Motor stator winding fault diagnosis method and device, electronic equipment and storage medium

Abstract

The invention particularly relates to a motor stator winding fault diagnosis method and device, electronic equipment and a storage medium. The method comprises the following steps: acquiring three-phase stator current and three-phase stator voltage of a target asynchronous motor in a normal state; performing phase sequence analysis on the voltage characteristic frequency spectrum component and the current characteristic frequency spectrum component; when the target asynchronous motor is in a normal state, negative sequence admittance is determined through the quantitative relation between the negative sequence current and the negative sequence voltage; the target asynchronous motor is in a fault diagnosis state, and positive and negative sequence transfer admittance is determined according to the negative sequence admittance, the positive and negative sequence current and voltage; and determining a fault diagnosis result of the target asynchronous motor according to the positive and negative sequence transfer admittance and the safety region. The motor stator winding fault diagnosis method has the beneficial effects that high robustness, low calculation complexity and multi-fault type fault diagnosis of motor stator winding fault diagnosis are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor fault diagnosis, and in particular relates to a motor stator winding fault diagnosis method, device, electronic equipment and storage medium. Background Art

[0002] With the increasing demand for power supply reliability, there is a growing desire to detect faults before they occur (relay protection action) and to conduct repairs and troubleshooting in advance. Furthermore, based on the analysis of fault evolution trends, it is hoped that the health and life of the equipment can be estimated to guide planned maintenance.

[0003] Asynchronous motors (primarily squirrel-cage motors) are the largest load in the power grid and account for the highest proportion of electricity consumption. Their importance in industry is undeniable. Prompt diagnosis of early faults, such as stator winding insulation degradation and interturn short circuits, is crucial for preventing downtime. Research on early fault diagnosis for asynchronous motors has gradually been commercialized. However, existing non-invasive fault diagnosis technologies generally suffer from high false positive rates, complex implementation, insufficient real-time performance, and limited diagnostic coverage.

[0004] Existing technologies include Park vector trajectory images and positive and negative sequence component separation for fault identification. However, these technologies have the following drawbacks: (1) The Park vector trajectory is susceptible to load fluctuations or grid harmonic interference, resulting in insufficient stability of the characteristic vector. This method requires the acquisition of a large number of current signals and the generation of images, which has high computational complexity and is difficult to meet the needs of real-time monitoring. In addition, the interference suppression of voltage signals on non-fault factors is not considered, which may lead to misjudgment. (2) Dynamic analysis of over-sequence components and screening of voltage imbalance factors reduce the impact of non-fault interference. However, the inherent negative sequence component needs to be calibrated in advance, which makes it difficult to adapt to changes in motor parameters in practical applications. Only the negative sequence current amplitude is used for judgment, and the fault judgment dimension is single. (3) Weak anti-interference ability, poor robustness to motor parameter changes and dynamic working conditions (such as load fluctuations and grid interference). Summary of the Invention

[0005] The main purpose of the embodiments of the present invention is to propose a motor stator winding fault diagnosis method, device, electronic device and storage medium, which achieve high robustness, low computational complexity and multi-fault category fault diagnosis of the motor stator winding fault.

[0006] One aspect of the present invention provides a method for diagnosing a motor stator winding fault, comprising: Collecting the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, performing spectrum analysis on the three-phase stator current and three-phase stator voltage to obtain voltage characteristic spectrum components and current characteristic spectrum components; Perform phase sequence analysis on the voltage characteristic spectrum components and current characteristic spectrum components to obtain positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The target asynchronous motor is in a normal state, and the negative sequence admittance is determined by the quantitative relationship between the negative sequence current and the negative sequence voltage; The target asynchronous motor is in a fault diagnosis state, and the positive and negative sequence transfer admittance is determined according to the quantitative relationship among the negative sequence admittance, positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The fault diagnosis result of the target asynchronous motor is determined according to the positive and negative sequence transfer admittance and the safe area, wherein the safe area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

[0007] According to the motor stator winding fault diagnosis method, the phase sequence analysis of the voltage characteristic spectrum component and the current characteristic spectrum component is performed to obtain the positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage, including: The calculation formulas for the positive sequence current and the negative sequence current are:

[0008] in, 、 、 is the current characteristic spectrum component of the three-phase stator current, , 、 and Indicates the positive sequence current, negative sequence current and zero sequence current of the target asynchronous motor in a normal state; The calculation formulas for the positive sequence voltage and the negative sequence voltage are:

[0009] in, 、 、 is the voltage characteristic spectrum component of the three-phase stator voltage, 、 and Indicates the positive-sequence voltage, negative-sequence voltage, and zero-sequence voltage of the target asynchronous motor in a normal state, wherein the normal state indicates that the target asynchronous motor is in system debugging or the motor is running healthily.

[0010] According to the motor stator winding fault diagnosis method, wherein the target asynchronous motor is in a normal state, the negative sequence admittance is determined by the quantitative relationship between the negative sequence current and the negative sequence voltage, including: Negative sequence admittance The calculation formula is:

[0011] in, represents the negative sequence current, Indicates negative sequence voltage; Also, when the target asynchronous motor leaves the factory or is first commissioned, the negative sequence admittance Perform tuning, the target asynchronous motor is in fault diagnosis state, and maintains negative sequence admittance Constant; or obtain the load and environment of the target asynchronous motor when it is running. If the change degree of the load and environment is greater than the preset change value, the negative sequence admittance is adjusted. Re-adjust; or obtain the running time of the target asynchronous motor. When the running time is greater than the preset time, the negative sequence admittance Recalibrate.

[0012] According to the motor stator winding fault diagnosis method, the method further includes: Get the nameplate data of the target asynchronous motor and perform negative sequence admittance according to the nameplate data The formula for tuning or retuning is:

[0013]

[0014] in is the negative sequence impedance, It is an imaginary unit. The nameplate data includes the stator resistance. , leakage reactance , rotor resistance , leakage reactance , excitation reactance and excitation resistance .

[0015] According to the motor stator winding fault diagnosis method, the method further includes: The negative sequence admittance is calculated using the average value method or the least square method. Perform tuning; The average value method includes collecting sample data within a preset period and calculating the negative sequence admittance of each sample data. , the average value of all the data is taken as the negative sequence admittance The calculation formula of the average value method is:

[0016] in, is the sampling data sequence identifier, is the number of sample data, and For the k Negative sequence voltage and negative sequence current in the group sample data, is the setting value of negative sequence admittance, is the average value of negative sequence admittance; The least square method includes collecting sample data within a preset period, and calculating the negative sequence voltage and negative sequence current Negative sequence admittance is calculated by least square method The least squares method is calculated as follows:

[0017] in, and are the average negative sequence voltage and the average negative sequence current of the sample data.

[0018] According to the motor stator winding fault diagnosis method, wherein the target asynchronous motor is in a fault diagnosis state, the positive and negative sequence transfer admittance is determined based on the quantitative relationship among the negative sequence admittance, the positive sequence current, the negative sequence current, the positive sequence voltage, and the negative sequence voltage, including: Positive and negative sequence transfer admittance The calculation formula is:

[0019] Among them, the positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage of the target asynchronous motor in the fault diagnosis state are 、 、 and , is the negative sequence admittance; And, calculate the positive and negative sequence transfer admittance using the average method or least squares method ; The average value method includes collecting sample data within a preset period and calculating the positive and negative sequence admittance of each sample data. , the average value of all sample data is taken as the positive and negative sequence admittance The calculation formula of the average value method is:

[0020] in, is the sampling data sequence identifier, is the number of sample data, 、 and are the positive sequence voltage, negative sequence voltage and positive sequence current in the kth group of sample data in the fault diagnosis state, is the setting value of positive and negative sequence admittance, is the average value of positive and negative sequence admittance; The least square method includes collecting sample data within a preset period, and calculating the negative sequence voltage and negative sequence current Positive and negative sequence admittance The least squares method is calculated as follows:

[0021] in, and are the average negative sequence voltage and current values ​​of the sample data.

[0022] According to the motor stator winding fault diagnosis method, the fault diagnosis result of the target asynchronous motor is determined based on the positive and negative sequence transfer admittance and the safe area, including: Determine whether the positive and negative sequence transfer admittances are in the safe area; if so, the target asynchronous motor is in a healthy state; otherwise, the target asynchronous motor is in a fault state; The target asynchronous motor is in a fault state, and the fault type is determined according to the amplitude and phase coordinates of the positive and negative sequence admittances, and the fault diagnosis result is determined according to the fault type.

[0023] Another aspect of an embodiment of the present invention provides a motor stator winding fault diagnosis device, comprising: The first module is used to collect the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, perform spectrum analysis on the three-phase stator current and three-phase stator voltage, and obtain voltage characteristic spectrum components and current characteristic spectrum components; The second module is used to perform phase sequence analysis on the voltage characteristic spectrum components and the current characteristic spectrum components to obtain positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The third module is used to determine the negative sequence admittance by the quantitative relationship between the negative sequence current and the negative sequence voltage when the target asynchronous motor is in a normal state; The fourth module is used to determine the positive and negative sequence transfer admittance according to the quantitative relationship among the negative sequence admittance, the positive sequence current, the negative sequence current, the positive sequence voltage and the negative sequence voltage when the target asynchronous motor is in a fault diagnosis state; The fifth module is used to determine the fault diagnosis result of the target asynchronous motor based on the positive and negative sequence transfer admittance and the safety area, wherein the safety area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

[0024] Another aspect of an embodiment of the present invention provides an electronic device, including a processor and a memory; The memory is used to store programs; The processor executes the program to implement the method described above.

[0025] Embodiments of the present invention further disclose a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium and execute the computer instructions, causing the computer device to perform the method described above.

[0026] The beneficial effects of the present invention are as follows: it adopts a non-invasive design, and only needs to collect the voltage signal and current signal of the motor, and real-time monitoring does not affect the normal operation of the equipment; the diagnostic process only uses parameters such as voltage and current, and can directly reuse the existing electrical parameter ports, without the need to install vibration or temperature sensors, which greatly reduces the diagnostic cost; it can identify a variety of fault types, and through the dual diagnosis of characteristic impedance amplitude and phase, it can identify various faults such as turn-to-turn short circuit, phase-to-phase insulation abnormality, parallel branch open circuit, high-resistance connection, etc.; the use of dynamic parameter estimation and anti-interference algorithm can eliminate the influence of nameplate parameter error and motor operating point change on the results, improve the adaptability of the model to voltage unstable working conditions, and the results are robust; the calculation is simple, the setting time is short, and long-term continuous online monitoring can be carried out. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1 Schematic diagram of a motor stator winding fault diagnosis system according to an embodiment of the present invention.

[0028] Figure 2 Schematic diagram of a data analysis module according to an embodiment of the present invention.

[0029] Figure 3 It is a flow chart of a motor stator winding fault diagnosis method according to an embodiment of the present invention.

[0030] Figure 4 It is a flow chart of a motor stator winding fault diagnosis method based on motor nameplate data according to an embodiment of the present invention.

[0031] Figure 5 It is a flow chart of a method for diagnosing motor stator winding faults by introducing voltage disturbance according to an embodiment of the present invention.

[0032] Figure 6 The present invention is a flowchart of a method for diagnosing motor stator winding faults by adjusting negative sequence admittance and positive and negative sequence admittance according to an embodiment of the present invention.

[0033] Figure 7 3 is a fault characteristic amplitude-phase distribution diagram of an embodiment of the present invention.

[0034] Figure 84 is a relationship diagram of the diagnostic coefficient, nameplate parameters and motor operating point according to an embodiment of the present invention.

[0035] Figure 9 3 is a distribution regularity diagram of the fault characteristics before and after the fault of the inter-turn short circuit embodiment of the present invention.

[0036] Figure 10 3 is a diagram showing the distribution of fault characteristics before and after a parallel branch open circuit fault according to an embodiment of the present invention.

[0037] Figure 11 Schematic diagram of a motor stator winding fault diagnosis device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. In the subsequent description, suffixes such as "module," "component," or "unit" used to represent elements are used solely to facilitate the description of the present invention and have no specific meaning in themselves. Therefore, "module," "component," or "unit" may be used interchangeably. "First," "second," and the like are used solely to distinguish technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. In this subsequent description, the consecutive numbering of method steps is for ease of review and understanding. In conjunction with the overall technical solution of the present invention and the logical relationship between the various steps, adjusting the order of implementation of the steps does not affect the technical effects achieved by the technical solution of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and should not be construed as limiting the present invention.

[0039] like Figure 1 and Figure 2 As shown, Figure 1 Schematic diagram of a motor stator winding fault diagnosis system, which includes a stator winding 100 of an asynchronous motor and a data analysis module 200; Figure 2is a schematic diagram of the data analysis module 200, which mainly collects current data and voltage data from the stator winding 100 through a detection coil group, performs spectrum analysis on the collected current data and voltage data, obtains corresponding component data (i.e., characteristic spectrum components), and then performs phase sequence analysis to obtain positive-sequence current, negative-sequence current, positive-sequence voltage, and negative-sequence voltage; when the target asynchronous motor is in a normal state (i.e., stable and healthy operation), the negative-sequence admittance is determined by the quantitative relationship between the negative-sequence current and the negative-sequence voltage; then, when the target asynchronous motor is in a fault diagnosis state, the positive- and negative-sequence transfer admittance is determined based on the quantitative relationship between the negative-sequence admittance, positive-sequence current, negative-sequence current, positive-sequence voltage, and negative-sequence voltage; and the fault diagnosis result of the target asynchronous motor is determined based on the positive- and negative-sequence transfer admittance and the safe area.

[0040] refer to Figure 3 、 4 , 5, and 6 are flow charts of the motor stator winding fault diagnosis method, where Figure 4 、 5 , The data acquisition module in 6 can refer to Figure 2 The data acquisition module shown.

[0041] for Figure 3 , which includes but is not limited to steps S100 to S500: S100 , collecting three-phase stator current and three-phase stator voltage of a target asynchronous motor in a normal state, performing spectrum analysis on the three-phase stator current and three-phase stator voltage, and obtaining voltage characteristic spectrum components and current characteristic spectrum components.

[0042] In some embodiments, during system debugging or motor health operation, the three-phase stator current of the asynchronous motor to be tested is collected. 、 、 , and extract the specific frequency component 、 、 , collect three-phase stator voltage 、 、 , and extract the component of a specific frequency (this frequency is called the characteristic frequency) 、 、 .

[0043] In some embodiments, healthy operation of the motor means that the motor is in rated operating conditions and a stable working environment.

[0044] S200 , performing phase sequence analysis on the voltage characteristic spectrum components and the current characteristic spectrum components to obtain positive sequence current, negative sequence current, positive sequence voltage, and negative sequence voltage.

[0045] In some embodiments, the positive sequence current and the negative sequence current are calculated as follows:

[0046] in, 、 、 is the current characteristic spectrum component of the three-phase stator current, , and Indicates the positive sequence current and negative sequence current of the target asynchronous motor in normal state; The calculation formulas for positive sequence voltage and negative sequence voltage are:

[0047] in, 、 、 is the voltage characteristic spectrum component of the three-phase stator voltage, and Indicates the positive-sequence voltage and negative-sequence voltage of the target asynchronous motor in a normal state, wherein the normal state indicates that the target asynchronous motor is in system debugging or the motor is running healthily.

[0048] Similarly, when the target asynchronous motor is in the fault diagnosis state, the three-phase stator current of the asynchronous motor to be detected is collected. 、 、 And the three-phase stator voltage 、 、 ; and perform spectrum analysis to obtain the component whose frequency is the characteristic frequency 、 、 and 、 、 ;right 、 、 Perform phase sequence analysis to calculate the three-phase stator positive sequence current , negative sequence current ;right 、 、 Perform phase sequence analysis to calculate the three-phase stator positive sequence voltage , negative sequence voltage The calculation method is the same as that when the target asynchronous motor is in a normal state, so it will not be described in detail.

[0049] S300: The target asynchronous motor is in a normal state, and the negative-sequence admittance is determined based on the quantitative relationship between the negative-sequence current and the negative-sequence voltage.

[0050] In some embodiments, the target asynchronous motor is in a normal state, and the negative sequence admittance The calculation formula is:

[0051] in, represents the negative sequence current, Indicates negative sequence voltage.

[0052] It should be noted that the process before and during the calculation of the negative-sequence admittance is acquisition and analysis, and the process after and during the calculation of the positive and negative-sequence admittance is a fault diagnosis process.

[0053] In some embodiments, the negative sequence admittance The calculation, tuning and retuning are as follows: (1) When the target asynchronous motor leaves the factory or is first debugged, the negative sequence admittance Perform tuning, the target asynchronous motor is in fault diagnosis state, and maintains negative sequence admittance It is understandable that when the target asynchronous motor is determined to have no fault, the repeated fault diagnosis only performs the processing after the negative-sequence admittance is obtained, and there is no need to collect the three-phase stator current and the three-phase stator voltage and calculate the negative-sequence admittance.

[0054] (2) Obtain the load and environment of the target asynchronous motor when it is running. If the change of the load and environment is greater than the preset change value, the negative sequence admittance is adjusted. Re-tuning is done, i.e. dynamically adjusting the motor during operation. Y nn , after the load condition or working environment of the motor changes to a certain extent, the negative sequence admittance Re-adjustment is performed. For example, after the system determines that no fault has occurred, when the load condition and working environment of the motor do not change much, only the fault diagnosis process is executed; when the load condition or working environment of the motor changes greatly, data collection, analysis and fault diagnosis processes need to be executed.

[0055] The changes in load conditions and (working) environment are determined based on preset change values. For example, the preset value for the load condition is 0.5-0.9. When the load rate exceeds 0.9, it is considered that the load change is large. For example, the preset value for the ambient temperature of the motor is 40-85°. When it exceeds 85°, it is considered that the load change is large.

[0056] (3) Obtain the running time of the target asynchronous motor. When the running time is greater than the preset time, the negative sequence admittance Recalibrate.

[0057] In some embodiments, the motor is tuned in real time during operation. Y nn, by setting a fixed time interval Δ T , when the accumulated system running time reaches Δ T After that, the negative sequence admittance Re-adjust and restart the interval time calculation. During fault diagnosis, after the system determines that no fault has occurred, when the accumulated running time of the motor does not reach Δ T When the running time of the motor reaches Δ T After that, the diagnosis including data collection, analysis and fault diagnosis process needs to be repeated, and the interval time is restarted.

[0058] In some embodiments, as Figure 4 As shown, it calculates the negative sequence admittance through the motor nameplate parameters , used to replace the acquisition and analysis steps During the tuning process, the circuit parameters of the motor are obtained according to the motor nameplate parameters or factory test parameters, where is the negative sequence impedance, It is an imaginary unit. The nameplate data includes the stator resistance. , leakage reactance , rotor resistance , leakage reactance , excitation reactance and excitation resistance Negative sequence admittance The calculation formula is:

[0059]

[0060] In some embodiments, the method further includes using the average value method or the least square method to calculate the negative sequence admittance. Perform adjustment.

[0061] like Figure 5 As shown, this implementation Figure 4 Based on the embodiment shown, the positive and negative sequence transfer admittance matrices are The setting calculation introduces the disturbance of grid voltage, in which the data analysis module is shown in Figure 2 In this embodiment, the fault diagnosis steps are repeated several times to measure the fault characteristics of the motor to be detected. The distribution pattern of the motor fault characteristics under healthy conditions The comparison results of the distribution regularity diagram are used as the basis for judgment. The specific operation steps are: (1) During system debugging or when the motor is in healthy working condition, several groups of signal data are collected. Each group of signals includes the motor stator voltage 、 、 and stator current 、 、 The negative sequence voltage component in each group of signals is obtained through spectrum analysis and phase sequence decomposition. and negative sequence current component ; (2) According to the negative sequence voltage in the multiple sets of signals collected and negative sequence current , calculate the negative sequence admittance by linear regression method ,Right now:

[0062] in and It is the average value of the negative sequence voltage component and the negative sequence current component in all sample data.

[0063] (3) Collect the three-phase stator current of the asynchronous motor to be tested 、 、 And the three-phase stator voltage 、 、 , and extract the positive and negative sequence current and voltage components of specific frequencies 、 、 、 ; (4) According to the positive and negative sequence current and voltage in the multiple sets of signals collected 、 、 、 and negative sequence admittance The quantitative relationship between them is used to calculate the positive and negative sequence transfer admittances respectively. ,Right now:

[0064] Take the positive and negative sequence transfer admittance As a fault characteristic, when When the value of is within the safe area, it is determined that no fault has occurred and the system repeats the above fault diagnosis process; when it is outside the safe area, it is determined that the motor has failed and the system The fault type is judged based on the amplitude and phase of the fault.

[0065] The average value method includes collecting sample data within a preset period and calculating the negative sequence admittance of each sample data. , the average value of all the data is taken as the negative sequence admittance The calculation formula of the average value method is:

[0066] in, is the sampling data sequence identifier, is the number of sample data, indicating and For the k Negative sequence voltage and negative sequence current in the group sample data, is the setting value of negative sequence admittance, The negative sequence admittance is the average value. Specifically, during the early debugging of the motor, it is considered that the motor is in a healthy state and the negative sequence voltage at the motor port is collected. and negative sequence current , according to the negative sequence current and voltage and Quantitative relationship, calculate the negative sequence admittance of the asynchronous motor .

[0067] The least square method includes collecting sample data within a preset period and calculating the negative sequence voltage. and negative sequence current Negative sequence admittance is calculated by least square method The least squares method is calculated as follows:

[0068] in, and is the average value of negative sequence voltage and negative sequence current in all sample data. Specifically, Y nn During the setting process, a number of voltage and current signal samples are collected in units of electrical cycles, and the negative sequence voltage and negative sequence current are extracted and the negative sequence admittance is calculated. Y nn , using each sample Y nn The average value of Y nn The setting value of .

[0069] S400: The target asynchronous motor is in a fault diagnosis state, and the positive-sequence transfer admittance is determined according to the quantitative relationship among the negative-sequence admittance, the positive-sequence current, the negative-sequence current, the positive-sequence voltage, and the negative-sequence voltage.

[0070] In some embodiments, the positive and negative sequence transfer admittance The calculation formula is:

[0071] Among them, the positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage of the target asynchronous motor in the fault diagnosis state are 、 、 、 ,and is the negative sequence admittance; In some embodiments, the positive and negative sequence transfer admittances are calculated using the average method or the least squares method. ; The average value method includes collecting sample data within a preset period and calculating the positive and negative sequence admittance of each sample data. , the average value of all sample data is taken as the positive and negative sequence admittance The calculation formula of the average value method is:

[0072] in, is the sampling data sequence identifier, is the number of sample data, 、 and are the positive sequence voltage, negative sequence voltage and positive sequence current in the kth group of sample data in the fault diagnosis state, is the setting value of positive and negative sequence admittance, is the average value of the positive and negative sequence admittance. Specifically, Y np In the measurement and calculation process, a number of voltage and current signal samples are collected in units of electrical cycles to calculate the positive and negative sequence transfer admittances respectively. Y np , using each sample Y np The average value of Y np estimated value of; The least square method involves collecting sample data within a preset period and calculating the negative sequence voltage. and negative sequence current The positive and negative sequence admittances are calculated by the least squares method. The least squares method is calculated as follows:

[0073] in, and is the average value of negative sequence voltage and negative sequence current of all sample data in the fault diagnosis state. Specifically, Y np In the measurement and calculation process, a number of voltage and current signal samples are collected in units of electrical cycles, and the positive and negative sequence transfer admittances are calculated using the least squares method and its derivative mathematical methods. In some embodiments, during the operation of the motor, Y nn andY np Perform setting calculations.

[0074] Figure 6 The embodiment shown also Y nn and Y np The setting calculation is performed by using the least square method to calculate the negative sequence admittance , positive and negative sequence transfer admittance Perform setting calculations, the calculation method is:

[0075] in: ,

[0076] N is the total amount of data collected during the measurement period.

[0077] The above embodiments are all Perform setting calculations and then use the measured data to Perform calculations. Figure 4 As shown, in this embodiment, and The setting calculations are performed simultaneously.

[0078] (1) Collect three-phase stator current 、 、 And the three-phase stator voltage 、 、 , and extract the positive and negative sequence current and voltage components of specific frequencies 、 、 、 ; (2) Repeat the acquisition and analysis steps several times, and use the least squares method to simultaneously calculate the negative sequence admittance based on the multiple sets of voltage and current data collected. , positive and negative sequence transfer admittance Perform the setting calculation:

[0079] in, , ,in N 2 is the total amount of data collected during the measurement period, 、 、 、 are the i-th time (1≤ i ≤N 2) Measured positive-sequence voltage, negative-sequence voltage, positive-sequence current, and negative-sequence current. is the voltage matrix The transpose of is a matrix The inverse matrix of .

[0080] Transfer admittance in positive and negative sequence As the fault characteristic, that is, according to the calculated The amplitude of is used to determine whether the asynchronous motor has a fault. When the value of is within the safe area, it is determined that no fault has occurred and the system repeats the above fault diagnosis process; when it is outside the safe area, it is determined that the motor has failed and the system The fault type is judged based on the amplitude and phase of the fault.

[0081] S500 , determining a fault diagnosis result of the target asynchronous motor according to the positive and negative sequence transfer admittance and the safety region, wherein the safety region is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

[0082] In some embodiments, it is determined whether the positive and negative sequence transfer admittances are in a safe area. If so, the target asynchronous motor is in a healthy state; otherwise, the target asynchronous motor is in a fault state. When the target asynchronous motor is in a fault state, the fault type is determined based on the amplitude and phase coordinates of the positive and negative sequence admittances, and the fault diagnosis result is determined based on the fault type.

[0083] In some embodiments, Figure 7 The fault characteristic amplitude phase distribution diagram of this embodiment is shown in FIG. 1 . When the calculated positive and negative sequence transfer admittance is If it falls within the safe area (i.e. area 1), it is determined that the motor has not failed. If it falls outside the safe area, the motor is judged to be faulty and The amplitude and phase coordinates are used to determine the fault type. Figure 7 Regions 2, 3, 4, and 5 correspond to parallel branch open circuit faults, phase-to-phase insulation abnormality faults, turn-to-turn short circuit faults, and high-resistance connection faults, respectively. lie in Figure 7 If the motor is in an area other than the above areas 1 to 5, it is determined that other abnormal faults have occurred in the motor.

[0084] In this embodiment, the value of Ω1 corresponding to the no-fault condition is The values ​​of Ω2 to Ω5 corresponding to the parallel branch open circuit fault, phase-to-phase insulation abnormality fault, turn-to-turn short circuit fault, and high-resistance connection fault are:

[0085]

[0086]

[0087]

[0088] This embodiment uses dynamic parameter estimation to eliminate the impact of nameplate parameter errors and changes in the motor operating point on the results, making it more adaptable to changes in the motor's operating state than the fixed parameter method. It actively introduces grid voltage disturbances to simulate actual grid fluctuation scenarios, improving the model's adaptability to voltage instability conditions. By repeating several measurements, a fault feature distribution pattern diagram is generated and the overlapping area is compared with the healthy state distribution (threshold determination) to avoid single sampling errors, circumvent random noise interference, and enhance the robustness of the results.

[0089] Figure 8 The diagram below shows the relationship between the diagnostic coefficient, nameplate parameters and the motor operating point. and It is related to the actual operating state of the motor. Directly setting the parameters using the nameplate will result in large errors. In addition, in actual operation, the operation of the motor will always be affected by the grid voltage disturbance. Ideally, the grid voltage disturbance will not affect the sensitivity of the impedance parameter to stator faults. However, in reality, the impedance parameter and There is an error in the setting of the impedance parameter, which will be amplified by the grid disturbance, thereby greatly reducing the sensitivity of the impedance parameter to stator faults. and The accuracy of the tuning algorithm is the key to reducing the impact of operating point changes and grid disturbances on fault characteristics. and Estimation is performed to reduce the impact of operating point changes and grid disturbances on fault characteristics.

[0090] Figure 9 The fault characteristics before and after the fault of an inter-turn short circuit embodiment The distribution pattern diagram. Its distribution clearly reflects the fault characteristics before and after the fault The change in impedance is demonstrated using the As the feasibility of the fault characteristics, Figure 10 The fault characteristics before and after the fault of a parallel branch open circuit fault embodiment The distribution law diagram shows that after the failure The amplitude of is significantly increased, which is significantly different from that before the fault, and the phase distribution is relatively concentrated. Under different fault conditions, There is a significant difference in the amplitude and phase distribution of . Therefore, the motor health status can be diagnosed based on the changes in the amplitude and phase of .

[0091] Figure 11 FIG. 1 is a diagram of a motor stator winding fault diagnosis and analysis device according to an embodiment of the present invention. The device includes a first module 1110 , a second module 1120 , a third module 1130 , a fourth module 1140 and a fifth module 1150 .

[0092] Among them, the first module is used to collect the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, perform spectrum analysis on the three-phase stator current and three-phase stator voltage, and obtain voltage characteristic spectrum components and current characteristic spectrum components; the second module is used to perform phase sequence analysis on the voltage characteristic spectrum components and the current characteristic spectrum components to obtain positive-sequence current, negative-sequence current, positive-sequence voltage and negative-sequence voltage; the third module is used to determine the negative-sequence admittance by the quantitative relationship between the negative-sequence current and the negative-sequence voltage when the target asynchronous motor is in a normal state; the fourth module is used to determine the positive and negative sequence transfer admittance according to the quantitative relationship between the negative-sequence admittance, positive-sequence current, negative-sequence current, positive-sequence voltage and negative-sequence voltage when the target asynchronous motor is in a fault diagnosis state; the fifth module is used to determine the fault diagnosis result of the target asynchronous motor based on the positive and negative sequence transfer admittance and the safe area, wherein the safe area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

[0093] Exemplarily, with the cooperation of the first to fifth modules in the device, the embodiment device can implement any of the aforementioned motor stator winding fault diagnosis methods, that is, collecting the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, performing spectral analysis on the three-phase stator current and the three-phase stator voltage to obtain voltage characteristic spectrum components and current characteristic spectrum components; performing phase sequence analysis on the voltage characteristic spectrum components and the current characteristic spectrum components to obtain positive-sequence current, negative-sequence current, positive-sequence voltage and negative-sequence voltage; the target asynchronous motor is in a normal state, and the negative-sequence admittance is determined by the quantitative relationship between the negative-sequence current and the negative-sequence voltage; the target asynchronous motor is in a fault diagnosis state, and the positive- and negative-sequence transfer admittance is determined according to the quantitative relationship between the negative-sequence admittance, positive-sequence current, negative-sequence current, positive-sequence voltage and negative-sequence voltage; the fault diagnosis result of the target asynchronous motor is determined based on the positive- and negative-sequence transfer admittance and the safe area, wherein the safe area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state. The beneficial effects of the present invention are as follows: it adopts a non-invasive design, and only needs to collect the voltage signal and current signal of the motor, and real-time monitoring does not affect the normal operation of the equipment; the diagnostic process only uses parameters such as voltage and current, and can directly reuse the existing electrical parameter ports, without the need to install vibration or temperature sensors, which greatly reduces the diagnostic cost; it can identify a variety of fault types, and through the dual diagnosis of characteristic impedance amplitude and phase, it can identify various faults such as turn-to-turn short circuit, phase-to-phase insulation abnormality, parallel branch open circuit, high-resistance connection, etc.; the use of dynamic parameter estimation and anti-interference algorithm can eliminate the influence of nameplate parameter error and motor operating point change on the results, improve the adaptability of the model to voltage unstable working conditions, and the results are robust; the calculation is simple, the setting time is short, and long-term continuous online monitoring can be carried out.

[0094] An embodiment of the present invention further provides an electronic device, the electronic device including a processor and a memory; The memory stores a program; The processor executes the program to perform the aforementioned motor stator winding fault diagnosis method; the electronic device has the function of carrying and running the motor stator winding fault diagnosis software system provided by the embodiment of the present invention, such as a personal computer, a minicomputer, a main frame, a workstation, a network or distributed computing environment, a separate or integrated computer platform, or communicates with a charged particle tool or other imaging device, etc.

[0095] An embodiment of the present invention further provides a computer-readable storage medium, wherein the storage medium stores a program, and the program is executed by a processor to implement the motor stator winding fault diagnosis method as described above.

[0096] In some optional embodiments, the function / operation mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the function / operation involved, the two boxes shown in succession can actually be executed substantially simultaneously or the boxes can sometimes be executed in reverse order. In addition, the embodiment presented and described in the flow chart of the present invention is provided in an exemplary manner for the purpose of providing a more comprehensive understanding of the technology. The disclosed method is not limited to the operation and logic flow presented herein. Optional embodiments are contemplated in which the order of the various operations is changed and the sub-operations described as a part of a larger operation are performed independently.

[0097] An embodiment of the present invention further discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium and execute the computer instructions, causing the computer device to perform the aforementioned motor stator winding fault diagnosis method.

[0098] Furthermore, although the present invention is described in the context of functional modules, it should be understood that, unless otherwise indicated, one or more of the functions and / or features described may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It will also be understood that a detailed discussion of the actual implementation of each module is not necessary for understanding the present invention. More specifically, given the properties, functions, and internal relationships of the various functional modules in the devices disclosed herein, the actual implementation of the module will be understood within the ordinary skill of an engineer. Therefore, a person skilled in the art using ordinary skill will be able to implement the present invention set forth in the claims without undue experimentation. It will also be understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0099] If the functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage media include various media capable of storing program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0100] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0101] More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic devices), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting, or processing it in another suitable manner as necessary, and then storing it in a computer memory.

[0102] It should be understood that various components of the present invention may be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods may be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof may be used: a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

[0103] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0104] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

[0105] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A motor stator winding fault diagnosis method, characterized in that: include: Collecting the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, performing spectrum analysis on the three-phase stator current and three-phase stator voltage to obtain voltage characteristic spectrum components and current characteristic spectrum components; Perform phase sequence analysis on the voltage characteristic spectrum components and current characteristic spectrum components to obtain positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The target asynchronous motor is in a normal state, and the negative sequence admittance is determined by the quantitative relationship between the negative sequence current and the negative sequence voltage; The target asynchronous motor is in a fault diagnosis state, and the positive and negative sequence transfer admittance is determined according to the quantitative relationship among the negative sequence admittance, positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The fault diagnosis result of the target asynchronous motor is determined according to the positive and negative sequence transfer admittance and the safe area, wherein the safe area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

2. The motor stator winding fault diagnosis method according to claim 1, characterized in that: The phase sequence analysis of the voltage characteristic spectrum component and the current characteristic spectrum component is performed to obtain the positive sequence current, the negative sequence current, the positive sequence voltage and the negative sequence voltage, including: The calculation formulas for the positive sequence current and the negative sequence current are: ； in, 、 、 is the current characteristic spectrum component of the three-phase stator current, , 、 and Indicates the positive sequence current, negative sequence current and zero sequence current of the target asynchronous motor in a normal state; The calculation formulas for the positive sequence voltage and the negative sequence voltage are: ； in, 、 、 is the voltage characteristic spectrum component of the three-phase stator voltage, 、 and Indicates the positive-sequence voltage, negative-sequence voltage, and zero-sequence voltage of the target asynchronous motor in a normal state, wherein the normal state indicates that the target asynchronous motor is in system debugging or the motor is running healthily.

3. The motor stator winding fault diagnosis method according to claim 1, characterized in that: The target asynchronous motor is in a normal state, and the negative sequence admittance is determined according to the quantitative relationship between the negative sequence current and the negative sequence voltage, including: Negative sequence admittance The calculation formula is: ； in, represents the negative sequence current, Indicates negative sequence voltage; Also, when the target asynchronous motor leaves the factory or is first commissioned, the negative sequence admittance Perform tuning, the target asynchronous motor is in fault diagnosis state, and maintains negative sequence admittance Constant; or obtain the load and environment of the target asynchronous motor when it is running. If the change degree of the load and environment is greater than the preset change value, the negative sequence admittance is adjusted. Re-adjust; or obtain the running time of the target asynchronous motor. When the running time is greater than the preset time, the negative sequence admittance Recalibrate.

4. The motor stator winding fault diagnosis method according to claim 3, characterized in that: The method further comprises: Get the nameplate data of the target asynchronous motor and perform negative sequence admittance according to the nameplate data The formula for tuning or retuning is: ； ； in is the negative sequence impedance, in imaginary units, and the nameplate data includes the stator resistance , leakage reactance , rotor resistance , leakage reactance , excitation reactance and excitation resistance .

5. The motor stator winding fault diagnosis method according to claim 3, characterized in that: The method further comprises: The negative sequence admittance is calculated using the average value method or the least square method. Perform tuning; The average value method includes collecting sample data within a preset period and calculating the negative sequence admittance of each sample data. , the average value of all the data is taken as the negative sequence admittance The calculation formula of the average value method is: ； in, is the sampling data sequence identifier, is the number of sample data, and For the k Negative sequence voltage and negative sequence current in the group sample data, is the setting value of negative sequence admittance, is the average value of negative sequence admittance; The least square method includes collecting sample data within a preset period, and calculating the negative sequence voltage and negative sequence current Negative sequence admittance is calculated by least square method The least squares method is calculated as follows: ； in, and are the average negative sequence voltage and the average negative sequence current of the sample data.

6. The motor stator winding fault diagnosis method according to claim 1, characterized in that: The target asynchronous motor is in a fault diagnosis state, and the positive and negative sequence transfer admittances are determined according to the quantitative relationship among the negative sequence admittance, the positive sequence current, the negative sequence current, the positive sequence voltage, and the negative sequence voltage, including: Positive and negative sequence transfer admittance The calculation formula is: ； Among them, the positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage of the target asynchronous motor in the fault diagnosis state are 、 、 and , is the negative sequence admittance; And, calculate the positive and negative sequence transfer admittance using the average method or least squares method ; The average value method includes collecting sample data within a preset period and calculating the positive and negative sequence admittance of each sample data. , the average value of all sample data is taken as the positive and negative sequence admittance The calculation formula of the average value method is: ； in, is the sampling data sequence identifier, is the number of sample data, 、 and are the positive sequence voltage, negative sequence voltage and positive sequence current in the kth group of sample data in the fault diagnosis state, is the setting value of positive and negative sequence admittance, is the average value of positive and negative sequence admittance; The least square method includes collecting sample data within a preset period, and calculating the negative sequence voltage and negative sequence current Positive and negative sequence admittance The least squares method is calculated as follows: ； in, and are the average negative sequence voltage and current values ​​of the sample data.

7. The motor stator winding fault diagnosis method according to claim 1, characterized in that: Determining the fault diagnosis result of the target asynchronous motor according to the positive and negative sequence transfer admittance and the safe area includes: Determine whether the positive and negative sequence transfer admittances are in the safe area; if so, the target asynchronous motor is in a healthy state; otherwise, the target asynchronous motor is in a fault state; The target asynchronous motor is in a fault state, and the fault type is determined according to the amplitude and phase coordinates of the positive and negative sequence admittances, and the fault diagnosis result is determined according to the fault type.

8. A motor stator winding fault diagnosis device, characterized in that: include: The first module is used to collect the three-phase stator current and three-phase stator voltage of the target asynchronous motor in a normal state, perform spectrum analysis on the three-phase stator current and three-phase stator voltage, and obtain voltage characteristic spectrum components and current characteristic spectrum components; The second module is used to perform phase sequence analysis on the voltage characteristic spectrum components and the current characteristic spectrum components to obtain positive sequence current, negative sequence current, positive sequence voltage and negative sequence voltage; The third module is used to determine the negative sequence admittance by the quantitative relationship between the negative sequence current and the negative sequence voltage when the target asynchronous motor is in a normal state; The fourth module is used to determine the positive and negative sequence transfer admittance according to the quantitative relationship among the negative sequence admittance, the positive sequence current, the negative sequence current, the positive sequence voltage and the negative sequence voltage when the target asynchronous motor is in a fault diagnosis state; The fifth module is used to determine the fault diagnosis result of the target asynchronous motor based on the positive and negative sequence transfer admittance and the safety area, wherein the safety area is used to determine whether the target asynchronous motor is in a normal state or a fault diagnosis state.

9. An electronic device, characterized in that: including a processor and a memory; The memory is used to store programs; The processor executes the program to implement the motor stator winding fault diagnosis method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The storage medium stores a program, and the program is executed by a processor to implement the motor stator winding fault diagnosis method according to any one of claims 1 to 7.

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