A method and system for diagnosing a turn-to-turn short circuit fault of a stator winding of a doubly-fed asynchronous motor

Abstract

The application relates to the technical field of power equipment fault diagnosis, and discloses a doubly-fed asynchronous motor stator winding inter-turn short-circuit fault diagnosis method and system. The method extracts a magnetic flux residual through a mathematical model of a doubly-fed asynchronous motor before and after a fault, realizes fault detection through comparison between the amplitude of the magnetic flux residual and an adaptive threshold value, further realizes fault phase positioning according to the phase of the magnetic flux residual, and compared with an existing model-based method, the method reduces the calculation workload, realizes accurate fault positioning and fault grade determination, and can realize online rapid fault diagnosis.

Description

Technical Field

[0001] This invention relates to the field of power equipment fault diagnosis technology, and in particular to a method and system for diagnosing inter-turn short-circuit faults in the stator winding of a doubly fed asynchronous motor. Background Technology

[0002] Doubly fed asynchronous motors have become key equipment in energy conversion and storage fields such as wind power generation and pumped storage due to their core advantages such as high operational reliability, excellent cost performance and outstanding mechanical efficiency. Their operational stability directly affects the safe and efficient operation of the entire energy system, and their application rate in the above fields is showing a continuous upward trend.

[0003] However, under long-term high load and complex operating conditions, the stator windings of doubly-fed asynchronous motors are prone to failure due to factors such as insulation aging, mechanical vibration, and electromagnetic stress. Among these, stator inter-turn short circuit faults are one of the most common types of faults. According to industry survey data, stator inter-turn short circuit faults account for as high as 37% of the various common faults in doubly-fed asynchronous motors. When this fault occurs, insulation failure occurs between some turns of the stator coil winding, forming a short circuit. A large instantaneous current is generated in the short circuit, leading to local overheating. At the same time, the overheating and abnormal electromagnetic effects will further spread to the adjacent normal windings, causing accelerated deterioration of the insulation performance of the normal windings. If accurate diagnosis and treatment are not achieved in the early stages of the fault, the fault will continue to expand, eventually causing irreversible structural damage to key components such as the motor stator core and windings, and even inducing more serious faults such as phase-to-phase short circuits and ground short circuits. This not only leads to motor shutdown for maintenance but may also trigger a chain reaction of faults in the entire energy system, causing huge economic losses and safety risks. Therefore, accurate diagnosis in the early stages of stator inter-turn short-circuit faults is a key prerequisite for ensuring the reliable operation of doubly-fed asynchronous motors and avoiding serious damage and unnecessary shutdowns. Currently, diagnostic techniques for stator inter-turn short-circuit faults in doubly-fed asynchronous motors have become a research hotspot in the industry. Various detection methods have been publicly reported in related fields, which can be categorized into three types based on their technical principles: signal-based diagnostic methods, model-based diagnostic methods, and artificial intelligence-based diagnostic methods. The technical characteristics and limitations of each method are as follows: For signal-based diagnostic methods, fault location can be achieved through mature signal processing techniques such as Fourier transform, wavelet transform, and Hilbert-Huang transform. However, these methods have significant limitations in practical engineering applications. On the one hand, the acquisition of some signals (such as axial leakage magnetic field signals) requires the addition of dedicated sensors to the motor, increasing equipment modification costs and installation complexity, thus reducing feasibility. On the other hand, these methods are not robust to operating condition disturbances (such as grid voltage fluctuations and load abrupt changes), easily leading to misdiagnosis or missed diagnosis, making it difficult to simultaneously achieve feasibility, simplicity, and robustness. For model-based diagnostic methods, existing model-based diagnostic methods also employ observer types such as adaptive observers and sliding mode observers. However, the design of such observers relies on complex nonlinear control theory, which not only makes model construction cumbersome but also requires the introduction of many adjustable parameters, increasing computational complexity and hindering online diagnostics on industrial controllers with limited computing power (such as PLCs and embedded controllers). Artificial intelligence-based diagnostic methods have several insurmountable drawbacks: First, model training relies on massive amounts of fault sample data, while acquiring stator turn-to-turn short-circuit fault samples of different fault phases and fault levels in industrial scenarios is extremely costly and has a long data acquisition cycle. Second, the inference process of deep learning and other models is computationally complex and has stringent requirements for hardware computing power, making it difficult to implement online diagnosis on real-time controllers in industrial settings. Furthermore, the model training process consumes a significant amount of time and computing resources, which is not conducive to engineering applications. It is evident that existing methods suffer from high computational complexity and incomplete diagnostic functionality. Summary of the Invention

[0004] This invention provides a method and system for diagnosing inter-turn short-circuit faults in the stator winding of a doubly fed asynchronous motor, in order to solve the problems of high computational complexity and incomplete diagnostic functions in the prior art.

[0005] In a first aspect, this application provides a method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, including: Construct a calculation model for the flux linkage of the first doubly-fed asynchronous motor; Construct a calculation model for the flux linkage of the second doubly-fed asynchronous motor; The flux linkage residual is determined based on the first doubly-fed asynchronous motor flux linkage calculation model and the second doubly-fed asynchronous motor flux linkage calculation model. Fault detection is performed based on the amplitude and threshold of the flux linkage residual; After a fault is detected, stator and rotor flux linkage residual vectors are constructed under different fault phase conditions in a three-phase coordinate system. The stator and rotor flux linkage residual vectors under different fault phase conditions in the three-phase coordinate system are transformed to... In the coordinate system, the faulty phase is located.

[0006] In a second aspect, this application provides a fault diagnosis system for inter-turn short circuits in the stator winding of a doubly fed asynchronous motor, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method described in the first aspect above.

[0007] The present invention has the following beneficial effects: The present application discloses a method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor. By extracting the flux linkage residual from the mathematical model of the doubly-fed asynchronous motor before and after the fault, the method achieves fault detection by comparing the amplitude of the flux linkage residual with an adaptive threshold. Furthermore, it locates the fault phase based on the phase of the flux linkage residual. Compared with existing model-based methods, this method reduces the computational workload, achieves accurate fault location and fault level determination, and enables rapid online fault diagnosis.

[0008] In a further technical solution, a short-circuit turns characteristic factor was designed to represent the degree of impact of inter-turn short-circuit faults on the motor, which can quickly determine the degree of impact of inter-turn short-circuit faults on the motor.

[0009] In addition to the objectives, features and advantages described above, the present invention has other objectives, features and advantages.

[0010] The present invention will now be described in further detail with reference to the figures. Attached Figure Description

[0011] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is one of the flowcharts of a preferred embodiment of the present invention for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor; Figure 2 This is the second flowchart of a preferred embodiment of the present invention for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor; Figure 3 is a schematic diagram of the fault diagnosis experiment results under the fault diagnosis result of inter-turn short circuit in the stator winding of phase A according to a preferred embodiment of the present invention. Detailed Implementation

[0012] The technical solution of the present invention will be clearly and completely described below. 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.

[0013] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms "an" or "a," and similar terms, do not indicate a quantity limitation, but rather indicate the presence of at least one.

[0014] It should be understood that although existing technologies have disclosed various methods for diagnosing stator inter-turn short-circuit faults in doubly-fed asynchronous motors based on residual information, two core technical problems still urgently need to be solved in practical engineering applications: First, high computational complexity: Existing methods require the design of complex observers, such as adaptive observers and sliding mode observers, or cumbersome signal decomposition, such as wavelet transform and Hilbert-Huang transform, or reliance on high-computing-power artificial intelligence models, resulting in a large computational workload and making it difficult to achieve rapid online diagnosis on low-cost hardware platforms; how to construct residual-based fault detection indicators with low computational cost, while avoiding complex observer design, signal decomposition, or additional sensor measurements, has become a key research hotspot in the industry. Second, incomplete diagnostic functions: Some existing methods can only achieve fault detection (determining whether a fault has occurred), but cannot further determine the fault phase (i.e., fault phase location) and fault severity (i.e., fault level determination), which requires a comprehensive inspection of the motor stator windings during subsequent maintenance, increasing maintenance workload and downtime, and hindering the rapid restoration of motor operation. Based on this, this application provides a stator turn-to-turn short-circuit fault diagnosis technology for doubly-fed asynchronous motors that can simultaneously solve the above two problems. While reducing computational complexity and meeting the requirements of online diagnosis, it realizes the integrated functions of fault detection, fault phase location and fault level determination, providing technical support for efficient maintenance and reliable operation of motors.

[0015] Please see Figure 1 This application provides a method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, comprising: Construct a calculation model for the flux linkage of the first doubly-fed asynchronous motor; Construct a calculation model for the flux linkage of the second doubly-fed asynchronous motor; The flux linkage residual is determined based on the first doubly-fed asynchronous motor flux linkage calculation model and the second doubly-fed asynchronous motor flux linkage calculation model. Fault detection is performed based on the amplitude and threshold of the flux linkage residual; After a fault is detected, stator and rotor flux linkage residual vectors are constructed under different fault phase conditions in a three-phase coordinate system. The stator and rotor flux linkage residual vectors under different fault phase conditions in the three-phase coordinate system are transformed to... In the coordinate system, the faulty phase is located.

[0016] The above-mentioned method for diagnosing inter-turn short circuit faults in the stator winding of a doubly-fed asynchronous motor extracts flux linkage residuals from the mathematical model of the doubly-fed asynchronous motor before and after the fault. Fault detection is achieved by comparing the amplitude of the flux linkage residuals with an adaptive threshold. Furthermore, the fault phase is located based on the phase of the flux linkage residuals. Compared with existing model-based methods, this method reduces the computational workload, achieves accurate fault location and fault level determination, and enables rapid online fault diagnosis.

[0017] Optionally, constructing the flux linkage calculation model for the first doubly-fed asynchronous motor includes: The flux linkage of the doubly-fed asynchronous motor is calculated using the voltage equation. Magnetic Link The definition is as follows: ; In the formula, The stator flux linkage of phase A is obtained through the voltage equation. The B-phase stator flux linkage is obtained through the voltage equation. The C-phase stator flux linkage is obtained through the voltage equation. The rotor flux linkage of phase A is obtained through the voltage equation. The B-phase rotor flux linkage is obtained through the voltage equation. The rotor flux linkage of phase A is obtained through the voltage equation. For the flux linkage of the short-circuited winding; The calculation satisfies the following relationship: ; In the formula, For voltage matrix, For the current matrix, This is the resistance matrix under inter-turn short-circuit fault conditions. , , These are the A-phase voltage, B-phase voltage, and C-phase voltage of the stator of the doubly-fed asynchronous motor. , , These are the A-phase current, B-phase current, and C-phase current of the stator of the doubly-fed asynchronous motor. , , These are the A-phase voltage, B-phase voltage, and C-phase voltage of the rotor of the doubly-fed asynchronous motor. , , These are the A-phase current, B-phase current, and C-phase current of the rotor of the doubly-fed asynchronous motor. This refers to the short-circuit current in the inter-turn short-circuit loop.

[0018] Specifically: ; For stator winding resistance, For rotor winding resistance, The resistance in the inter-turn short-circuit loop. The short-circuit ratio specifies the ratio of the number of short-circuited turns in the sub-faulted phase to the total number of turns.

[0019] Optionally, the construction of the second doubly-fed asynchronous motor flux linkage calculation model includes: The flux linkage of the doubly-fed asynchronous motor is calculated using the flux linkage equation. Magnetic Link The definition is as follows: , The calculation satisfies the following relationship: ; In the formula, The inductance matrix of the doubly-fed asynchronous motor satisfies the following relationship: ; In the formula, For the inductor submatrix, and Let be the self-inductance matrix. and For mutual inductance matrix, The mutual inductance coefficient between the normal portion of the stator X-phase winding and the short-circuit circuit after the fault is given by, where, , This is the self-inductance of the short-circuit loop.

[0020] Specifically, the formulas for calculating the variables in the inductance matrix are as follows: .

[0021] In the formula, For the mutual inductance between the stator winding and the rotor winding, and The leakage inductance of the stator and rotor windings are respectively. It is the angle between the axis of the rotor phase a winding and the axis of the stator phase A winding.

[0022] Optionally, determining the flux linkage residual includes: The flux linkage residual is defined as follows: ; It is worth noting that, Specifically, it refers to any one of the elements within the parentheses, and each element is calculated as follows: in, The calculation formula is as follows: ; In the formula, For the first doubly-fed asynchronous motor flux linkage, For the second doubly-fed asynchronous motor flux linkage, The resistance matrix is ​​obtained by subtracting the voltage equations under normal and fault conditions. The current matrix is ​​obtained by subtracting the current under normal and fault conditions. This is the inductance matrix.

[0023] Specifically, The expression is: ; The expression is: ; The expression is: .

[0024] Furthermore, in this application, fault diagnosis variables are used. Fault detection is achieved by comparing with the diagnostic threshold T.

[0025] Optionally, the fault detection based on the amplitude and threshold of the flux linkage residual includes: Set an adaptive threshold T for fault diagnosis that satisfies the following relationship: ; Define fault diagnosis variables It satisfies the following relationship: ; In the formula, The flux linkage residual vector is... The sliding average value is represented by a sliding window time of one phase current cycle. Based on fault diagnosis variables and adaptive fault diagnosis thresholds, the determination of whether a fault has occurred satisfies the following relationship: ; In the formula, This is the result of fault diagnosis.

[0026] The construction of stator and rotor flux linkage residual vectors under different fault phase conditions in a three-phase coordinate system includes: The stator flux residues under different fault phase conditions are set as follows: ; The rotor flux residues under different fault phase conditions are as follows: ; Therefore, the stator flux residue is calculated as follows when phase A fails: ; In the formula, For short-circuit ratio, For stator winding resistance, This is the short-circuit current. For magnetizing inductance, This refers to the mutual inductance between the stator winding and the rotor winding.

[0027] The rotor flux linkage residual is calculated as follows: ; In the formula, The angle between the axis of rotor phase a winding and the axis of stator phase A winding; When phase B fails, the stator flux residue is calculated as follows: ; The rotor flux linkage residual is calculated as follows: ; When a C-phase fault occurs, the stator flux residue is calculated as follows: ; The rotor flux linkage residual is calculated as follows: ; The short-circuit loop flux residual is set to be under different fault phase conditions. ; When phase A is faulted, the short-circuit loop flux residue is as follows: ; When a phase B fault is assumed, the short-circuit loop flux residual is as follows: ; When a phase C fault is assumed, the short-circuit loop flux residue is as follows: .

[0028] In other words, the flux linkage residuals when inter-turn short circuits occur in different phases are shown in Tables 1 and 2.

[0029] Table 1. Stator and rotor flux linkage residuals under different fault phase conditions

[0030] Table 2. Short-circuit loop flux residues under different fault phase conditions

[0031] Furthermore, fault phase location is achieved through the phase K of the flux linkage residual, and the short-circuit turn number characteristic factor is used. / T is used to indicate the degree of impact of inter-turn short-circuit faults on the motor.

[0032] Optionally, the stator and rotor flux linkage residual vectors under different fault phase conditions in the three-phase coordinate system are transformed to... In a coordinate system, including: set up When phase A is faulted in the coordinate system, the residual vector is as follows: ; When phase B fails, the residual vector is as follows: ; During a C-phase fault, the residual vector is as follows: .

[0033] In other words, the stator flux linkage residual vector under different fault phase conditions in the αβ coordinate system is defined, as shown in Table 3.

[0034] Table 3 Ideal stator flux linkage residual vector under different fault phase conditions in coordinate system

[0035] Optionally, the fault location phase includes: Sure The vector angle K of the flux linkage residual in the coordinate system is as follows: ; In the formula, and For the stator flux linkage residual vector in Components in the coordinate system; according to The vector angle K of the flux linkage residual in the coordinate system locates the fault phase, as follows: When K = 0, it indicates a phase A fault; when K = -π / 3, it indicates a phase B fault; and when K = π / 3, it indicates a phase C fault.

[0036] In other words, the flux linkage residual vector angles under different inter-turn short-circuit faults are summarized in Table 4.

[0037] Table 4. Flux Residual Vector Angle under Different Inter-Turn Short Circuit Faults

[0038] The following example illustrates the effectiveness of the aforementioned method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, using experimental results. Figure 2The experimental results for this embodiment are presented, and the main parameters used in the experimental results are shown in Table 5.

[0039] Table 5 Main parameters of doubly-fed asynchronous motor

[0040] To verify the effectiveness of the proposed method, a C-phase inter-turn short-circuit fault (μ = 0.4) was added to the established doubly-fed asynchronous motor model at time 2s. The simulation results are shown in Figures 3(a)-3(e). Figure 3(a) shows the stator current. The waveform; Figure 3(b) shows the flux linkage residual. The waveform; Figure 3(c) shows the variable. and The waveform of variable K is shown in Figure 3(d); the waveform of variable P is shown in Figure 3(e).

[0041] As shown in Figure 3(c), the stator fault current waveform indicates that the inter-turn fault in phase C causes an imbalance in the three-phase current, with the phase C current exhibiting the largest amplitude. The flux linkage residual in Figure 3(c) is essentially zero before the fault; however, after the fault occurs... The relationship in the coordinate system satisfies the flux linkage residual relationship for phase C fault in Table 3.

[0042] An inter-turn short-circuit fault causes the flux linkage residual to be non-zero; once... If the value is greater than the threshold T, then F is set to 1, and the fault diagnosis method begins calculating the vector angle of the flux linkage residual. Based on: ; The value of K is π / 3, therefore the fault can be determined to occur in phase C. The time from fault occurrence to accurate fault location is 4.3 ms. It is worth noting that, due to / T = 54 ( = 92.4, T = 1.7), indicating that the fault is quite serious at this point.

[0043] This application also provides a system for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the above-described method. This system for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor can implement various embodiments of the above-described method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, and achieves the same beneficial effects; further details are omitted here.

[0044] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, characterized in that, include: Construct a calculation model for the flux linkage of the first doubly-fed asynchronous motor; Construct a calculation model for the flux linkage of the second doubly-fed asynchronous motor; The flux linkage residual is determined based on the first doubly-fed asynchronous motor flux linkage calculation model and the second doubly-fed asynchronous motor flux linkage calculation model. Fault detection is performed based on the amplitude and threshold of the flux linkage residual; After a fault is detected, stator and rotor flux linkage residual vectors are constructed under different fault phase conditions in a three-phase coordinate system. The stator and rotor flux linkage residual vectors under different fault phase conditions in the three-phase coordinate system are transformed to... In the coordinate system, locate the faulty phase; The construction of the first doubly-fed asynchronous motor flux linkage calculation model includes: The flux linkage of the doubly-fed asynchronous motor is calculated using the voltage equation. Magnetic Link The definition is as follows: ； In the formula, The stator flux linkage of phase A is obtained through the voltage equation. The B-phase stator flux linkage is obtained through the voltage equation. The C-phase stator flux linkage is obtained through the voltage equation. The rotor flux linkage of phase A is obtained through the voltage equation. The B-phase rotor flux linkage is obtained through the voltage equation. The rotor flux linkage of phase A is obtained through the voltage equation. For the flux linkage of the short-circuited winding; The calculation satisfies the following relationship: ； In the formula, For voltage matrix, For the current matrix, This is the resistance matrix under inter-turn short-circuit fault conditions. , , These are the A-phase voltage, B-phase voltage, and C-phase voltage of the stator of the doubly-fed asynchronous motor. , , These are the A-phase current, B-phase current, and C-phase current of the stator of the doubly-fed asynchronous motor. , , These are the A-phase voltage, B-phase voltage, and C-phase voltage of the rotor of the doubly-fed asynchronous motor. , , These are the A-phase current, B-phase current, and C-phase current of the rotor of the doubly-fed asynchronous motor. This refers to the short-circuit current in the inter-turn short-circuit loop. The construction of stator and rotor flux linkage residual vectors under different fault phase conditions in a three-phase coordinate system includes: The stator flux residues under different fault phase conditions are set as follows: ； The rotor flux residues under different fault phase conditions are as follows: ； Therefore, the stator flux residue is calculated as follows when phase A fails: ； In the formula, For short-circuit ratio, For stator winding resistance, This is the short-circuit current. For magnetizing inductance, This refers to the mutual inductance between the stator winding and the rotor winding; The rotor flux linkage residual is calculated as follows: ； In the formula, The angle between the axis of rotor phase a winding and the axis of stator phase A winding; When phase B fails, the stator flux residue is calculated as follows: ； The rotor flux linkage residual is calculated as follows: ； When a C-phase fault occurs, the stator flux residue is calculated as follows: ； The rotor flux linkage residual is calculated as follows: ； The short-circuit loop flux residual is set to be under different fault phase conditions. ; When phase A is faulted, the short-circuit loop flux residue is as follows: ； When a phase B fault is assumed, the short-circuit loop flux residual is as follows: ； When a phase C fault is assumed, the short-circuit loop flux residue is as follows: 。 2. The method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor according to claim 1, characterized in that, The construction of the second doubly-fed asynchronous motor flux linkage calculation model includes: The flux linkage of the doubly-fed asynchronous motor is calculated using the flux linkage equation. Magnetic Link The definition is as follows: , The calculation satisfies the following relationship: ； In the formula, The inductance matrix of the doubly-fed asynchronous motor satisfies the following relationship: ； In the formula, For the inductor submatrix, and Let be the self-inductance matrix. and For mutual inductance matrix, The mutual inductance coefficient between the normal portion of the stator X-phase winding and the short-circuit circuit after the fault is given by, where, , This is the self-inductance of the short-circuit loop.

3. The method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor according to claim 1, characterized in that, The determination of the flux linkage residual includes: The flux linkage residual is defined as follows: ； in, The calculation formula is as follows: ； In the formula, For the first doubly-fed asynchronous motor flux linkage, For the second doubly-fed asynchronous motor flux linkage, The resistance matrix is ​​obtained by subtracting the voltage equations under normal and fault conditions. The current matrix is ​​obtained by subtracting the current under normal and fault conditions. This is the inductance matrix.

4. The method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor according to claim 1, characterized in that, The fault detection based on the amplitude and threshold of the flux linkage residual includes: Set an adaptive threshold T for fault diagnosis that satisfies the following relationship: ； Define fault diagnosis variables It satisfies the following relationship: ； In the formula, The flux linkage residual vector is... The sliding average value is represented by a sliding window time of one phase current cycle. Based on fault diagnosis variables and adaptive fault diagnosis thresholds, the determination of whether a fault has occurred satisfies the following relationship: ； In the formula, This is the result of fault diagnosis.

5. The method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor according to claim 1, characterized in that, The stator and rotor flux linkage residual vectors under different fault phase conditions in the three-phase coordinate system are transformed to... In a coordinate system, including: set up When phase A is faulted in the coordinate system, the residual vector is as follows: ； When phase B fails, the residual vector is as follows: ； During a C-phase fault, the residual vector is as follows: 。 6. The method for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor according to claim 1, characterized in that, The fault location phase includes: Sure The vector angle K of the flux linkage residual in the coordinate system is as follows: ； In the formula, and For the stator flux linkage residual vector in Components in coordinate system Components in the coordinate system; according to The vector angle K of the flux linkage residual in the coordinate system locates the fault phase, as follows: When K = 0, it indicates a phase A fault; when K = -π / 3, it indicates a phase B fault; and when K = π / 3, it indicates a phase C fault.

7. A system for diagnosing inter-turn short-circuit faults in the stator winding of a doubly-fed asynchronous motor, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1-6.

Images