A variable frequency drive power section self-identification method

Abstract

The application relates to the technical field of frequency converter control, and discloses a frequency converter power section self-identification method, which comprises the following steps: obtaining operation state data, generating operation characteristic data containing frequency change state data, state fluctuation characteristics and load response change characteristics; establishing a corresponding relationship between starting working conditions, stable operation working conditions, load change working conditions and power characteristic generation processes, respectively generating starting power change characteristics, stable operation power characteristics and load response power characteristics; complementarily correcting the three types of power characteristics, generating a comprehensive power characteristic set, and matching the comprehensive power characteristic set with a preset power section characteristic set to determine a target power section; and configuring corresponding control parameters according to the target power section to adjust the operation state of the frequency converter. The application establishes an association relationship between different operation working conditions and power characteristic generation processes, so that different operation working conditions correspond to different power representation modes, and the accuracy of power section identification under special working conditions is improved.

Description

Technical Field

[0001] This invention relates to the field of frequency converter control technology, and in particular to a method for self-identification of power range of frequency converters. Background Technology

[0002] With the development of industrial automation control technology, frequency converters are widely used in motor drives and industrial control. To ensure the stable operation of frequency converters of different specifications, it is usually necessary to configure corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters according to the power range of the frequency converter. Therefore, accurately identifying the power range of the frequency converter is an important foundation for achieving reasonable configuration of operating parameters.

[0003] In existing technologies, inverter power range identification typically relies on analyzing operating data such as output current and output power, and uses a unified identification method to determine the power range. However, during actual operation, inverters usually experience special conditions such as startup, stable operation, and load variation. The startup condition corresponds to a phase of rapid output frequency change, the stable operation condition corresponds to a phase of relatively stable output, and the load variation condition corresponds to a phase where external load changes cause fluctuations in output power and torque feedback. The operating data exhibit different characteristics under different conditions.

[0004] The existing technology has at least the following technical problems: the existing power segment identification method does not establish a corresponding power characterization method for different operating conditions. Instead, it uses the operating status data of different operating stages to participate in the power segment identification. This leads to mutual interference between different operating characteristics under special operating conditions, making it difficult to accurately reflect the actual power change law, thereby reducing the accuracy of power segment identification. Summary of the Invention

[0005] To overcome the above shortcomings, this invention provides a power segment self-identification method for frequency converters, aiming to improve the problem that existing technologies are unable to accurately reflect the actual power change pattern, thereby reducing the accuracy of power segment identification.

[0006] This invention provides the following technical solution: a method for self-identifying the power range of a frequency converter, comprising the following steps: S1. Acquire the operating status data during the operation of the frequency converter, and generate operating feature data based on the operating status data. The operating feature data includes frequency change status data, status fluctuation characteristics, and load response change characteristics. S2. Based on the frequency change status data, status fluctuation characteristics and load response change characteristics in the operating characteristic data, perform stage correlation analysis on the inverter operation process, determine the start-up condition, stable operation condition and load change condition, and establish the correlation between different operating conditions and the power characteristic generation process. S3. Based on the operating status data corresponding to the startup condition, stable operation condition and load change condition, independently analyze the changes in operating status under different operating conditions, and generate startup power change characteristics, stable operation power characteristics and load response power characteristics respectively. S4. Based on the complementary relationship between the startup power change characteristics, stable operation power characteristics, and load response power characteristics, feature correction is performed to generate a comprehensive power feature set, and the comprehensive power feature set is matched with a preset power segment feature set to determine the target power segment. S5. Configure corresponding control parameters according to the target power range, and adjust the inverter operating status using the control parameters.

[0007] Preferably, in step S1, the step of acquiring the operating status data during the operation of the frequency converter includes: Collect output current data, output voltage data, output frequency data, and torque feedback data during the operation of the frequency converter; Frequency change status data is generated based on the changes in output frequency data between adjacent sampling times; the output current data, output voltage data, output frequency data, and torque feedback data are correlated to generate the operating status data.

[0008] Preferably, in step S1, the step of generating operational feature data based on the operational status data includes: Based on the changes in output current data and torque feedback data between adjacent sampling times, state fluctuation characteristics are generated; Based on the correspondence between the torque feedback data change process and the output current data change process, load response change characteristics are generated; The frequency change status data, status fluctuation characteristics, and load response change characteristics are correlated with the operating status data to generate the operating characteristic data.

[0009] Preferably, in step S2, the steps of determining the startup condition, stable operation condition, and load change condition include: The output frequency change stage is determined based on the frequency change status data. The stable operating state stage is determined based on the aforementioned state fluctuation characteristics; Determine the load change stage based on the load response change characteristics; Based on the correlation between the output frequency change stage, the stable operation stage, and the load change stage, the corresponding startup condition, stable operation condition, and load change condition are determined.

[0010] Preferably, in step S2, the steps concerning the association between the generation processes include: Acquire operating status data corresponding to startup, stable operation, and load change conditions; Based on the characteristics of operating state changes corresponding to different operating conditions, determine the corresponding power characteristic generation method; Establish the correspondence between startup conditions and startup power variation characteristics, stable operation conditions and stable operation power characteristics, and load variation conditions and load response power characteristics.

[0011] Preferably, in step S3, the step of generating the startup power change characteristics includes: Obtain the running status data corresponding to the startup condition; Based on the correspondence between the output frequency change process and the output power change process under startup conditions, the power change process during the startup phase is determined. The startup power change characteristics are generated based on the power change process during the startup phase.

[0012] Preferably, in step S3, the step of generating stable operating power characteristics and load response power characteristics includes: Obtain the operating status data corresponding to the stable operating condition, determine the output power change under the stable operating condition based on the output current data and output voltage data under the stable operating condition, and generate the stable operating power characteristics. Obtain the operating status data corresponding to the load change conditions, and generate the load response power characteristics based on the correlation between the torque feedback data change process and the output power change process during the load change process.

[0013] Preferably, in step S4, the step of performing feature correction based on the complementary relationship between the startup power variation characteristics, stable operating power characteristics, and load response power characteristics includes: Acquire startup power variation characteristics, stable operating power characteristics, and load response power characteristics; Analyze the correlation between power characteristics corresponding to different operating conditions; Based on the complementary relationship between the power characteristics corresponding to different operating conditions, the starting power change characteristics, stable operating power characteristics, and load response power characteristics are corrected to generate the comprehensive power characteristic set.

[0014] Preferably, in step S4, the step of determining the target power range includes: Obtain the power feature set corresponding to different preset power ranges; The comprehensive power feature set is matched with the power feature sets corresponding to different power segments respectively; The target power segment corresponding to the comprehensive power feature set is determined based on the matching results.

[0015] Preferably, in step S5, the step of configuring the corresponding control parameters according to the target power range includes: Determine the corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters based on the target power range; The current limiting parameters, torque control parameters, and acceleration / deceleration control parameters are associated with the inverter's operating status. Configure the inverter operating parameters based on the association results.

[0016] The present invention has the following beneficial effects: 1. This invention generates operational characteristic data that includes frequency change state data, state fluctuation characteristics, and load response change characteristics, and establishes a correlation between different operating conditions and the power characteristic generation process. This allows startup conditions, stable operating conditions, and load change conditions to correspond to different power characterization methods, avoiding the mixing of operational data from different operating stages in power segment identification and improving the accuracy of power segment identification under special operating conditions.

[0017] 2. This invention generates startup power change characteristics, stable operation power characteristics, and load response power characteristics for startup conditions, stable operation conditions, and load change conditions, respectively, so that the power change patterns of different operating stages can independently participate in power segment identification, reducing the identification deviation caused by the mutual influence of data from different operating stages.

[0018] 3. This invention generates a comprehensive power feature set by complementary correction of the starting power change characteristics, stable operation power characteristics, and load response power characteristics. The target power segment is determined by combining the comprehensive power feature set with the preset power segment feature set, so that the power segment identification result corresponds with the control parameter configuration, thereby improving the stability of power segment identification. Attached Figure Description

[0019] Figure 1 This is a flowchart of a frequency converter power segment self-identification method proposed in this invention; Figure 2 This is a flowchart of the operation status data acquisition and operation feature data generation proposed in this invention; Figure 3 This is a flowchart illustrating the determination of startup conditions, stable operation conditions, and load change conditions proposed in this invention. Figure 4 This is a schematic diagram illustrating the correlation between different operating conditions and the power characteristic generation process proposed in this invention; Figure 5 This is a flowchart of the multi-condition power characteristic complementary correction and target power segment matching proposed in this invention. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Reference Figure 1 Example 1: This example provides a method for automatic identification of power segments in a frequency converter, applicable to the automatic identification of power segments during the operation of frequency converter-driven motors, fans, pumps, or conveying equipment. The method is executed by the frequency converter controller or a processing device communicatively connected to the frequency converter. The processing device can acquire output current, output voltage, output frequency, and torque feedback data during the frequency converter's operation, and complete the division of operating conditions, power characteristic generation, power segment matching, and control parameter configuration based on the data. The method includes the following steps: S1. Acquire the operating status data during the operation of the frequency converter, and generate operating characteristic data based on the operating status data. The operating characteristic data includes frequency change status data, status fluctuation characteristics, and load response change characteristics. Preferably, in step S1, the step of acquiring the operating status data during the operation of the frequency converter includes: Collect output current data, output voltage data, output frequency data, and torque feedback data during the operation of the frequency converter; Frequency change status data is generated based on the changes in output frequency data between adjacent sampling times; output current data, output voltage data, output frequency data, and torque feedback data are correlated to generate operating status data.

[0022] Specifically, the frequency converter controller synchronously collects output current, output voltage, output frequency, and torque feedback according to a preset sampling period. Each sampled data point is marked with a corresponding sampling time identifier, and the data are arranged in the sampling order to form an operating status unit. The operating status unit is represented as follows: ; in, Indicates the first The running status unit corresponding to each sampling time; This indicates the output current data; This indicates the output voltage data; This indicates the output frequency data; This represents torque feedback data. Each operating state unit is arranged in the order of its sampling time to form an operating state data sequence, ensuring that different types of operating parameters maintain the same time reference.

[0023] Subsequently, frequency change status data is generated based on the changes in output frequency data between adjacent sampling times, and the output frequency change is expressed as: ; in, Indicates the first The change in output frequency at each sampling time; This represents the output frequency data at the current sampling time. This represents the output frequency data at the previous sampling time. The frequency change status data is determined based on the changes in output frequency over multiple consecutive sampling periods, and the corresponding time intervals are recorded to provide input data for subsequent operational analysis.

[0024] After generating frequency change status data, status fluctuation characteristics and load response change characteristics are further generated based on the operating status data. The status fluctuation characteristics are determined based on the changes in output current data, output voltage data, and torque feedback data within a continuous sampling period, and are used to characterize the degree of change in operating status. The load response change characteristics are generated based on the correspondence between the torque feedback change process and the output current change process, and are used to characterize the response of the inverter's output status during load changes. Both types of characteristics are correlated with the corresponding sampling time and, together with the frequency change status data, constitute the operating characteristic data.

[0025] Finally, the operating status data, frequency change status data, status fluctuation characteristics, and load response change characteristics are organized according to a unified time series to form corresponding operating characteristic data. This ensures that various operating parameters and their derived characteristics maintain a consistent data organization method, providing a unified data input for subsequent correlation analysis of operating phases and generation of power characteristics under different operating conditions. Through the above processing, the correspondence between operating status data and operating characteristic data is established, providing a complete data foundation for subsequent operating condition identification and power segment identification.

[0026] Preferably, in step S1, the step of generating operational feature data based on operational status data includes: Based on the changes in output current data and torque feedback data between adjacent sampling times, state fluctuation characteristics are generated; Based on the correspondence between the torque feedback data change process and the output current data change process, load response change characteristics are generated; By associating frequency change status data, status fluctuation characteristics, and load response change characteristics with operating status data, operating characteristic data is generated.

[0027] Specifically, after acquiring the operating status data, a state fluctuation characteristic is first generated based on the changes in output current and torque feedback data between consecutive sampling times. To reflect the degree of change in operating status, the changes in output current and torque feedback at adjacent sampling times are calculated, and a state fluctuation value is constructed. The calculation method is as follows: ; in, Indicates the first The state fluctuation value corresponding to each sampling time; This represents the output current data at the current sampling moment; This represents the output current data at the previous sampling time. This represents the torque feedback data at the current sampling moment; This represents the torque feedback data at the previous sampling time. Indicates the weighting of output current changes; This indicates the weighting of torque feedback changes. In this scheme, The preferred value is 0.6. The optimal value is 0.4, allowing changes in output current and torque feedback to jointly participate in the generation of state fluctuation characteristics. When the state fluctuation value continuously increases over multiple consecutive sampling periods, the corresponding operating state is marked as an enhanced fluctuation state; when the state fluctuation value remains within a preset range, the corresponding operating state remains stable.

[0028] Subsequently, load response variation characteristics are generated based on the correspondence between the torque feedback data change process and the output current data change process. Specifically, the output current change sequence and torque feedback change sequence within multiple consecutive sampling periods are used as the analysis objects, and the degree of consistency between their responses is calculated. The calculation method is expressed as follows: ; in, Indicates the first Load response change characteristics at each sampling time; This represents the change in torque feedback between adjacent sampling times; This indicates the change in output current between adjacent sampling times; This represents a correction parameter to prevent the denominator from being zero. In this scheme, The preferred value is 0.001. When the load changes, the torque feedback data and the output current data change synchronously, and their correspondence is used to reflect the response of the inverter's output state during the load change process.

[0029] After generating the state fluctuation characteristics and load response change characteristics, the frequency change state data, state fluctuation characteristics, and load response change characteristics are uniformly organized according to the sampling time and correlated with the operating state data at the corresponding sampling time. Each operating state unit corresponds to a set of frequency change state data, a set of state fluctuation characteristics, and a set of load response change characteristics, forming an operating characteristic data sequence according to the sampling time order. In this scheme, the operating characteristic data is preferably updated using a sliding time window method, with the sliding window length preferably being 16 to 32 sampling periods, to ensure that the operating characteristic data can continuously reflect the change process of the inverter's operating state.

[0030] By using the above method, while maintaining the time consistency of operating status data, we further generate status fluctuation characteristics and load response change characteristics, and combine them with frequency change status data to form operating characteristic data. This enables operating status changes, frequency changes, and load response changes to form a unified data expression, providing a complete data foundation for subsequent operating condition correlation analysis and power characteristic generation under different operating conditions.

[0031] Reference Figure 2 and Figure 3 Furthermore, S2, based on the frequency change status data, status fluctuation characteristics and load response change characteristics in the operating characteristic data, perform stage correlation analysis on the inverter operation process, determine the start-up condition, stable operation condition and load change condition, and establish the correlation between different operating conditions and the power characteristic generation process. Preferably, in step S2, the steps for determining the startup condition, stable operation condition, and load change condition include: Determine the stage of output frequency change based on frequency change status data; Determine the stable operating stage based on the characteristics of state fluctuations; Determine the stage of load change based on load response change characteristics; Based on the correlation between the output frequency change stage, the stable operation stage, and the load change stage, the corresponding startup condition, stable operation condition, and load change condition are determined.

[0032] Preferably, in step S2, the steps for generating the association between processes include: Acquire operating status data corresponding to startup, stable operation, and load change conditions; Based on the characteristics of operating state changes corresponding to different operating conditions, determine the corresponding power characteristic generation method; Establish the correspondence between startup conditions and startup power variation characteristics, stable operation conditions and stable operation power characteristics, and load variation conditions and load response power characteristics.

[0033] Specifically, firstly, the output frequency change stage is determined based on the frequency change status data in the operational characteristic data. The output frequency change is statistically analyzed over multiple consecutive sampling periods, and the average frequency change is calculated as follows: ; in, This indicates the average frequency change within the current analysis window; Indicates the first The change in output frequency corresponding to each sampling period; This indicates the number of sampling periods contained in the analysis window. In this scheme, the preferred analysis window length is 20 sampling periods. When the frequency change exceeds a preset threshold, the current operating phase is determined to be an output frequency change phase; when... If the frequency remains below the frequency variation threshold, the output frequency is considered to have entered a stable state. In this scheme, the frequency variation threshold is preferably 2% of the rated output frequency.

[0034] Subsequently, the stable operating state is determined based on the state fluctuation characteristics. The average value of the state fluctuation characteristics is calculated within the analysis window and compared with a preset state fluctuation threshold. When the state fluctuation characteristics are all less than the state fluctuation threshold for multiple consecutive sampling periods, the current operating state is determined to be in a stable operating state; when the state fluctuation characteristics continuously exceed the state fluctuation threshold, the operating state is considered to have changed. In this scheme, the state fluctuation threshold is preferably 15% of the maximum value of the state fluctuation characteristics, and the consecutive determination period is preferably 5 sampling periods to reduce the impact of instantaneous fluctuations on the stage determination results.

[0035] Furthermore, the load change stage is determined based on the load response change characteristics. When the load response change characteristics continuously change over multiple consecutive sampling periods and the change amplitude exceeds a preset response threshold, the load is determined to have changed, and the corresponding operating stage is identified as the load change stage. When the load response change characteristics remain within the preset response range, the original operating stage is maintained. In this scheme, the response threshold is preferably 20% of the average value of the load response change characteristics, used to distinguish between normal operation fluctuations and actual load change processes.

[0036] After determining the three operational phases, a correlation analysis is performed on the output frequency change phase, the stable operation phase, and the load change phase. When the output frequency change phase persists, the corresponding operating condition is identified as the startup phase. When the stable operation phase persists and no load change phase is detected, the corresponding operating condition is identified as the stable operation phase. When a load change phase is detected, regardless of whether the output frequency remains stable, the corresponding operating condition is preferentially identified as the load change phase. Subsequently, operating status data within the corresponding time interval is extracted based on the determined operating conditions, and a correspondence is established between the operating conditions and the power feature generation process. Specifically, the startup phase corresponds to the startup power change feature generation process, the stable operation phase corresponds to the stable operation power feature generation process, and the load change phase corresponds to the load response power feature generation process. This ensures that different operating conditions only call the corresponding power feature generation method, avoiding data from different operating phases from participating in the same power feature calculation.

[0037] Through the above-mentioned stage correlation analysis process, the correspondence between operating characteristic data and operating conditions is established, and the correlation between different operating conditions and power characteristic generation process is further established, so that subsequent power characteristic generation can be executed according to the corresponding operating conditions, providing an operating basis for the independent generation of power characteristics in different operating stages.

[0038] Reference Figure 4 Furthermore, S3, based on the operating status data corresponding to the startup condition, stable operation condition and load change condition, independently analyze the changes in operating status under different operating conditions, and generate startup power change characteristics, stable operation power characteristics and load response power characteristics respectively. Preferably, in step S3, the step of generating the startup power change characteristics includes: Obtain the running status data corresponding to the startup condition; Based on the correspondence between the output frequency change process and the output power change process under startup conditions, the power change process during the startup phase is determined. Startup power change characteristics are generated based on the power change process during the startup phase.

[0039] Preferably, in step S3, the steps of generating stable operating power characteristics and load response power characteristics include: Obtain the operating status data corresponding to the stable operating condition, determine the output power change under the stable operating condition based on the output current data and output voltage data under the stable operating condition, and generate stable operating power characteristics; Obtain operating status data corresponding to load change conditions, and generate load response power characteristics based on the correlation between torque feedback data change process and output power change process during load change.

[0040] Specifically, firstly, the starting power variation characteristics are generated based on the operating status data corresponding to the starting condition. For each sampling moment within the time interval corresponding to the starting condition, the output power is calculated based on the output voltage and output current data. The calculation method is as follows: ;in, Indicates the first Output power corresponding to each sampling time; This indicates the output voltage data; This indicates the output current data.

[0041] Subsequently, a correspondence is established between the output frequency change process and the output power change process during the startup phase, and the power change corresponding to a unit frequency change during the startup phase is calculated. The calculation method is as follows: ; in, Indicates the characteristics of starting power variation; This represents the change in output power between adjacent sampling times; This indicates the change in output frequency between adjacent sampling times; This represents a correction parameter to prevent the denominator from being zero. In this scheme, The optimal value is 0.001. The startup power change characteristics corresponding to each sampling period during the startup phase are arranged in chronological order to form a startup power change sequence, which serves as the power characterization result for the startup condition.

[0042] Furthermore, stable operating power characteristics are generated based on the operating status data corresponding to stable operating conditions. First, the output power at each sampling time during the stable operating phase is calculated, and then the average output power within the analysis window is statistically analyzed. The calculation method is as follows: ; in, This represents the average output power during the stable operation phase. This represents the output power at each sampling time. This indicates the number of sampling points within the analysis window. In this scheme, the preferred analysis window length is 32 sampling periods. Subsequently, stable operating power characteristics are generated based on the output power changes within the continuous analysis window, and the stable operating state within the corresponding time interval is recorded to reflect the power output characteristics of the inverter during the stable operating phase.

[0043] Subsequently, load response power characteristics are generated based on the operating status data corresponding to the load change conditions. The correspondence between the output power change and the torque feedback change between adjacent sampling moments during the load change process is calculated as follows: ; in, Indicates the load response power characteristics; This represents the change in output power between adjacent sampling times; This represents the change in torque feedback between adjacent sampling times; This indicates the correction parameter. In this scheme, The optimal value is 0.001. When the load response power characteristics remain stable over multiple consecutive sampling periods, the statistical results within the corresponding analysis window are used as the load response power characteristics corresponding to the current load change condition.

[0044] After generating the startup power change characteristics, stable operation power characteristics, and load response power characteristics, establish the correspondence between each power characteristic and the corresponding operating condition, and save the operating status data and power characteristic data in the corresponding analysis window to ensure that the three types of power characteristics come from data of different operating conditions and are not cross-calculated or mixed.

[0045] Through the above processing, independent power characteristic analysis is performed on the startup condition, stable operation condition, and load change condition, respectively, generating startup power change characteristics, stable operation power characteristics, and load response power characteristics, so that the power change pattern in different operating stages can be characterized separately, providing corresponding input data for subsequent multi-condition power characteristic correction and target power segment identification.

[0046] Reference Figure 5 Furthermore, S4, based on the complementary relationship between the starting power change characteristics, stable operation power characteristics and load response power characteristics, feature correction is performed to generate a comprehensive power feature set, and the comprehensive power feature set is matched with the preset power segment feature set to determine the target power segment; Preferably, in step S4, the step of performing feature correction based on the complementary relationship between the startup power variation characteristics, the stable operating power characteristics, and the load response power characteristics includes: Acquire startup power variation characteristics, stable operating power characteristics, and load response power characteristics; Analyze the correlation between power characteristics corresponding to different operating conditions; Based on the complementary relationship between the power characteristics corresponding to different operating conditions, the starting power change characteristics, stable operating power characteristics, and load response power characteristics are corrected to generate a comprehensive power characteristic set.

[0047] Preferably, in step S4, the step of determining the target power range includes: Obtain the power feature set corresponding to different preset power ranges; The comprehensive power feature set is matched with the power feature sets corresponding to different power segments; The target power segment corresponding to the comprehensive power feature set is determined based on the matching results.

[0048] Specifically, the startup power variation characteristics, stable operation power characteristics, and load response power characteristics are first acquired and then time-aligned using the same analysis window. Since the three types of power characteristics originate from startup conditions, stable operation conditions, and load variation conditions, respectively, it is first determined whether the corresponding operating conditions for each power characteristic are complete. If the data corresponding to a certain operating condition is insufficient for the preset analysis window length, the power characteristics corresponding to the previous analysis cycle are retained for subsequent correction processes. When all three types of power characteristics meet the analysis conditions, the feature correction process begins.

[0049] Subsequently, the participation weights of each power characteristic are calculated based on the correlation between power characteristics corresponding to different operating conditions, and a comprehensive power characteristic is generated. The calculation method is as follows: ; in, Indicates the overall power characteristics; Indicates the characteristics of starting power variation; Indicates stable operating power characteristics; Indicates the load response power characteristics; , and Let represent the correction weights corresponding to the three types of power characteristics, and satisfy . In this plan, The preferred value is 0.25. The preferred value is 0.45. The preferred value is 0.30. The correction weight can be dynamically adjusted according to the completeness of the data corresponding to the current operating condition. When the data corresponding to a certain operating condition is continuously missing, the corresponding correction weight is reduced, and the weight is redistributed according to the remaining power characteristics, so that the comprehensive power characteristics are always generated by the effective power characteristics.

[0050] After generating the comprehensive power characteristics, the power characteristic sets corresponding to different preset power ranges are obtained. These preset power range characteristic sets are established based on the rated power of different inverter models, with each power range corresponding to a set of standard power characteristic parameters. In this solution, the preset power ranges include multiple power levels such as 0.75kW, 1.5kW, 2.2kW, 4kW, 5.5kW, 7.5kW, 11kW, and 15kW, and each power level stores corresponding standard comprehensive power characteristic data.

[0051] Subsequently, the comprehensive power feature set is matched with the feature sets of each preset power segment, and the matching deviation between the comprehensive power feature set and each power segment is calculated. The calculation method is as follows: ; in, Indicates the comprehensive power characteristics and the first Matching deviation between preset power ranges; Indicates the overall power characteristics; Indicates the first The standard power characteristics are corresponding to each preset power segment. After all preset power segments are matched, the preset power segment with the smallest matching deviation is selected as the target power segment. In this scheme, when the minimum matching deviation remains consistent for three consecutive analysis windows, the corresponding preset power segment is determined as the final target power segment; if the matching results of consecutive analysis windows change, data acquisition continues and the matching process is re-executed to reduce the impact of instantaneous changes in operating status on the power segment determination results.

[0052] Through the above processing, the characteristics of starting power change, stable operation power and load response power are uniformly corrected to generate a comprehensive power feature set. The comprehensive power feature set is then used to match the preset power segment feature set, so that the determination of the target power segment takes into account the power change characteristics corresponding to different operating conditions, and provides the corresponding power segment identification results for subsequent control parameter configuration.

[0053] Furthermore, S5 configures the corresponding control parameters according to the target power range and uses the control parameters to adjust the inverter's operating status; Preferably, in step S5, the step of configuring the corresponding control parameters according to the target power range includes: Determine the corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters based on the target power range; Associate the current limiting parameters, torque control parameters, and acceleration / deceleration control parameters with the inverter's operating status; Configure the inverter operating parameters based on the association results.

[0054] Specifically, firstly, the system queries a pre-established control parameter configuration table based on the target power segment to obtain the corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters. The control parameter configuration table can be stored in the inverter controller or external memory, with each power segment corresponding to a set of preset control parameters. Once the target power segment is determined, the corresponding control parameters are read, and a target control parameter set is generated.

[0055] Subsequently, the current limiting parameters are determined based on the rated output current corresponding to the target power range, and the calculation method is as follows: ;in, Indicates the current limiting parameter; This indicates the rated output current corresponding to the target power range; This represents the current limiting factor. In this scheme, The value is preferably 1.05 to 1.20, and more preferably 1.10, so that the current limit value retains a certain control margin while meeting the normal operation requirements of the frequency converter.

[0056] Furthermore, the torque control parameters are determined based on the rated output torque corresponding to the target power range, and the calculation method is as follows: ; in, Indicates torque control parameters; This indicates the rated output torque corresponding to the target power range; This represents the torque adjustment coefficient. In this scheme, The value is preferably 0.95 to 1.05, more preferably 1.00, so that the configured torque control parameters are consistent with the rated torque corresponding to the target power range.

[0057] After determining the current limiting parameters and torque control parameters, the acceleration time parameters and deceleration time parameters are further determined based on the target power range, and these parameters are combined into a target control parameter set. Preferably, the higher the power range, the greater the corresponding acceleration time, and the corresponding deceleration time is adjusted synchronously to ensure that the inverter's operating state matches the operating requirements corresponding to the target power range. In this scheme, the acceleration time is preferably 2-10s, and the deceleration time is preferably 2-12s. The specific parameters are directly called from the configuration table corresponding to the target power range.

[0058] Subsequently, the target control parameter set is associated with the current inverter operating status and written to the controller parameter area via the inverter communication interface. After the parameter writing is completed, the current inverter feedback parameters are read, and the consistency of the current limiting parameters, torque control parameters, and acceleration / deceleration control parameters is verified. When the read parameters are consistent with the target control parameters, the parameter configuration is completed. If there are inconsistencies, the parameter writing process is re-executed until the control parameter configuration is complete.

[0059] Through the above processing, the corresponding current limiting parameters, torque control parameters and acceleration / deceleration control parameters are automatically configured according to the target power segment. The inverter's operating state is then adjusted using the configured control parameters to maintain a correspondence between the control parameters and the target power segment, thus achieving linkage control between the power segment identification result and the operating parameter configuration process.

[0060] Example 2: This example uses a frequency converter with a rated power of 7.5kW as the implementation object to illustrate the frequency converter power segment self-identification method proposed in this invention.

[0061] After the frequency converter starts, the controller continuously collects output current data, output voltage data, output frequency data, and torque feedback data at a sampling period of 10ms, and assembles them into operating status data in chronological order. Subsequently, based on the continuously sampled data, it generates frequency change status data, status fluctuation characteristics, and load response change characteristics, and completes the construction of operating characteristic data.

[0062] During the startup phase, the output frequency continuously increases. The system determines that the current operating state belongs to the startup condition based on the frequency change status data and extracts the corresponding operating state data to generate startup power change characteristics. When the output frequency remains stable and the status fluctuation characteristics are continuously lower than the preset threshold, the system determines that the current operating state has entered the stable operating state and generates stable operating power characteristics. During operation, when the equipment load changes, the torque feedback data and output power change synchronously. The system determines that it has entered the load change condition based on the load response change characteristics and generates load response power characteristics.

[0063] Subsequently, complementary corrections are performed on the starting power variation characteristics, stable operating power characteristics, and load response power characteristics to generate a comprehensive power characteristic set, which is then matched with a preset power segment characteristic set. When the matching deviation between the comprehensive power characteristics and the characteristic set corresponding to the 7.5kW power segment is minimal, the current target power segment is determined to be 7.5kW, and the corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters are automatically configured to complete the adjustment of the inverter's operating parameters.

[0064] To further illustrate the technical solution of the present invention, a comparison is made with the traditional method of power segment identification based on only a single operating parameter, and the differences are shown in Table 1.

[0065] Source of runtime data Output current or output power (single parameter) Joint analysis of output current, output voltage, output frequency and torque feedback Operating condition analysis method No distinction between operating phases Distinguish between startup conditions, stable operation conditions, and load variation conditions. Power Feature Generation All operational data are used to generate power characteristics. Generate corresponding power characteristics for different operating conditions. Feature processing methods Direct matching of single features Multi-condition power characteristic complementary correction matching Power segment identification criteria Single power characteristics Comprehensive power characteristic set Parameter configuration method Manual or fixed parameter configuration Automatically configure control parameters based on the target power range

[0066] Table 1 compares this scheme with traditional power band identification methods; As shown in Table 1, in the power segment identification process of this embodiment, the inverter operation process is divided into startup condition, stable operation condition and load change condition, and corresponding power characteristics are generated for each condition. Then, a comprehensive power feature set is generated by complementary correction of power features under multiple operating conditions for power segment identification. This avoids data from different operating stages from participating in the same power feature calculation, so that the target power segment can be determined according to the power change under different operating conditions, and the corresponding control parameters are configured according to the identification results.

[0067] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for self-identifying the power range of a frequency converter, characterized in that, Includes the following steps: S1. Acquire the operating status data during the operation of the frequency converter, and generate operating feature data based on the operating status data. The operating feature data includes frequency change status data, status fluctuation characteristics, and load response change characteristics. S2. Based on the frequency change status data, status fluctuation characteristics and load response change characteristics in the operating characteristic data, perform stage correlation analysis on the inverter operation process, determine the start-up condition, stable operation condition and load change condition, and establish the correlation between different operating conditions and the power characteristic generation process. S3. Based on the operating status data corresponding to the startup condition, stable operation condition and load change condition, independently analyze the changes in operating status under different operating conditions, and generate startup power change characteristics, stable operation power characteristics and load response power characteristics respectively. S4. Based on the complementary relationship between the startup power change characteristics, stable operation power characteristics, and load response power characteristics, feature correction is performed to generate a comprehensive power feature set, and the comprehensive power feature set is matched with a preset power segment feature set to determine the target power segment. S5. Configure corresponding control parameters according to the target power range, and adjust the inverter operating status using the control parameters.

2. The inverter power segment self-identification method according to claim 1, characterized in that, In step S1, the step of acquiring the operating status data during the operation of the frequency converter includes: Collect output current data, output voltage data, output frequency data, and torque feedback data during the operation of the frequency converter; Frequency change status data is generated based on the changes in output frequency data between adjacent sampling times; the output current data, output voltage data, output frequency data, and torque feedback data are correlated to generate the operating status data.

3. The inverter power segment self-identification method according to claim 1, characterized in that, In step S1, the step of generating operational feature data based on the operational status data includes: Based on the changes in output current data and torque feedback data between adjacent sampling times, state fluctuation characteristics are generated; Based on the correspondence between the torque feedback data change process and the output current data change process, load response change characteristics are generated; The frequency change status data, status fluctuation characteristics, and load response change characteristics are correlated with the operating status data to generate the operating characteristic data.

4. The inverter power segment self-identification method according to claim 1, characterized in that, In step S2, the steps of determining the startup condition, stable operation condition, and load change condition include: The output frequency change stage is determined based on the frequency change status data. The stable operating state stage is determined based on the aforementioned state fluctuation characteristics; Determine the load change stage based on the load response change characteristics; Based on the correlation between the output frequency change stage, the stable operation stage, and the load change stage, the corresponding startup condition, stable operation condition, and load change condition are determined.

5. The inverter power segment self-identification method according to claim 1, characterized in that, In step S2, the steps concerning the association between the generation processes include: Acquire operating status data corresponding to startup, stable operation, and load change conditions; Based on the characteristics of operating state changes corresponding to different operating conditions, determine the corresponding power characteristic generation method; Establish the correspondence between startup conditions and startup power variation characteristics, stable operation conditions and stable operation power characteristics, and load variation conditions and load response power characteristics.

6. The inverter power segment self-identification method according to claim 1, characterized in that, In step S3, the step of generating the startup power change characteristics includes: Obtain the running status data corresponding to the startup condition; Based on the correspondence between the output frequency change process and the output power change process under startup conditions, the power change process during the startup phase is determined. The startup power change characteristics are generated based on the power change process during the startup phase.

7. The inverter power segment self-identification method according to claim 1, characterized in that, In step S3, the steps of generating stable operating power characteristics and load response power characteristics include: Obtain the operating status data corresponding to the stable operating condition, determine the output power change under the stable operating condition based on the output current data and output voltage data under the stable operating condition, and generate the stable operating power characteristics. Obtain the operating status data corresponding to the load change conditions, and generate the load response power characteristics based on the correlation between the torque feedback data change process and the output power change process during the load change process.

8. The inverter power segment self-identification method according to claim 1, characterized in that, In step S4, the step of performing feature correction based on the complementary relationship between the startup power variation characteristics, stable operating power characteristics, and load response power characteristics includes: Acquire startup power variation characteristics, stable operating power characteristics, and load response power characteristics; Analyze the correlation between power characteristics corresponding to different operating conditions; Based on the complementary relationship between the power characteristics corresponding to different operating conditions, the starting power change characteristics, stable operating power characteristics, and load response power characteristics are corrected to generate the comprehensive power characteristic set.

9. The inverter power segment self-identification method according to claim 1, characterized in that, In step S4, the step of determining the target power range includes: Obtain the power feature set corresponding to different preset power ranges; The comprehensive power feature set is matched with the power feature sets corresponding to different power segments respectively; The target power segment corresponding to the comprehensive power feature set is determined based on the matching results.

10. The inverter power segment self-identification method according to claim 1, characterized in that, In step S5, the step of configuring corresponding control parameters according to the target power range includes: Determine the corresponding current limiting parameters, torque control parameters, and acceleration / deceleration control parameters based on the target power range; The current limiting parameters, torque control parameters, and acceleration / deceleration control parameters are associated with the inverter's operating status. Configure the inverter operating parameters based on the association results.

Images