A method for rapid calculation of equivalent circuit parameters of a high-capacity AC excitation motor

Abstract

This invention discloses a rapid calculation method for equivalent circuit parameters of a high-capacity AC excitation motor, belonging to the field of motor parameter calculation. Starting from the motor's magnetic flux path and characteristics, this method divides the stator and rotor leakage inductance into stator and rotor slot leakage inductance, stator and rotor harmonic leakage inductance, stator and rotor end leakage inductance, and stator and rotor tooth tip leakage inductance. For each magnetic flux path, the four parts of leakage inductance are calculated precisely. It fully utilizes information such as flux linkage and magnetic energy storage obtained from static field simulations to calculate motor parameters. Only three static field simulations are needed to calculate all motor parameters. Compared to conventional parameter calculation methods based on transient fields, this method improves the parameter calculation efficiency for this type of motor and helps shorten the design cycle of high-capacity AC excitation motors.

Description

Technical Field

[0001] This invention belongs to the field of motor parameter calculation, and more specifically, relates to a method for rapid calculation of equivalent circuit parameters of a large-capacity AC excitation motor. Background Technology

[0002] The equivalent circuit parameters of large-capacity AC excitation motors directly affect their power regulation range and response speed to the power grid. Therefore, new power systems place higher demands on the accuracy of parameter design for large-capacity AC excitation motors. Current parameter calculation methods mainly refer to synchronous motors of the same capacity, megawatt-class doubly-fed wind turbines, or large asynchronous motors. However, large-capacity AC excitation motors experience frequent operating condition changes, wide speed ranges, and large slot current variations, causing their equivalent circuit parameters to change within the speed range. This makes it difficult for conventional analytical algorithms or empirical formulas to accurately calculate the equivalent circuit parameters of large-capacity AC excitation motors under all operating conditions.

[0003] Existing finite element method (FEM) parameter calculation methods require multiple transient simulations and complex post-processing to obtain accurate motor parameters, significantly reducing motor design efficiency. Other methods separately calculate stator and rotor leakage inductance, but these methods either neglect harmonic leakage inductance or tooth tip leakage inductance. Both methods that ignore slot leakage inductance and tooth tip leakage inductance suffer from insufficient calculation accuracy, and none of these methods are suitable for applications requiring simultaneous calculation of harmonic and tooth tip leakage inductance. The generality of this type of method is insufficient; some parameter calculation methods first calculate the total leakage inductance, and then subtract the sum of slot leakage inductance, harmonic leakage inductance, and end leakage inductance to obtain the tooth tip leakage inductance. This type of method calculates all leakage inductance parameters, but the calculation accuracy of the tooth tip leakage inductance is affected by the calculation accuracy of other leakage inductance parameters. If the calculated value of the total leakage inductance is larger than the true value, and the calculated values ​​of other leakage inductance are smaller than the true values, this will lead to a larger deviation between the calculated value of the tooth tip leakage inductance and the true value. Therefore, this type of method cannot meet the calculation accuracy requirements of the equivalent circuit parameters of large-capacity AC excitation motors. Summary of the Invention

[0004] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a rapid calculation method for the equivalent circuit parameters of a large-capacity AC excitation motor. This method helps improve the design efficiency and parameter accuracy of large-capacity AC excitation motors, and facilitates the full utilization of the supporting role of large-capacity AC excitation motors in new power systems.

[0005] To achieve the above objectives, according to a first aspect of the present invention, a method for rapidly calculating the equivalent circuit parameters of a large-capacity AC excitation motor is provided, comprising:

[0006] S1, the stator leakage inductance and rotor leakage inductance of the motor are divided into slot leakage inductance, harmonic leakage inductance, tooth tip leakage inductance and end leakage inductance; wherein, the equivalent circuit parameters of the motor include magnetizing inductance, stator leakage inductance and rotor leakage inductance;

[0007] S2, Select the corresponding end leakage inductance calculation formula according to the end winding shape of the motor to calculate the end leakage inductance of the stator and rotor;

[0008] S3, establish a first simulation model of the motor in the finite element software, run the first simulation model under rated operating conditions using the static magnetic field simulation technology of the finite element software, and save the stator permeability and rotor permeability in the first simulation model, as well as the radial magnetic flux density entering the teeth of the stator and rotor.

[0009] S4, calculate the excitation inductance and harmonic leakage inductance of the stator and rotor based on the radial magnetic flux density of the teeth of the stator and rotor;

[0010] S5. Establish a second simulation model of the motor in the finite element software, set its stator permeability to the stator permeability in S3, and set its stator three-phase current. I A , I B , I C The rotor permeability was set to infinitesimal and the rotor current to 0. The second simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the stator slots and the magnetic energy stored in the air gap. W ssl and W sgl According to the formula , Calculate stator slot leakage inductance and stator tooth tip leakage inductance L ssl and L sgl ;

[0011] A third simulation model of the motor is established in the finite element software, and its rotor permeability is set to the rotor permeability in S3. The rotor three-phase current is also set. I U , I V , I W The stator permeability was set to infinitesimal and the stator current to 0. The third simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the rotor slots and the magnetic energy stored in the air gap. W rsl and W rgl According to the formula , Calculate rotor slot leakage inductance and rotor tooth tip leakage inductance L rsl and L rgl .

[0012] According to a second aspect of the present invention, an electronic device is provided, comprising: a computer-readable storage medium and a processor;

[0013] The computer-readable storage medium is used to store executable instructions;

[0014] The processor is configured to read executable instructions stored in the computer-readable storage medium and execute the method as described in the first aspect.

[0015] According to a third aspect of the invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to perform the method as described in the first aspect.

[0016] According to a fourth aspect of the invention, a computer program product is provided, comprising a computer program or instructions that, when executed by a processor, implement the method described in the first aspect.

[0017] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0018] To address the problems of low computational efficiency and insufficient accuracy in existing methods for calculating the equivalent circuit parameters of large-capacity AC excitation motors, this invention provides a rapid calculation method for the equivalent circuit parameters of large-capacity AC excitation motors. This method starts from the motor's magnetic flux path and characteristics, dividing the stator and rotor leakage inductance into stator and rotor slot leakage inductance, stator and rotor harmonic leakage inductance, stator and rotor end leakage inductance, and stator and rotor tooth tip leakage inductance. For each type of magnetic flux path, the leakage inductance of these four parts is calculated precisely. Considering that the slot leakage flux of the motor stator and rotor only passes through the stator and rotor slots, and that most of the tooth tip leakage flux only passes through the air gap, the energy in the stator and rotor slots and the energy in the air gap are calculated separately to obtain the stator and rotor slot leakage inductance and the stator and rotor tooth tip leakage inductance respectively. Considering that both harmonic flux linkages and main flux linkages radially penetrate the stator and rotor teeth, the harmonic flux linkages penetrating the iron core are calculated based on the flux linkage method. The flux linkage and main flux linkage are then used to obtain the stator and rotor harmonic leakage inductance and excitation inductance, respectively. Considering that the calculation formula for end leakage inductance is now relatively mature, the empirical formula for end leakage inductance that conforms to the shape of the stator and rotor winding ends is selected to obtain the end leakage inductance, which has both high calculation accuracy and faster calculation speed. In addition, in the process of calculating the above parameters, the frozen permeability function in the static field finite element simulation technology is used to ensure that the permeability during parameter calculation is consistent with the permeability under the required operating conditions, so that this method can consider the nonlinear changes in parameters caused by core saturation. Compared with the conventional finite element parameter calculation method, only 3 static field finite element simulations are needed to obtain all inductance parameters of the equivalent circuit of the large-capacity AC excitation motor and complete the extraction calculation of all leakage inductance, which greatly improves the parameter calculation efficiency of this type of motor and helps to shorten the design cycle of the large-capacity AC excitation motor.

[0019] In summary, the method provided by this invention calculates the leakage inductance of each part of the magnetic flux based on its specific path and characteristics, thus accurately calculating the leakage inductance of each part of the stator and rotor, achieving higher accuracy compared to existing parameter calculation methods. Furthermore, this invention fully utilizes information such as flux linkage and magnetic energy storage obtained from static field simulations to calculate motor parameters, requiring only three static field simulations to calculate all motor parameters, which improves the efficiency of parameter acquisition compared to conventional parameter calculation methods based on transient fields. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the method for rapid calculation of equivalent circuit parameters of a large-capacity AC excitation motor provided in an embodiment of the present invention.

[0021] Figure 2 This is a detailed inductance model of a high-capacity AC excitation motor provided in the embodiments of the present invention;

[0022] Figure 3 This is a magnetic field distribution diagram of stator slot leakage inductance and stator tooth tip leakage inductance provided in an embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] This invention provides a method for rapidly calculating the equivalent circuit parameters of a large-capacity AC excitation motor, such as... Figure 1 As shown, it includes:

[0025] S1, the stator leakage inductance and rotor leakage inductance of the motor are divided into slot leakage inductance, harmonic leakage inductance, tooth tip leakage inductance and end leakage inductance; wherein, the equivalent circuit parameters of the motor include magnetizing inductance, stator leakage inductance and rotor leakage inductance.

[0026] Specifically, based on the equivalent circuit of a large-capacity AC excitation motor, a detailed inductance model of the large-capacity AC excitation motor is established: Ignoring the stator and rotor resistances, the stator leakage inductance and rotor leakage inductance are further subdivided. The stator leakage inductance is divided into slot leakage inductance, harmonic leakage inductance, tooth tip leakage inductance, and end leakage inductance. Similarly, the rotor leakage inductance is divided into slot leakage inductance, harmonic leakage inductance, tooth tip leakage inductance, and end leakage inductance. The detailed inductance model is as follows: Figure 2 As shown.

[0027] Figure 2 middle, U s , E 0、 ω and ω represent the stator voltage, back EMF, rotor voltage referred to the stator side, and stator angular frequency, respectively. L se , L ssl , L shl and L sgl These represent the stator end leakage inductance, stator slot leakage inductance, stator harmonic leakage inductance, and stator tooth tip leakage inductance, respectively. L m Indicates the magnetizing inductance. , , and These represent the rotor end leakage inductance, rotor slot leakage inductance, rotor harmonic leakage inductance, and rotor tooth tip leakage inductance referred to the stator side, respectively. These referred values ​​have the following relationship with the rotor leakage inductance parameters calculated in this invention.

[0028]

[0029] in express Figure 2 The rotor leakage inductance value in the middle, L This represents the rotor leakage reactance value calculated in this invention. K w1 and K w2 These represent the stator winding coefficient and the rotor winding coefficient, respectively. N 1 and N 2 represents the number of turns in series per phase of the stator and the number of turns in series per phase of the rotor, respectively.

[0030] S2, Select the corresponding end leakage inductance calculation formula according to the end winding shape of the motor to calculate the end leakage inductance of the stator and rotor.

[0031] Specifically, the end leakage inductance of the stator and rotor of a large-capacity AC excitation motor is calculated using analytical calculation formulas.

[0032] Based on the stator end winding shape of a high-capacity AC excitation motor, select an analytical calculation formula that matches the motor's end shape. For example, the following calculation formula can be used for double-layer lap windings or wave windings:

[0033]

[0034] in, L se For stator end leakage inductance, N 1 and K w1 The number of series turns per phase of the stator and the stator winding coefficient, p For extreme logarithms, A 1 represents the straight length of the stator winding extending from its end. M 1 represents the axial projection length of the stator end winding.

[0035] The rotor of a high-capacity AC excitation motor is a wound-rotor type. Therefore, the connection method of the rotor winding and the shape of the end windings are similar to those of the stator winding. Similarly, the following calculation formula can be used:

[0036]

[0037] in, L re For leakage inductance at the rotor end, N 2 and K w2 The number of turns in series per phase of the rotor and the rotor winding coefficient, p For extreme logarithms, A 2 represents the straight length of the rotor winding extending from its end. M 2 represents the axial projection length of the rotor end winding.

[0038] S3. Establish a first simulation model of the motor in the finite element software, run the first simulation model under rated operating conditions using the static magnetic field simulation technology of the finite element software, and save the stator permeability and rotor permeability, as well as the radial magnetic flux density entering the teeth of the stator and rotor in the first simulation model.

[0039] Specifically, a first simulation model of a large-capacity AC excitation motor is established in the finite element software. The static magnetic field simulation technology in the finite element software is used to obtain the simulation operation results of the large-capacity AC excitation motor under rated operating conditions (i.e., the simulation operation results of the first simulation model). The stator and rotor permeability information in the first simulation model is saved by combining the frozen permeability function.

[0040] That is, a static field finite element model of a large-capacity AC excitation motor (i.e., the first simulation model) is established, the stator and rotor current excitation is set to the stator and rotor rated current, a static field finite element simulation is run, and the permeability information of the entire motor region is saved using the frozen permeability function built into the finite element software. This permeability information is the permeability information of the motor under rated operating conditions; and the radial magnetic flux density entering the stator teeth and rotor teeth is saved.

[0041] S4, calculate the excitation inductance and harmonic leakage inductance of the stator and rotor based on the radial magnetic flux density of the teeth of the stator and rotor.

[0042] Specifically, the stator harmonic leakage inductance, rotor harmonic leakage inductance, and excitation inductance are calculated using the radial magnetic flux density entering the stator teeth and rotor teeth under rated operating conditions in step (3).

[0043] The radial magnetic flux density entering the stator teeth from the air gap includes the fundamental magnetic flux density, harmonic magnetic flux density, and a very small portion of the tooth tip leakage magnetic flux density, which can be ignored. FFT analysis is performed on the stator radial magnetic flux density to separate the corresponding harmonic magnetic flux density. B h With fundamental magnetic flux density B δ The total harmonic flux linkage (h=6k±1) and fundamental flux linkage (h=1) of the stator are calculated using the following formulas, and then the harmonic leakage inductance and magnetizing inductance of the stator are calculated:

[0044] ,

[0045] in, h For stator harmonics, l ef , τ , N 1 and K h These are the motor axial length, pole pitch, number of series turns per phase of the stator, and stator. hSecond harmonic winding coefficient B h and Ψ h The amplitude and flux linkage of the h-th harmonic magnetic flux density are given. I s This refers to the stator current amplitude. h When it is 1, B h = B δ The calculated inductance L h Magnetizing inductor L m ; h When the value is not 1, the result is... L h The harmonic leakage inductance of the stator is L shl , h =6 k ±1, k For 1, 2, 3… Z 1 / (2p), Z 1 represents the number of stator slots, and p represents the number of motor pole pairs. k Different values ​​are calculated. h The magnetic flux density of the second harmonic.

[0046] Similarly, the rotor harmonic leakage inductance is calculated by performing an FFT analysis on the radial magnetic flux density of the rotor teeth to obtain the rotor harmonic magnetic flux density. B rh Then, the harmonic leakage inductance of the rotor is calculated:

[0047] ,

[0048] in, h` For rotor harmonic order, l ef , τ , N 2 and K rh These are the motor axial length, pole pitch, number of turns per phase in series on the rotor, and rotor length, respectively. h` Second harmonic winding coefficient B rh and Ψ rhl for h` The amplitude and flux linkage of the subharmonic magnetic flux density I r This refers to the rotor current amplitude. h` =6 k ±1, k `For 1, 2, 3... Z2 / (2p), where Z2 is the number of rotor slots and p is the number of motor pole pairs. k Different rotors are calculated when different values ​​are taken. h` The magnetic flux density of the second harmonic.

[0049] S5, establish a second simulation model of the motor in the finite element software, set its stator permeability to the stator permeability in S3, and set its stator three-phase currents A, B, and C as follows: I A , I B , I C The rotor permeability was set to infinitesimal and the rotor current to 0. The second simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the stator slots and the magnetic energy stored in the air gap. W ssl and W sgl According to the formula , Calculate stator slot leakage inductance and stator tooth tip leakage inductance L ssl and L sgl ;

[0050] A third simulation model of the motor was established in the finite element software, and its rotor permeability was set to the rotor permeability in S3. The rotor three-phase currents UVW were set as follows: I U , I V , I W The stator permeability was set to infinitesimal and the stator current to 0. The third simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the rotor slots and the magnetic energy stored in the air gap. W rsl and W rgl According to the formula , Calculate rotor slot leakage inductance and rotor tooth tip leakage inductance L rsl and L rgl .

[0051] Specifically, a static field motor model with the same structure as in S3 is established in the finite element software, called the second simulation model. The mesh of this model is set to be consistent with the static field model in S3 (i.e., the first simulation model). The stator three-phase current is arbitrarily set (it must satisfy the three-phase symmetry relationship), and the rotor current is set to 0. The permeability of the rotor region is set to infinitely small, for example, 10.-7 This prevents the magnetic field generated by the stator from entering the rotor region. Combining the frozen permeability information from S3, the energy method is used to calculate the stator slot leakage inductance and stator tooth tip leakage inductance. At this point, the distribution of the stator slot leakage magnetic field lines and the stator tooth tip magnetic field lines is as follows: Figure 3 As shown:

[0052] The stator three-phase current excitation satisfies a three-phase symmetry relationship. In a static field, the stator three-phase current excitation only requires a current at a certain instant. For ease of calculation, the stator A-phase current can be used as the current. I A Set to the maximum value, the relationship between the currents of phase B, phase C, and phase A is as follows: , According to the energy method, the relationship between the amplitudes of the stator A, B, and C three-phase currents and the stator slot leakage magnetic energy storage and stator slot leakage inductance is as follows:

[0053]

[0054] Among them, L ssl W ssl and I A These are stator slot leakage inductance, stator slot leakage magnetic energy storage, and A-phase stator current amplitude, respectively.

[0055] Most of the leakage magnetic flux lines originate from one stator tooth, pass through the air gap, and return to the other stator tooth. A significant portion of the leakage magnetic energy is stored in the air gap. Therefore, the stator tooth leakage inductance can be calculated using the same method as for calculating stator slot leakage inductance. In this case, the area for energy calculation is the air gap. Similarly, according to the energy method, the relationship between the stator A, B, and C phase current amplitudes and the stator tooth leakage magnetic energy and stator tooth leakage inductance is as follows:

[0056]

[0057] in, and These are stator tooth tip leakage inductance and stator tooth tip leakage magnetic energy storage, respectively.

[0058] For example, in the finite element software, a static field motor model with the same structure as in S3 is created, i.e., the second simulation model. The mesh of this model is set to be consistent with the static field model in S3. The stator three-phase current amplitudes A, B, and C are set to 1A, -0.5A, and -0.5A respectively, and the rotor three-phase current amplitudes U, V, and W are set to 0A. The stator permeability is set to be consistent with the stator permeability saved in S3, and the permeability of the rotor region is set to 10. -7 Run a static field simulation and calculate the energy in the stator slots and the energy in the air gap using simulation software. Then, calculate the stator slot leakage inductance and the stator tooth tip leakage inductance using the following formula.

[0059] ,

[0060] in, W ssl and W sgl These represent the magnetic energy storage in the stator slots and the magnetic energy storage in the air gap, respectively. L ssl and L sgl These represent the stator slot leakage inductance and the stator tooth tip leakage inductance, respectively.

[0061] The formulas for calculating rotor slot leakage inductance and rotor tooth tip leakage inductance are as follows:

[0062] The calculation methods for rotor slot leakage inductance and rotor tooth tip leakage inductance are similar to those for stator. The setting of stator and rotor excitation currents is also similar to the calculation of stator slot leakage inductance and stator tooth tip leakage inductance. The rotor slot leakage inductance and rotor tooth tip leakage inductance can be calculated using the following formula:

[0063] ,

[0064] in, W rsl and W rgl These represent the magnetic energy storage in the rotor slots and the magnetic energy storage in the air gap, respectively. L rsl and L rgl These represent the rotor slot leakage inductance and the rotor tooth tip leakage inductance, respectively. I U This indicates the amplitude of the rotor U-phase current.

[0065] A static field motor model identical to that in S3 is established in the finite element software, referred to as the third simulation model. The mesh of this model is set to be consistent with that of the static field model in S3. The rotor three-phase current is arbitrarily set (it must satisfy the three-phase symmetry relationship), and the stator current is set to 0, and the stator region permeability is set to 10. -7 The rotor slot leakage inductance and rotor tooth tip leakage inductance were calculated using the energy method, based on the frozen permeability information in S3.

[0066] For example, establish a static field model of the motor identical to that in step S3, and set the mesh of this model to be consistent with the static field model in step S3. Set the amplitudes of the rotor three-phase currents U, V, and W to 1A, -0.5A, and -0.5A respectively, set the amplitudes of the stator three-phase currents A, B, and C to 0A, set the rotor permeability to be consistent with the permeability saved in step S3, and set the permeability of the stator region to 10. -7Run a static field simulation to calculate the energy in the rotor slots and the energy in the air gap. Then, calculate the rotor slot leakage inductance and rotor tooth tip leakage inductance using the following formula.

[0067] ,

[0068] in, W rsl and W rgl These represent the magnetic energy storage in the rotor slots and the magnetic energy storage in the air gap, respectively. L rsl and L rgl These represent the leakage inductance in the rotor slots and the leakage inductance at the rotor tooth tips, respectively.

[0069] This invention provides an electronic device, including: a computer-readable storage medium and a processor;

[0070] The computer-readable storage medium is used to store executable instructions;

[0071] The processor is configured to read executable instructions stored in the computer-readable storage medium and execute the method as described in any of the above embodiments.

[0072] This invention provides a computer-readable storage medium storing computer instructions that cause a processor to perform the method described in any of the above embodiments.

[0073] This invention provides a computer program product, including a computer program or instructions, which, when executed by a processor, implement the method described in any of the above embodiments.

[0074] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for rapid calculation of equivalent circuit parameters of a high-capacity AC excitation motor, characterized in that, include: S1, the stator leakage inductance and rotor leakage inductance of the motor are divided into slot leakage inductance, harmonic leakage inductance, tooth tip leakage inductance and end leakage inductance; wherein, the equivalent circuit parameters of the motor include magnetizing inductance, stator leakage inductance and rotor leakage inductance; S2, Select the corresponding end leakage inductance calculation formula according to the end winding shape of the motor to calculate the end leakage inductance of the stator and rotor; S3, establish a first simulation model of the motor in the finite element software, run the first simulation model under rated operating conditions using the static magnetic field simulation technology of the finite element software, and save the stator permeability and rotor permeability in the first simulation model, as well as the radial magnetic flux density entering the teeth of the stator and rotor. S4, calculate the excitation inductance and harmonic leakage inductance of the stator and rotor based on the radial magnetic flux density of the teeth of the stator and rotor; S5. Establish a second simulation model of the motor in the finite element software, set its stator permeability to the stator permeability in S3, and set its stator three-phase current. I A , I B , I C The rotor permeability was set to infinitesimal and the rotor current to 0. The second simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the stator slots and the magnetic energy stored in the air gap. W ssl and W sgl According to the formula , Calculate stator slot leakage inductance and stator tooth tip leakage inductance L ssl and L sgl ; A third simulation model of the motor is established in the finite element software, and its rotor permeability is set to the rotor permeability in S3. The rotor three-phase current is also set. I U , I V , I W The stator permeability was set to infinitesimal and the stator current to 0. The third simulation model was run using the static magnetic field simulation technology of the finite element software to save the magnetic energy stored in the rotor slots and the magnetic energy stored in the air gap. W rsl and W rgl According to the formula , Calculate rotor slot leakage inductance and rotor tooth tip leakage inductance L rsl and L rgl .

2. The method as described in claim 1, characterized in that, In step S4, the calculation methods for the excitation inductance and the stator harmonic leakage inductance are as follows: The radial magnetic flux density entering the stator teeth is processed by FFT to obtain the corresponding harmonic magnetic flux density. B h With fundamental magnetic flux density B δ According to the formula Calculate the excitation inductance and the stator harmonic leakage inductance; in, , h For stator harmonics, l ef , τ , N 1 and K h These are the motor axial length, pole pitch, number of series turns per phase of the stator, and stator. h Second harmonic winding coefficient B h and Ψ h They are respectively h Amplitude and flux linkage of secondary stator harmonic magnetic flux density I s It is the stator current amplitude; h When =1, B h = B δ , The magnetizing inductor is the inductor in the equivalent circuit. L m ; h When ≠1, B h ≠ B δ , The stator's harmonic leakage inductance, i.e., in the equivalent circuit L shl , h =6 k ±1, k For 1, 2, 3… Z 1 / (2p), Z1 is the number of stator slots, and p is the number of motor pole pairs.

3. The method as described in claim 1 or 2, characterized in that, In step S4, the harmonic leakage inductance of the rotor is calculated as follows: The radial magnetic flux density entering the rotor teeth is processed by FFT to obtain the corresponding harmonic magnetic flux density. B rh According to the formula Calculate the harmonic leakage inductance of the rotor; in, , h` For rotor harmonic order, l ef , τ , N 2 and K rh These are the motor axial length, pole pitch, number of turns per phase in series on the rotor, and rotor length, respectively. h` Second harmonic winding coefficient B rh , Ψ rhl and I r They are respectively h` The amplitude of the subharmonic magnetic flux density, the flux linkage, and the rotor current amplitude; h `=6 k ±1, k `For 1, 2, 3... Z 2 / (2p), Z 2 represents the number of stator slots, and p represents the number of motor pole pairs.

4. The method as described in claim 1, characterized in that, In step S4, the rotor permeability in the second simulation model is set to 10. -7 The stator permeability in the third simulation model is set to 10. -7 .

5. An electronic device, characterized in that, include: Computer-readable storage media and processors; The computer-readable storage medium is used to store executable instructions; The processor is configured to read executable instructions stored in the computer-readable storage medium and execute the method as described in any one of claims 1-4.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a processor to perform the method as described in any one of claims 1-4.

7. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by a processor, they implement the method as described in any one of claims 1-4.

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