjusted. If they do not match, it analyzes whether the time series of the sampling points needs to be adjusted and generates an adjustment judgment result. The response sequence adjustment submodule, based on the adjustment judgment result, analyzes the current frequency range and load characteristics according to the inverter's current frequency range, load status and current characteristics, determines the relationship between the current response mode and frequency switching, adjusts the current response sequence according to the acquired information, rearranges the sampling point time series, and generates the current response rearrangement result.

5. The high and low voltage frequency converter testing system according to claim 4, characterized in that, The dynamic interference blocking module includes: The main frequency extraction and synchronization calculation submodule obtains the reordered voltage and current sampling point sequence after the current response rearrangement result, extracts the main frequency component of each group of sampling values, and calculates the main frequency component for adjacent sampling points of current and voltage. and The formula used is: ； Calculate the synchronization rate of adjacent sampling points ; in, and These represent the main frequencies of the first current sampling point j and the adjacent second current sampling point j+1, respectively. and These represent the main frequencies of the first voltage sampling point j and the second voltage sampling point j+1, respectively. The interference signal judgment submodule 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, the sampling point is determined to be the location of the interference signal. The sampling point with interference characteristics is identified and the interference signal judgment result is generated. Based on the interference signal judgment result, the interference signal isolation submodule cuts off the interference channel of the sampling point where the interference signal is located, readjusts the remaining sampling point sequence, and generates a signal interference isolation result.

6. The high and low voltage frequency converter testing system according to claim 5, characterized in that, The operating parameter output module includes: Based on the signal interference isolation results, the operating status parameter extraction submodule obtains the power of the voltage and current sampling points that are not interfered with within the period, and extracts the peak and average operating status parameters of the current and voltage to obtain voltage and current status data. All voltage and current state data are summarized, and the power, frequency, and current data for each cycle are output in categories. By organizing the voltage and current data in each cycle, the power, frequency, peak current and voltage, as well as the average current and voltage of each cycle are extracted to generate a set of cycle operation state parameters.

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