Dual three-phase permanent magnet synchronous motor winding fault diagnosis and positioning method

Abstract

The invention specifically relates to a dual three-phase permanent magnet synchronous motor winding fault diagnosis and positioning method, and belongs to the technical field of motor fault diagnosis. Comprising the following steps: firstly, collecting armature current and carrying out clark conversion to obtain current components of planes of two sets of windings, calculating a current difference value of the corresponding component, extracting a half-cycle effective value as a fault diagnosis characteristic, and calculating a phase angle of a current vector as a fault positioning characteristic; the method provided by the invention can diagnose whether the winding has a fault on line and determine the type and position of the fault. The method disclosed by the invention is of great significance for improving the operation reliability and the maintenance convenience of the dual three-phase permanent magnet synchronous motor.

Description

Technical Field

[0001] This invention relates to the field of motor fault diagnosis technology, specifically to a method based on armature current. A method for fault diagnosis and location of windings in a dual-phase three-phase permanent magnet synchronous motor based on planar current difference and phase characteristics. Background Technology

[0002] With the development of the aviation industry, aircraft are showing a trend towards multi-electrification and full electrification, and traditional secondary energy drive systems such as hydraulic and pneumatic systems are gradually being replaced by electric drive systems. As a key component of the aviation electric actuation system, the performance of the electric motor directly affects the aircraft's performance; therefore, the research and breakthroughs in aviation electric motors are of paramount importance.

[0003] Due to the special operating conditions, such as high-altitude operation, and especially in applications involving aircraft electrical systems, environmental control systems, and flight control systems, aviation motors face extremely high requirements for component reliability and continued operation under fault conditions. In these high-reliability applications, traditional three-phase motors, limited by the number of winding phases, often have to shut down when one or two phases experience an open-circuit or short-circuit fault. In contrast, dual three-phase permanent magnet synchronous motors, with their multi-phase redundancy, can continue operating by switching to a fault-tolerant control strategy in the event of a fault, exhibiting excellent fault tolerance and significant potential in the field of aviation electric actuation systems.

[0004] Among the faults of dual three-phase permanent magnet synchronous motors, open circuit in the motor windings and inter-turn short circuit faults are relatively common electrical faults, such as... Figure 1 The diagram shows the winding structure and fault types of a dual three-phase permanent magnet synchronous motor. If a fault is not diagnosed and handled promptly and accurately, it may cause further damage to the motor or even pose a serious threat to the entire system. Therefore, fault diagnosis strategies have become an indispensable part of ensuring the safe and stable operation of dual three-phase permanent magnet synchronous motors.

[0005] To improve the fault tolerance and operational reliability of dual three-phase permanent magnet synchronous motors, the health status of the motors is monitored in real time to diagnose whether open circuit faults or inter-turn short circuit faults have occurred in the motor windings. In addition to determining the type of fault, it is also necessary to diagnose the location of the fault so that appropriate measures can be taken after the fault occurs. This is called the fault diagnosis and location method for dual three-phase permanent magnet synchronous motor windings.

[0006] Current diagnostic methods for open-circuit faults and inter-turn short-circuit faults in the windings of dual three-phase permanent magnet synchronous motors are mostly designed for diagnosing and locating one type of fault, with few methods capable of simultaneously diagnosing and locating both types. This invention proposes a method based on armature current... A method for fault diagnosis and location of windings in a dual-phase three-phase permanent magnet synchronous motor based on planar current difference and phase characteristics. The proposed method can simultaneously distinguish the characteristics of open circuit faults and inter-turn short circuit faults (including single-phase short circuit faults) in the windings of a dual-phase three-phase permanent magnet synchronous motor, thereby determining the fault type and locating the fault location.

[0007] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0008] To address the challenge of similar fault characteristics (phase current imbalance leading to increased harmonic current) caused by open-circuit faults and inter-turn short-circuit faults in the windings of dual three-phase permanent magnet synchronous motors, this invention provides a method based on armature current... A method for fault diagnosis and location of windings in a dual-three-phase permanent magnet synchronous motor based on planar current difference and phase characteristics can diagnose open-circuit faults and inter-turn short-circuit faults (including single-phase short circuits) without relying on motor parameters or being affected by motor operating conditions, and simultaneously determine the specific location of the fault.

[0009] Other features and advantages of the invention will become apparent from the following detailed description, or may be learned in part by practice of the invention.

[0010] According to a first aspect of the present invention, a method for diagnosing and locating winding faults in a dual three-phase permanent magnet synchronous motor is provided, the method comprising: Step S1: Armature current signal acquisition The armature currents of the two sets of three-phase symmetrical windings of the dual three-phase permanent magnet synchronous motor are collected and denoted as follows: and ; respectively and Perform a Clark transformation to obtain the result corresponding to the first set of windings. Plane current distribution and corresponding to the second set of windings Plane current components ; Step S2: Preliminary diagnosis of motor winding faults Calculate the corresponding windings of the two sets of windings The difference between the plane current components yields the difference current. and The sliding window method is used to calculate the time within half a period. and effective value and Set the first threshold thr1, if and If all values ​​are less than or equal to thr1, the motor is considered to be in a healthy state, and the process returns to step S1; if... or If the value is greater than thr1, the motor is determined to be faulty, and the process proceeds to step S3. Step S3: Fault Type Determination According to the current component Calculate the first set of windings Angle of plane current vector And according to the current components Calculate the second set of windings Angle of plane current vector ; Angle Adjust to the interval respectively Within; a sliding window mode is used to calculate the value within half a period. average The sum of variance S1 and the variance within half a period average S1 and S2; set a second threshold thr2. If either S1 or S2 is less than or equal to thr2, it is determined to be an open circuit fault and proceeds to step S4; if both S1 and S2 are greater than thr2, it is determined to be an inter-turn short circuit fault and proceeds to step S5. Step S4: Determine the location of the open circuit fault Based on the variances S1, S2, and mean calculated in step S3 , Identify the specific faulty phase; Step S5: Determining the location of the inter-turn short circuit fault Based on the differential current and Calculate the angle of the differential current vector and angle Adjust to range Inside; the interval Divide the data into six sub-intervals on average; statistically analyze the angles within one period. The proportion of data points falling in each sub-interval; the phase corresponding to the sub-interval with the largest proportion is determined as the inter-turn short-circuit fault phase.

[0011] In some exemplary embodiments, in step S2, the value range of the first threshold thr1 is (0, 0.05 * I). N ), I N This refers to the rated current of the motor.

[0012] In some exemplary embodiments, in step S3, the value range of the second threshold thr2 is (0, 0.3).

[0013] In some exemplary embodiments, step S4 specifically includes: like Then the faulty phase is determined to be located in the first winding ABC, and based on the average value... Identify the specific faulty phase: like exist In the interval, the faulty phase is phase A; like exist In the interval, the faulty phase is phase B; like exist In the interval, the faulty phase is phase C; when At that time, the faulty phase was determined to be in the second set of windings XYZ, and according to... The specific faulty phase is determined as follows: like exist If the faulty phase is within the interval, then the faulty phase is phase X.

[0014] like exist In the interval, the faulty phase is phase Y.

[0015] like exist or In the interval, the faulty phase is phase Z.

[0016] In some exemplary embodiments, in step S5, the interval The average division into six sub-intervals is as follows: Region S1 is and S2 is S3 is S4 is S5 is S6 is .

[0017] In some exemplary embodiments, the angle is statistically analyzed over a period of time. The proportion of data points whose values ​​fall within each sub-interval; the phase corresponding to the sub-interval with the largest proportion is determined as the inter-turn short-circuit fault phase, specifically: Calculate the angle within one period The proportion of data points whose values ​​fall within sub-intervals S1, S2, S3, S4, S5, and S6 is denoted as T1, T2, T3, T4, T5, and T6. Find the maximum value among T1 to T6, and make a judgment based on the maximum value, specifically: When the maximum value is T1, the faulty phase is phase A; When the maximum value is T2, the faulty phase is phase B; When the maximum value is T3, the faulty phase is phase C; When the maximum value is T4, the faulty phase is phase X; When the maximum value is T5, the faulty phase is phase Y; When the maximum value is T6, the faulty phase is phase Z.

[0018] In some exemplary embodiments, the angle adjustment method in steps 3 and 5 is as follows: when the calculated angle value is within the range At that time, by adding π to the angle value, it is adjusted to the range. Inside.

[0019] The embodiments of the present invention provide armature current-based... A method for fault diagnosis and location of windings in a dual-phase three-phase permanent magnet synchronous motor (PMSM) based on planar current difference and phase characteristics is proposed. This method enables online diagnosis of winding faults during motor operation, distinguishing between open-circuit faults and inter-turn short-circuit faults, and pinpointing the specific location of the fault. The proposed method is independent of motor parameters and unaffected by motor operating conditions, thus improving the operational reliability and maintenance convenience of the dual-phase three-phase PMSM.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0022] Figure 1 This is a schematic diagram of the winding structure and fault types of a dual three-phase permanent magnet synchronous motor. Figure 2 The proposed approach for fault diagnosis of windings in dual three-phase permanent magnet synchronous motors; Figure 3 A flowchart of a method for fault diagnosis and fault type determination of windings in a dual three-phase permanent magnet synchronous motor; Figure 4 A flowchart illustrating a method for determining the location of winding faults in a dual three-phase permanent magnet synchronous motor. Figure 5 These are characteristic quantities under operating condition 1; Figure 6 These are characteristic quantities under operating condition 2; Figure 7 These are characteristic quantities under operating condition 3; Figure 8 This is a characteristic quantity under operating condition 4. Detailed Implementation

[0023] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the invention will be more comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0024] Furthermore, the accompanying drawings are merely illustrative of the invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0025] A method based on armature current An online diagnosis and location method for winding faults in a dual-three-phase permanent magnet synchronous motor based on plane current difference and phase characteristics. This method targets the six-phase windings of a dual-three-phase permanent magnet synchronous motor. When an open-circuit fault or inter-turn short-circuit fault occurs in the motor, it is based on the armature current... Planar current signals enable rapid and accurate fault diagnosis, determining the fault type and location. The structure of the dual three-phase permanent magnet synchronous motor is as follows: Figure 1 As shown, the motor armature winding consists of two sets of three-phase symmetrical windings: the ABC three-phase winding and the XYZ three-phase winding. Both sets of three-phase windings are connected in a star configuration, with a spatial layout that differs from each other by 30° electrical degrees. The neutral points of the two sets of windings are independent of each other.

[0026] The steps of the online diagnosis and location method for winding faults in a dual three-phase permanent magnet synchronous motor are as follows: Step 1: Armature Current Signal Acquisition. The armature current of the dual three-phase permanent magnet synchronous motor is acquired using a current sensor and denoted as... and , respectively and Perform Clark transform to obtain and .

[0027] Step 2: Preliminary diagnosis of motor winding faults. The obtained... and First calculate and The sliding window method is used to calculate the value within half a period. and effective value and The threshold value thr1 ranges from 0 to 0.05*I. N ), I N This refers to the rated current of the motor. According to... , Preliminary fault diagnosis of the windings of a dual three-phase permanent magnet synchronous motor is performed using the threshold value thr1 to determine whether a fault has occurred in the motor. Specifically: (1) If If the windings of the dual three-phase permanent magnet synchronous motor are determined to be in good condition and without fault, proceed to step 1.

[0028] (2) If To determine if a fault has occurred in the windings of the dual three-phase permanent magnet synchronous motor, proceed to step 3.

[0029] Step 3: Fault type determination. Based on... and Calculate each The angle of the plane current vector is calculated using the following formula: ,when exist At that time, by giving By adding π, Adjust to The interval is then calculated using a sliding window method within half a period. The average value is denoted as and Simultaneously, a sliding window mode is used to calculate the time within half a cycle. The variances are denoted as S1 and S2. The threshold thr2 ranges from 0 to 0.3. Based on S1, S2, and the threshold thr2, the fault types of the windings of the dual-phase three-phase permanent magnet synchronous motor are distinguished as follows: (1) If If an open circuit fault is detected in the stator winding of the dual three-phase permanent magnet synchronous motor, proceed to step 4.

[0030] (2) If If a short-circuit fault is detected in the stator winding of the dual three-phase permanent magnet synchronous motor, proceed to step 5.

[0031] Step 4: Determine the location of the open circuit fault. Based on S1, S2, and... calculated in Step 3... , To determine the location of the fault. When At that time, the faulty phase was determined to be in the first set of windings ABC, and according to... The specific faulty phase is determined as follows: (1) If exist If the faulty phase is within the interval, then the faulty phase is phase A.

[0032] (2) If exist If the faulty phase is within the interval, then the faulty phase is phase B.

[0033] (3) If exist In the interval, the faulty phase is phase C.

[0034] when At that time, the faulty phase was determined to be in the second set of windings XYZ, and according to... The specific faulty phase is determined as follows: (1) If exist If the faulty phase is within the interval, then the faulty phase is phase X.

[0035] (2) If exist In the interval, the faulty phase is phase Y.

[0036] (3) If exist or In the interval, the faulty phase is phase Z.

[0037] Step 5: Determine the location of the inter-turn short-circuit fault. Based on... and calculate ,when exist At that time, by giving By adding π, Adjust to The interval. Divided into 6 regions on average, region S1 is and S2 is S3 is S4 is S5 is S6 is Calculate within a period The proportion of data points in each region to the total number of data points is denoted as T1, T2, T3, T4, T5, and T6. The maximum value among T1 to T6 is obtained, and a judgment is made based on this maximum value, specifically: (1) When the maximum value is T1, the faulty phase is phase A.

[0038] (2) When the maximum value is T2, the faulty phase is phase B.

[0039] (3) When the maximum value is T3, the faulty phase is phase C.

[0040] (4) When the maximum value is T4, the faulty phase is phase X.

[0041] (5) When the maximum value is T5, the faulty phase is the Y phase.

[0042] (6) When the maximum value is T6, the faulty phase is phase Z.

[0043] Figure 4 A flowchart of a method for fault diagnosis and fault type determination of windings in a dual three-phase permanent magnet synchronous motor; Figure 5 This is a block diagram of the method for determining the fault location of a dual three-phase permanent magnet synchronous motor winding proposed in this invention. Figure 4 and Figure 5 The proposed method constitutes the fault diagnosis and location method for the windings of a dual three-phase permanent magnet synchronous motor proposed in this invention. The invention is further described below with reference to the accompanying drawings and embodiments, which include, but are not limited to, the following embodiments.

[0044] The embodiment establishes a simulation model for simulating open-circuit faults and inter-turn short-circuit faults in the windings of a dual three-phase permanent magnet synchronous motor. The embodiment includes the dual three-phase permanent magnet synchronous motor structure and fault simulation methods as follows: Figure 1 As shown, both sets of three-phase windings are connected in a star configuration, with a spatial layout that differs from each other by 30° electrical angle, and the neutral points of the two sets of windings are independent of each other.

[0045] The motor employs vector space decoupling control. The dq plane uses dual closed-loop PI control for speed and current, while the harmonic plane uses PI control. The load is 0.35 Nm (rated 0.7 Nm), and the motor speed is 2000 r / min (rated 4000 r / min). At this speed, the current frequency is 166.7 Hz. The simulation step size is set to 1e-06, and the sampling points per cycle are... The sampling points for half a cycle are Simulations were performed for the following four operating conditions: (1) The motor starts working in good condition, and an open circuit fault occurs in phase A winding 0.5 seconds later; (2) The motor starts working in good condition, and an open circuit fault occurs in the X phase winding 0.5 seconds later; (3) The motor starts working in good condition. After 0.5 seconds, an inter-turn short circuit fault occurs in the A-phase winding with a short circuit coefficient of 0.35. (4) The motor starts working in good condition. After 0.5 seconds, an inter-turn short circuit fault occurs in the C-phase winding with a short circuit coefficient of 0.35. Step 1: Armature Current Signal Acquisition. The armature current of the dual three-phase permanent magnet synchronous motor is acquired using a current sensor and denoted as... and , respectively and Perform the CLRAK transform to obtain and . Step 2: Preliminary diagnosis of motor winding faults. The obtained... and First calculate and The sliding window method is used to calculate the value within half a cycle. and effective value and The calculation formula is: , ,according to and Preliminary fault diagnosis of the windings of a dual three-phase permanent magnet synchronous motor was performed to determine whether a fault had occurred. The threshold thr1 was set to 0.02, and the simulation results are as follows. Figure 5-8 As shown: Operating Condition 1 (From healthy state to open circuit fault in phase A winding): In the healthy state, and The value is essentially zero, less than the threshold thr1; after a fault occurs after 0.5 seconds, Approximately 1, Approximately 0.005, If the value is greater than thr1, it is diagnosed as a fault, and step 3 is performed.

[0046] Operating Condition 2 (From Healthy State to Open Circuit Fault in Phase X Winding): In the healthy state, and The value is essentially zero, less than the threshold thr1; after a fault occurs after 0.5 seconds, Approximately 0.75 The value is approximately 0.25, which is greater than thr1. This is diagnosed as a fault, and step 3 is performed.

[0047] Operating condition 3 (from healthy state to inter-turn short circuit fault in phase A winding): In the healthy state, and The value is essentially zero, less than the threshold thr1; after a fault occurs after 0.5 seconds, Approximately 0.04 Approximately 0.01, If the value is greater than thr1, it is diagnosed as a fault, and step 3 is performed.

[0048] Operating condition 4 (from healthy state to inter-turn short circuit fault in phase C winding): In the healthy state, and The value is essentially zero, less than the threshold thr1; after a fault occurs after 0.5 seconds, Approximately 0.025 The value is approximately 0.04, which is greater than thr1. This is diagnosed as a fault, and step 3 is performed.

[0049] Step 3: Fault type determination. Based on... and Calculate each The angle of a plane current vector, calculation formula ,when exist At that time, by giving By adding π, Adjust to The interval is defined, and then a sliding window mode is used to calculate the interval within half a period. The average value is denoted as and The calculation formula is: , Simultaneously, a sliding window mode is used to calculate the time within half a cycle. The variances, denoted as S1 and S2, are calculated using the following formula: , The threshold thr2 is set to 0.05, and the fault types of the windings of the dual three-phase permanent magnet synchronous motor are distinguished based on S1, S2 and the threshold thr2.

[0050] Condition 1 (from healthy state to open circuit fault in phase A winding): S1 is 0, which is less than thr2, S2 is 0.8, which is greater than thr2, an open circuit fault occurs, proceed to step 4.

[0051] Condition 2 (from healthy state to open circuit fault in X phase winding): S1 is about 0.8, which is greater than thr2, and S2 is zero, which is less than thr2. An open circuit fault occurs, and step 4 is performed.

[0052] Condition 3 (from healthy state to inter-turn short circuit fault in phase A winding): S1 is about 0.95, which is greater than thr2, and S2 is about 0.8, which is greater than thr2. An inter-turn short circuit fault occurs, and step 5 is performed.

[0053] Condition 4 (from healthy state to inter-turn short circuit fault in phase C winding): S1 is approximately 0.69, which is greater than thr2, and S2 is approximately 0.77, which is greater than thr2. An inter-turn short circuit fault occurs, and step 5 is performed.

[0054] Step 4: Determine the location of the open circuit fault. Based on S1, S2, and... calculated in Step 3... , To determine the location of the fault. When At that time, according to Determine the specific faulty phase in the first set of windings (A, B, and C phases). At that time, according to Identify the specific faulty phase in the XYZ phases of the second winding.

[0055] Operating condition 1 (from healthy state to open circuit fault in phase A winding): At this time , Approximately π / 2, in Within the interval, it is determined that an open-circuit fault has occurred in phase A winding.

[0056] Operating Condition 2 (From healthy state to open circuit fault in phase X winding): At this time , Approximately 2*π / 3, in Within the interval, it is determined that an open-circuit fault has occurred in the X-phase winding.

[0057] Step 5: Determine the location of the inter-turn short-circuit fault. Based on... and calculate ,when exist At that time, by giving By adding π, Adjust to The interval. Divided into 6 regions on average, region S1 is and S2 is S3 is S4 is S5 is S6 is Calculate within a period The proportion of data points in each region to the total number of data points is denoted as T1, T2, T3, T4, T5, and T6. The maximum value is obtained, and a judgment is made based on the maximum value, specifically: Operating condition 3 (from healthy state to inter-turn short circuit fault in phase A winding): 0.5 seconds later, Most of the data points are located in ,and At this point, T1 is at its maximum, and the diagnosis is an inter-turn short circuit fault in phase A winding.

[0058] Operating condition 4 (from healthy state to inter-turn short circuit fault in phase C winding): 0.5 seconds later, Most of the data points are located in At this point, T3 is at its maximum, and the diagnosis is an inter-turn short circuit fault in the C-phase winding.

[0059] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

[0060] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is defined only by the appended claims.

Claims

1. A method for fault diagnosis and location of a double three-phase permanent magnet synchronous motor winding, characterized in that, The method includes: Step S1: Armature current signal acquisition The armature currents of the two sets of three-phase symmetrical windings of the dual three-phase permanent magnet synchronous motor are collected and denoted as follows: and ; respectively and Perform a Clark transformation to obtain the result corresponding to the first set of windings. Plane current division and corresponding to the second set of windings Plane current components ; Step S2: Preliminary diagnosis of motor winding faults Calculate the corresponding windings of the two sets of windings The difference between the plane current components yields the difference current. and The sliding window method is used to calculate the time within half a period. and effective value and Set the first threshold thr1, if and If all values ​​are less than or equal to thr1, the motor is considered to be in a healthy state, and the process returns to step S1; if... or If the value is greater than thr1, the motor is determined to be faulty, and the process proceeds to step S3. Step S3: Fault Type Determination According to the current component Calculate the first set of windings Angle of plane current vector And based on the current components Calculate the second set of windings Angle of plane current vector ; Angle Adjust to the interval respectively Within; a sliding window mode is used to calculate the value within half a period. average The sum of variance S1 and the variance within half a period average S1 and S2; set a second threshold thr2. If either S1 or S2 is less than or equal to thr2, it is determined to be an open circuit fault and proceeds to step S4; if both S1 and S2 are greater than thr2, it is determined to be an inter-turn short circuit fault and proceeds to step S5. Step S4: Determine the location of the open circuit fault Based on the variances S1, S2, and mean calculated in step S3 , Identify the specific faulty phase; Step S5: Determining the location of the inter-turn short circuit fault Based on the differential current and Calculate the angle of the differential current vector and angle Adjust to range Inside; the interval Divide the data into six sub-intervals on average; statistically analyze the angles within one period. The proportion of data points falling in each sub-interval; the phase corresponding to the sub-interval with the largest proportion is determined as the inter-turn short-circuit fault phase.

2. The method according to claim 1, characterized in that, In step S2, the first threshold thr1 has a value range (0, 0.05*I N ), I N is the rated current of the motor.

3. The method according to claim 1, characterized in that, In step S3, the value range of the second threshold thr2 is (0, 0.3).

4. The method according to claim 1, characterized in that, Step S4 specifically includes: like Then the faulty phase is determined to be located in the first winding ABC, and based on the average value... Identify the specific faulty phase: like exist In the interval, the faulty phase is phase A; like exist In the interval, the faulty phase is phase B; like exist In the interval, the faulty phase is phase C; when At that time, the faulty phase was determined to be in the second set of windings XYZ, and according to... The specific faulty phase is determined as follows: like exist If the faulty phase is within the interval, then the faulty phase is phase X. like exist In the interval, the faulty phase is phase Y. like exist or In the interval, the faulty phase is phase Z.

5. The method according to claim 1, characterized in that, In step S5, the interval The average division into six sub-intervals is as follows: Region S1 is and S2 is S3 is S4 is S5 is S6 is .

6. The method according to claim 5, characterized in that, The angle within a statistical period The proportion of data points whose values ​​fall within each sub-interval; the phase corresponding to the sub-interval with the largest proportion is determined as the inter-turn short-circuit fault phase, specifically: Calculate the angle within one period The proportion of data points whose values ​​fall within sub-intervals S1, S2, S3, S4, S5, and S6 is denoted as T1, T2, T3, T4, T5, and T6. Find the maximum value among T1 to T6, and make a judgment based on the maximum value, specifically: When the maximum value is T1, the faulty phase is phase A; When the maximum value is T2, the faulty phase is phase B; When the maximum value is T3, the faulty phase is phase C; When the maximum value is T4, the faulty phase is phase X; When the maximum value is T5, the faulty phase is phase Y; When the maximum value is T6, the faulty phase is phase Z.

7. The method according to claim 1, characterized in that, The angle adjustment method in steps 3 and 5 is as follows: when the calculated angle value is within the range At that time, by adding π to the angle value, it is adjusted to the range. Inside.

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