A method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding

Abstract

The present invention discloses a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding. The method is based on an AC static method, and a plurality of DC power supplies are used to apply a DC current to the winding end to adjust the rotor position during the test. The influence of the saturation state of the magnetic circuit under the running state on the self-inductance and mutual inductance of the winding is equivalently considered. The influence of the control mode of the actual motor drive circuit on the self-inductance and mutual inductance of the winding is considered during the test. Finally, the results of multiple indirect tests are calculated and analyzed according to the electromagnetic field equivalent principle to obtain the equivalent measured self-inductance and mutual inductance of the winding under the state without mechanical load. The present invention completes the test of the self-inductance and mutual inductance of the motor winding based on the AC static method, does not need to install a mechanical fixing device, and can consider the influence of the electromagnetic field on the inductance test result in the running state of the motor, and has the characteristics of simple structure, stable performance and reliable data.

Description

Technical Field

[0001] The invention belongs to the technical field of motor testing, and relates to a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding, in particular to a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding taking the motor running state into consideration. Background Art

[0002] At present, there are many methods for testing the inductance of permanent magnet synchronous motors, such as DC bridge test, flux linkage test, static torque test, AC static test, etc. Among them, the AC static test can relatively conveniently and accurately test the inductance of the motor winding, and the test method is easy to implement. However, there are also some problems in measuring inductance using the traditional AC static method. For example, in general, when using the AC static method to measure the inductance of the permanent magnet synchronous motor winding, an external stalling device is required to fix the rotor of the motor, which invisibly increases the equipment conditions required for the test, and the actual operating status of the motor cannot be considered during the AC static test. Summary of the invention

[0003] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is to provide a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding, which can take into account the operating state of the motor. The test of the self-inductance and mutual inductance of the motor winding is completed based on the AC static method, without the need for additional mechanical fixing devices, and can take into account the influence of the electromagnetic field on the inductance test results during the operating state of the motor.

[0004] In order to solve the above technical problems, a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding is provided, comprising the following steps: selecting any phase winding as the A phase, the phase that is 120° counterclockwise different from the A phase as the B phase, the phase that is 120° clockwise different from the A phase as the C phase, and the phases that are 30° different from the A phase, the B phase and the C phase are respectively the U phase, the V phase and the W phase;

[0005] Step 1: Add a DC power input 1 between the AB phase windings of the motor. The DC power input 1 provides a constant DC current of I1. At the same time, add a DC power input 2 between the AC phase windings of the motor. The DC power input 2 provides a constant DC current of I2 to generate an electromagnetic torque to fix the rotor and simulate the electromagnetic field distribution inside the motor when the motor is running.

[0006] Step 2: Connect the lead wire of the motor U-phase winding to the single-phase output terminal of the inverter, supply AC power of a predetermined frequency to the motor U-phase, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment. The test data includes the terminal voltage of the motor UVW three-phase winding, the U-phase winding current and the U-phase winding electric power;

[0007] Step 3: Stop energizing the U-phase winding, change the magnitude of I1 and I2 or change the magnitude and direction of I1 and I2 at the same time, and then repeat steps 1 and 2. The currents I1 and I2 satisfy I1+I2=I q , I q is the quadrature axis current value of the current comprehensive vector when the motor is running. The setting number of repetitions is changed to obtain the U-phase winding self-inductance when the motor rotor is in different positions, which is recorded as the motor winding self-inductance reference value L UU1 ;

[0008] Step 4: The U phase winding is energized again, and a DC power input 1 is added between the CV phase windings of the motor. The DC power input 1 provides a constant DC current of I3. At the same time, a DC power input 2 is added between the CW phase windings of the motor. The DC power input 2 provides a constant DC current of I4 to generate an electromagnetic torque that fixes the rotor and simulates the electromagnetic field distribution inside the motor when the motor is running.

[0009] Step 5: Connect the lead wire of the U-phase winding of the motor to the single-phase output terminal of the inverter, pass the AC power of the predetermined frequency to the U-phase winding of the motor, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment. The test data includes the terminal voltage of the UAB three-phase winding of the motor, the U-phase winding current and the U-phase winding electric power;

[0010] Step 6: Stop energizing the U-phase winding, change the magnitude of I3 and I4 or change the magnitude and direction of I3 and I4 at the same time, and then repeat steps 4 and 5. The currents I3 and I4 satisfy I3+I4=I q , I q The quadrature axis current value of the current comprehensive vector when the motor is running is changed and repeated for a set number of times. The self-inductance of the U-phase winding when the motor rotor is in different positions is obtained by testing. The self-inductance of the U-phase winding is recorded as the reference value of the winding self-inductance of the motor L. UU2 ;

[0011] Step 7: According to the actual driving mode of the permanent magnet synchronous motor, the winding self-inductance reference L in step 3 and step 6 UU1 And winding self-inductance reference L UU2 The test data obtained in step 2 and step 5 are used to obtain the test results of winding self-inductance, mutual inductance between closely adjacent windings, mutual inductance between far adjacent windings, and mutual inductance between separated windings considering the motor operating state.

[0012] Furthermore, in step 3, the U-phase winding self-inductance L UU1 for:

[0013]

[0014] Where ω is the angular frequency of the sinusoidal alternating current, U U1 ,IU1 are the voltage effective value and current effective value of the U-phase winding obtained according to the test data in step 2, and P is the winding copper loss.

[0015] Furthermore, in step 6, the U-phase winding self-inductance L UU2 for:

[0016]

[0017] Where ω is the angular frequency of the sinusoidal alternating current, U U2 ,I U2 are the voltage and current effective values ​​of the U-phase winding obtained according to the test data in step 5, and P is the winding copper loss

[0018] Furthermore, in step 7, the winding self-inductance considering the motor running state is:

[0019] L S =aL UU1 +bL UU2

[0020] Among them, L S In order to consider the winding self-inductance of the motor running state, a is the proportion of the upper and lower bridge arms conducting mode in alternate phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy, and b is the proportion of the upper and lower bridge arms conducting mode in adjacent phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy.

[0021] Furthermore, in step 7, the mutual inductance between adjacent windings considering the motor running state is:

[0022]

[0023] Where ω is the angular frequency of the sinusoidal alternating current, L m1 To consider the mutual inductance between adjacent windings in the motor operation state, U A and I U2 are the effective values ​​of the A-phase winding voltage and the U-phase winding current obtained according to the test data in step five.

[0024] Furthermore, in step 7, the mutual inductance between distant adjacent windings considering the motor running state is:

[0025]

[0026] Where ω is the angular frequency of the sinusoidal alternating current, L m2 To consider the mutual inductance between distant adjacent windings in the motor operation state, U B and I U2 is the effective value of the B-phase winding voltage and the effective value of the U-phase winding current obtained according to the test data in step five.

[0027] Furthermore, in step 7, the mutual inductance between the separated windings considering the motor running state is:

[0028]

[0029] Where ω is the angular frequency of the sinusoidal alternating current, L m3 To consider the mutual inductance between the separated windings in the running state of the motor, U V and U W is the effective value of the V-phase and W-phase winding voltages obtained from the test data in step 2, I U1 is the effective value of the current of the U-phase winding obtained according to the test data in step 2.

[0030] Beneficial effects of the present invention: The present invention utilizes the multi-winding structural characteristics of the asymmetric six-phase permanent magnet synchronous motor and combines the AC static method to test the self-inductance of the motor winding and its mutual inductance with adjacent windings and the mutual inductance of alternate windings. By using this method to test the self-inductance and mutual inductance of the motor winding, the self-inductance of a phase winding and its mutual inductance with adjacent windings and the mutual inductance of alternate windings can be tested when the motor is in any position while considering the operating state of the motor. It not only eliminates the need for an external rotor blocking device, but also improves the test accuracy of the motor's self-inductance and mutual inductance, making it closer to the true value of the motor's self-inductance and mutual inductance under the motor's operating state. In the process of testing the motor inductance using the method of the present invention, the motor casing and shaft extension do not need to be specially fixed, and no external equipment is required. It has a series of advantages such as simple structure, stable performance, and reliable data, and can meet the general needs of motor inductance testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The circuit connection diagram described in step 1 of the method of the present invention;

[0032] Figure 2 The circuit connection diagram described in step 2 of the method of the present invention;

[0033] Figure 3 The circuit connection diagram described in step 4 of the method of the present invention;

[0034] Figure 4 The circuit connection diagram described in step 5 of the method of the present invention;

[0035] Figure 5 The structure diagram of the asymmetric six-phase permanent magnet synchronous motor of the present invention is shown in FIG. The three phases ABC are symmetrical, and the phases differ by 120 electrical degrees; the three phases UVW are symmetrical, and the phases differ by 120 electrical degrees; and the phase A and the phase U differ by 30 electrical degrees. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with the embodiments and the accompanying drawings.

[0037] Embodiment 1:

[0038] The present invention provides a method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding, and the steps are as follows:

[0039] Step 1: Add a DC power input 1 between the AB phase windings of the motor, and the DC power input 1 is used to provide a constant DC current of I1. At the same time, add a DC power input 2 between the AC phase windings of the motor, and the DC power input 2 is used to provide a constant DC current of I2 to generate an electromagnetic torque to fix the rotor and simulate the electromagnetic field distribution inside the motor when the motor is running.

[0040] Step 2: Connect the U-phase lead wire of the motor to the single-phase output terminal of the inverter, supply AC power of a predetermined frequency to the U-phase of the motor, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment. The test data includes the terminal voltage of the motor UVW three-phase windings, the U-phase current and the U-phase electric power.

[0041] Step 3: Stop the power supply, change the direction and magnitude of the input currents I1 and I2, and the currents I1 and I2 satisfy I1+I2=I q (I q is the cross-axis current value of the comprehensive current vector when the motor is running) and then repeat steps 1 and 2 to test the self-inductance of the U-phase winding when the motor rotor is in different positions, as well as the mutual inductance between the UV-phase windings and the mutual inductance between the UW-phase windings. The self-inductance of the U-phase winding at this time is recorded as the winding self-inductance reference value 1 of the motor, and the average value of the mutual inductance between the UV-phase windings and the mutual inductance between the UW-phase windings is recorded as the mutual inductance between the phases.

[0042] Step 4: Restart powering on, add a DC power input 1 between the CV phase windings of the motor, the DC power input 1 is used to provide a constant DC current of I3, and at the same time, add a DC power input 2 between the CW phase windings of the motor, the DC power input 2 is used to provide a constant DC current of I4 to generate an electromagnetic torque to fix the rotor, and at the same time simulate the electromagnetic field distribution inside the motor when the motor is running.

[0043] Step 5: Connect the U-phase lead wire of the motor to the single-phase output terminal of the inverter, supply AC power of a predetermined frequency to the U-phase of the motor, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment, which includes the terminal voltage of the three-phase windings UAB of the motor, the U-phase current and the U-phase electric power.

[0044] Step 6: Stop the power supply, change the direction and magnitude of the input currents I3 and I4, and the currents I3 and I4 satisfy I3+I4=I q (I qis the cross-axis current value of the comprehensive current vector when the motor is running), and then repeat steps 4 and 5 to test the self-inductance of the U-phase winding when the motor rotor is in different positions, as well as the mutual inductance between the UA-phase windings and the mutual inductance between the UB-phase windings. At this time, the self-inductance of the U-phase winding is recorded as the motor's winding self-inductance reference 2, the mutual inductance between the UA-phase windings is recorded as the mutual inductance between closely adjacent windings, and the mutual inductance between the UB-phase windings is recorded as the mutual inductance between far adjacent windings.

[0045] Step 7: According to the actual driving mode of the permanent magnet synchronous motor and the winding self-inductance reference 1 and the winding self-inductance reference 2 in steps 3 and 6, the winding self-inductance, the mutual inductance between adjacent windings, the mutual inductance between distant adjacent windings, and the mutual inductance between separated windings considering the motor operating state can be obtained.

[0046] Embodiment 2:

[0047] like Figure 1 to Figure 5 As shown, a method for testing the self-inductance of a permanent magnet synchronous motor winding and the mutual inductance between windings involved in this embodiment comprises the following steps:

[0048] Step 1: Add a DC power input 1 between the AB phase windings of the motor, and the DC power input 1 is used to provide a constant DC current of I1. At the same time, add a DC power input 2 between the AC phase windings of the motor, and the DC power input 2 is used to provide a constant DC current of I2 to generate an electromagnetic torque that fixes the rotor and simulates the electromagnetic field distribution inside the motor when the motor is running. The specific electrical connections are as follows: Figure 1 shown.

[0049] Step 2: Connect the U-phase lead wire of the motor to the single-phase output terminal of the inverter, supply the motor with AC power of a predetermined frequency, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment, which includes the terminal voltage of the motor UVW three-phase winding, the U-phase current and the U-phase electric power. The specific electrical connection is as follows: Figure 2 shown.

[0050] Step 3: Stop the power supply, change the direction and magnitude of the input currents I1 and I2, and the currents I1 and I2 satisfy I1+I2=I q (I q is the quadrature axis current value of the current comprehensive vector when the motor is running) and then repeat steps 1 and 2 to test the self-inductance of the U-phase winding when the motor rotor is in different positions, the mutual inductance between the UV-phase windings, and the mutual inductance between the UW-phase windings. The self-inductance of the U-phase winding at this time is recorded as the winding self-inductance reference value L of the motor UU1 , mutual inductance L between UV phase windings UV and the mutual inductance L between the UW phase windings UW The average value is recorded as the mutual inductance L between the windings. m3 .

[0051] Calculation of the self-inductance and mutual inductance of the permanent magnet synchronous motor winding under the test method of the present invention:

[0052] The voltage equation of the symmetrical five-phase permanent magnet synchronous motor winding can be written in the following matrix form:

[0053]

[0054] Among them, u=[u A u B u C u D u E ],i=[i A i B i C i D i E ],ψ=L·i,

[0055]

[0056] Then the voltage equation of the jth winding is

[0057]

[0058] in, L jj is the self-inductance of the jth winding, L kj The mutual inductance between the kth winding and the jth winding.

[0059] In fact, the self-inductance and mutual inductance of the winding are both the rotor position angle θ r function, so formula (2) can be written as follows:

[0060]

[0061] When using the static measurement method to determine the winding inductance parameters, the motor rotor is fixed and does not move. Then formula (3) can be simplified to

[0062]

[0063] At this time, a sinusoidal alternating current i is passed through the jth winding. j , when the kth winding is open. Then the voltage equation of the jth winding and the kth winding can be written as

[0064]

[0065]

[0066] Write the above formula in plural form

[0067] U j =r j I j +jωL jj I j

[0068] U k =jωL kj I j

[0069] Among them, U j , U k , I j are the effective values ​​of the corresponding voltage and current, and ω is the angular frequency of the sinusoidal alternating current.

[0070] When the motor rotor is fixed at a certain rotor position angle θ r When the self-inductance of the jth winding is

[0071]

[0072] In actual measurement, by measuring the winding copper loss P and current I j , the resistance of the winding can be obtained as follows

[0073]

[0074] Then the self-inductance of the jth winding can be expressed as

[0075]

[0076] The mutual inductance between the jth winding and the kth winding is

[0077]

[0078] According to the above formula, a sinusoidal alternating current i is passed through the jth winding. j , and when the kth winding is open, the current of the jth winding, the voltage of the jth winding, the power of the jth winding and the voltage of the kth winding are measured to calculate the self-inductance of the jth winding and the mutual inductance between the kth winding and the jth winding.

[0079] Step 4: Restart powering on, add DC power input 1 between the CV phase windings of the motor, the DC power input 1 is used to provide a constant DC current of I3, and at the same time, add DC power input 2 between the CW phase windings of the motor, the DC power input 2 is used to provide a constant DC current of I4, to generate an electromagnetic torque to fix the rotor, and at the same time simulate the electromagnetic field distribution inside the motor when the motor is running. The specific electrical connection is as follows Figure 3 shown.

[0080] Step 5: Connect the U-phase lead wire of the motor to the single-phase output terminal of the inverter, supply the motor with AC power of a predetermined frequency, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment, which includes the terminal voltage of the motor UAB three-phase winding, the U-phase current and the U-phase electric power. The specific electrical connection is as follows: Figure 4 shown.

[0081] Step 6: Stop the power supply, change the direction and magnitude of the input currents I3 and I4, and the currents I3 and I4 satisfy I3+I4=I q (I q is the quadrature axis current value of the current comprehensive vector when the motor is running), and then repeat steps 4 and 5 to test the self-inductance of the U-phase winding when the motor rotor is in different positions, the mutual inductance between the UA-phase windings, and the mutual inductance between the UB-phase windings. The self-inductance of the U-phase winding at this time is recorded as the winding self-inductance reference value L of the motor UU2 , the mutual inductance between the UA phase windings is recorded as the mutual inductance between adjacent windings L UA , the mutual inductance between the UB phase windings is recorded as the mutual inductance between the distant adjacent windings L UB .

[0082] Step 7: According to the actual driving mode of the permanent magnet synchronous motor and the winding self-inductance reference 1 and winding self-inductance reference 2 in step 3 and step 6, the winding self-inductance, the mutual inductance between adjacent windings, and the mutual inductance between separated windings considering the motor running state can be obtained. The specific calculation formula is as follows:

[0083] L S =aL UU1 +bL UU2

[0084] Among them, L S These are the test results of the self-inductance of the asymmetric six-phase permanent magnet synchronous motor winding considering the operating state of the motor. a is the proportion of the upper and lower bridge arms conducting in alternate phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy. b is the proportion of the upper and lower bridge arms conducting in adjacent phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy.

[0085]

[0086] Among them, L m3 The test results of the mutual inductance of the separated windings of the asymmetric six-phase permanent magnet synchronous motor considering the motor running state, U V , U W and I U1 This is the test result in step 2.

[0087]

[0088] Among them, Lm1 The test results of the mutual inductance of adjacent windings of an asymmetric six-phase permanent magnet synchronous motor considering the motor operation state, U A and I U2 This is the test result in step 5.

[0089]

[0090] Among them, L m2 The test results of the mutual inductance of the distant adjacent windings of the asymmetric six-phase permanent magnet synchronous motor considering the motor running state, U B and I U2 This is the test result in step 5.

[0091] The above descriptions are only preferred specific embodiments of the present invention, which are all different implementation methods based on the overall concept of the present invention, and the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for testing the self-inductance and mutual inductance of an asymmetric six-phase permanent magnet synchronous motor winding, characterized in that: The following steps are involved: Select any phase winding as phase A, the phase that is 120° counterclockwise from phase A as phase B, the phase that is 120° clockwise from phase A as phase C, and the phases that are 30° different from phase A, phase B, and phase C are respectively U phase, V phase, and W phase; Step 1: between the AB phase windings of the motor, a DC power input 1 is added, and the DC power input 1 provides a constant DC current of I1. At the same time, between the AC phase windings of the motor, a DC power input 2 is added, and the DC power input 2 provides a constant DC current of I2, so as to generate an electromagnetic torque to fix the rotor and simulate the electromagnetic field distribution inside the motor when the motor is running; Step 2: Connect the lead wire of the motor U-phase winding to the single-phase output terminal of the frequency converter, supply AC power of a predetermined frequency to the motor U-phase, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment, wherein the test data includes the terminal voltage of the motor UVW three-phase winding, the U-phase winding current and the U-phase winding electric power; Step 3: Stop energizing the U-phase winding, change the magnitude of I1 and I2 or change the magnitude and direction of I1 and I2 at the same time, and then repeat steps 1 and 2. The currents I1 and I2 satisfy I1+I2=I q , I q is the quadrature axis current value of the current comprehensive vector when the motor is running. The setting number of repetitions is changed to obtain the U-phase winding self-inductance when the motor rotor is in different positions, which is recorded as the motor winding self-inductance reference value L UU1 ; Step 4: The U phase winding is energized again, and a DC power input 1 is added between the CV phase windings of the motor, and the DC power input 1 provides a constant DC current of I3. At the same time, a DC power input 2 is added between the CW phase windings of the motor, and the DC power input 2 provides a constant DC current of I4 to generate an electromagnetic torque that fixes the rotor, and at the same time simulate the electromagnetic field distribution inside the motor when the motor is running; Step 5: Connect the lead wire of the U-phase winding of the motor to the single-phase output terminal of the frequency converter, pass the AC power of a predetermined frequency to the U-phase winding of the motor, adjust the voltage to the rated voltage through the voltage regulator, and record the test data at the current moment, wherein the test data includes the terminal voltage of the three-phase windings UAB of the motor, the U-phase winding current and the U-phase winding electric power; Step 6: Stop energizing the U-phase winding, change the magnitude of I3 and I4 or change the magnitude and direction of I3 and I4 at the same time, and then repeat steps 4 and 5. The currents I3 and I4 satisfy I3+I4=I q , I q The quadrature axis current value of the current comprehensive vector when the motor is running is changed and repeated for a set number of times. The self-inductance of the U-phase winding when the motor rotor is in different positions is obtained by testing. The self-inductance of the U-phase winding is recorded as the reference value of the winding self-inductance of the motor L. UU2 ; Step 7: According to the actual driving mode of the permanent magnet synchronous motor, the winding self-inductance reference L in step 3 and step 6 UU1 And winding self-inductance reference L UU2 The test data obtained in step 2 and step 5 are used to obtain the test results of winding self-inductance, mutual inductance between closely adjacent windings, mutual inductance between far adjacent windings, and mutual inductance between separated windings considering the motor operating state.

2. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: Step 3: U-phase winding self-inductance L UU1 for: Where ω is the angular frequency of the sinusoidal alternating current, U U1 ,I U1 are the voltage effective value and current effective value of the U-phase winding obtained according to the test data in step 2, and P is the winding copper loss.

3. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: Step 6: U-phase winding self-inductance L UU2 for: Where ω is the angular frequency of the sinusoidal alternating current, U U2 ,I U2 are respectively the voltage effective value and current effective value of the U-phase winding obtained according to the test data in step 5, and P is the winding copper loss.

4. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: The winding self-inductance considering the motor running state described in step 7 is: <h2 style=";text-align:left;direction:ltr">L<h2 style=";text-align:left;direction:ltr"> S <h2 style=";text-align:left;direction:ltr"> =aL<h2 style=";text-align:left;direction:ltr"> UU1 <h2 style=";text-align:left;direction:ltr"> +bL<h2 style=";text-align:left;direction:ltr"> UU2 Among them, L S In order to consider the winding self-inductance of the motor running state, a is the proportion of the upper and lower bridge arms conducting mode in alternate phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy, and b is the proportion of the upper and lower bridge arms conducting mode in adjacent phases when the asymmetric six-phase permanent magnet synchronous motor adopts the space vector control control strategy.

5. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: The mutual inductance between adjacent windings considering the motor running state described in step 7 is: Where ω is the angular frequency of the sinusoidal alternating current, L m1 To consider the mutual inductance between adjacent windings in the motor operation state, U A and I U2 are the effective values ​​of the A-phase winding voltage and the U-phase winding current obtained according to the test data in step five.

6. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: The mutual inductance between distant adjacent windings considering the motor running state described in step 7 is: Where ω is the angular frequency of the sinusoidal alternating current, L m2 To consider the mutual inductance between distant adjacent windings in the motor operation state, U B and I U2 is the effective value of the B-phase winding voltage and the effective value of the U-phase winding current obtained according to the test data in step five.

7. The method for testing the self-inductance and mutual inductance of windings of an asymmetric six-phase permanent magnet synchronous motor according to claim 1, characterized in that: The mutual inductance between the windings in step 7 considering the motor running state is: Where ω is the angular frequency of the sinusoidal alternating current, L m3 To consider the mutual inductance between the separated windings in the running state of the motor, U V and U W is the effective value of the V-phase and W-phase winding voltages obtained from the test data in step 2, I U1 is the effective value of the current of the U-phase winding obtained according to the test data in step 2.

Images