Unequal-turn winding three-phase motor stator structure assembled with magnetic slot wedges, design method and motor applied by unequal-turn winding three-phase motor stator structure

Abstract

The invention discloses an unequal-turn winding three-phase motor stator structure assembled with magnetic slot wedges, a design method and a motor applying the unequal-turn winding three-phase motor stator structure assembled with the magnetic slot wedges, the stator structure comprises a stator body, stator slots are formed in the stator body, coils are arranged in the stator slots, the stator slots comprise first stator slots and second stator slots, and the coils are arranged in the first stator slots and the second stator slots. A magnetic slot wedge is arranged in the first stator slot, the difference between the actual number of turns of the A-phase belt coil and the ideal number of turns in the first stator slot is a negative number, and the magnetic slot wedge is arranged by combining the negative number with the difference between the actual number of turns of the winding coil and the ideal number of turns, so that the air gap flux density waveform of the motor tends to be sine, the amplitude of an air gap harmonic magnetic field is reduced, the THD is reduced, and the efficiency of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of motor design methods, and in particular to a stator structure of a three-phase motor with unequal turn windings equipped with magnetic slot wedges, a design method and a motor using the same. Background Art

[0002] The three-phase induction motor has the most extensive application field due to its advantages such as simple structure, stable operation and good starting performance. According to statistics, its consumption accounts for about 60% of the total power generation. There are many types of stator windings for three-phase induction motors, such as stacked windings, concentric windings, and sinusoidal windings, which can be divided into single-layer and double-layer, full-pitch and short-pitch methods. For three-phase induction motors with different pole slot parameters, the winding structure used may be different, but the winding composition principle is basically the same, that is, through the method such as "Principle and Calculation of Low Harmonic Winding" published by Ding Huazhang, the ideal turns ratio of the winding is calculated, so that the air gap synthetic magnetomotive force waveform generated by the winding is close to the sine shape, that is, the harmonic content is small and the THD is small. The three-phase induction motor is an AC motor that generates an electromagnetic torque to drive the rotor to rotate by the interaction of the rotating magnetic field formed by the stator winding and the magnetic field of the induced current in the rotor winding. However, the electric potential and magnetic field in the three-phase induction motor are not completely distributed in a sinusoidal manner in space. In addition to the fundamental wave, the magnetic potential of the stator and rotor windings also includes a series of harmonic magnetic potentials. The three-phase induction motor has uneven air gap permeability due to the presence of stator teeth and slots. Therefore, in order to achieve the purpose of making the air gap magnetic potential closer to a sine waveform, magnetic slot wedges can be installed to make the inner circular surface of the stator tend to be a smooth surface without teeth and slots, that is, to reduce the harmonic content.

[0003] Ordinary slot wedges are non-magnetic, such as the common bamboo wedges and slot wedges made of epoxy glass cloth laminate. As the name implies, magnetic slot wedges are slot wedges that can conduct magnetism. Adding different magnetic conductive materials to the materials used to make slot wedges can form magnetic slot wedges. Using magnetic slot wedges to repair and renovate motors is a reliable way to improve efficiency. Installing magnetic slot wedges on the slots of motors and turning the open slots of motors into semi-open slots or closed slots can effectively shorten the air gap length, reduce the air gap magnetic resistance, and increase the magnetic field strength accordingly. That is, by reasonably arranging the distribution of magnetic slot wedges, the air gap magnetic flux can be evenly distributed, the air gap magnetic density waveform is closer to a sine wave, and the basic iron loss and additional loss are reduced. Many scholars have conducted research on magnetic slot wedges, such as the paper "Magnetic Slot Wedges and Their Applications" published by Deng Qinghua and the paper "Energy Saving by Replacing Magnetic Slot Wedges in Motors" published by Zhao Jiali. The above research results do not consider the influence of the relative position of the magnetic slot wedge on the magnetic field waveform. It is assumed that the motor magnetomotive force only includes the air gap magnetomotive force, and the sinusoidal air gap magnetic field waveform can be obtained from the sinusoidal air gap magnetic potential waveform. Therefore, the existing stator structure design of magnetic slot wedges has the following problems:

[0004] Due to the slot fill rate requirements under different processes, the maximum number of turns of the coil in the slot may be different, and the optimal turns ratio of each coil cannot be obtained, that is, the magnetic potential waveform distortion caused by the difference between the actual number of turns and the ideal number of turns is not considered. Using the existing magnetic slot wedge matching method, it may not be possible to obtain the optimal magnetic potential waveform, even if the THD is the smallest. Summary of the invention

[0005] In order to solve the technical problems existing in the background technology, the present invention proposes a stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges, a design method and a motor with application thereof.

[0006] The present invention proposes a three-phase motor stator structure with unequal turn windings equipped with magnetic slot wedges, comprising a stator body, wherein the stator body is provided with stator slots, wherein coils are arranged in the stator slots, wherein the stator slots comprise a first stator slot and a second stator slot, wherein a magnetic slot wedge is arranged in the first stator slot, and wherein the difference between the actual number of coil turns of the A-phase belt in the first stator slot and the ideal number of turns is a negative number.

[0007] Preferably, a non-magnetic slot wedge is provided in the second stator slot.

[0008] A motor comprises the above-mentioned stator structure.

[0009] A method for designing a stator structure of a three-phase motor with unequal turn windings equipped with magnetic slot wedges comprises the following steps:

[0010] Step 1: According to the number of stator slots Z, the number of pole pairs p and the number of phases m of the stator winding, the number of slots per pole per phase of the motor is determined, q=Z / 2pm, the pole pitch τ=Z / 2p of the motor is determined, the slot number assigned to each phase belt is determined according to the spatial relationship of the symmetrical winding, and the phase belt at the lower layer position of each slot is determined according to the pitch of the concentric winding, and the slot number allocation table of each phase belt of the motor is determined;

[0011] Step 2: Using the principle of the sinusoidal distribution of slot current on the core surface, determine the ideal turns ratio of q coils in phase A as n1:n2…n q ;

[0012] Step 3: According to the requirement of maximum slot fill rate, determine the actual total number of turns in the slot with the largest number of turns, and then obtain the ideal number of turns n1, n2, ... n of phase A with q coils from the ideal turns ratio q And the actual number of turns is N1, N2, ... N q ;

[0013] Step 4: Calculate the difference between the actual number of turns of q coils in phase A and the ideal number of turns as ΔN1, ΔN2, ... ΔN q , install the magnetic slot wedge in the slot where the difference between the actual number of turns and the ideal number of turns of phase A is negative.

[0014] Specifically, in step 2: when the number of slots per pole per phase is 4, phase A is the positive phase belt, and the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C , then the numerical relationship of the slot currents in slots 1 to 4 is:

[0015]

[0016] Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal distributed slot current.

[0017] Specifically, in step 2: when the number of slots per pole per phase is 5, phase A is the positive phase belt, and the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C , then the numerical relationship of the slot currents in slots 1 to 5 is:

[0018]

[0019] Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal distributed slot current.

[0020] Specifically, in step 3, if it is determined that the coil in the q0th slot has the largest number of turns, and the slot number allocation table corresponding to the slot is A1, B2, and the actual total number of turns in the slot with the largest number of turns is determined to be M, then n1 = (M / (n1+n2))*n1, and then according to the ideal turns ratio of n1:n2…n q Calculate the ideal number of coil turns of phase A in other slots.

[0021] Specifically, the actual number of turns of the A-phase q coil in step 3 is calculated by rounding off the ideal number of turns of the A-phase q coil.

[0022] In the present invention, the proposed stator structure and design method of a three-phase motor with unequal turn windings equipped with magnetic slot wedges and the motor using the same are used to set the magnetic slot wedges based on the difference between the actual turns ratio and the ideal turns ratio of the winding coil, so that the motor air gap magnetic flux waveform tends to be sinusoidal, the amplitude of the air gap harmonic magnetic field is reduced, the THD is reduced, and the motor efficiency is improved.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the magnetic slot wedge distribution layout of implementation example 1 of the present invention;

[0025] Figure 2 It is a schematic diagram of part of the magnetic lines of force of Example 1 of the present invention;

[0026] Figure 3 is a schematic diagram of the magnetic slot wedge distribution layout of implementation example 2 of the present invention;

[0027] Figure 4 It is a schematic diagram of part of the magnetic lines of force of Example 2 of the present invention;

[0028] Figure 5 is a slot number allocation table of each phase belt of the motor in embodiment 1 of the present invention;

[0029] Figure 6 It is the finite element simulation result of the three motor models compared in Example 1 of the present invention;

[0030] Figure 7 is a slot number allocation table of each phase belt of the motor in embodiment 2 of the present invention;

[0031] Figure 8 It is the finite element simulation result of the three motor models compared in Example 2 of the present invention;

[0032] In the figure: 1. stator body; 2. stator slot; 3. magnetic slot wedge. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar symbols throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0034] like Figure 1 , Figure 3 The stator structure of a three-phase motor with unequal turns winding equipped with magnetic slot wedges shown in the figure comprises a stator body 1, a stator slot 2 is opened on the stator body 1, a coil is arranged in the stator slot, the stator slot 2 comprises a first stator slot and a second stator slot, a magnetic slot wedge 3 is arranged in the first stator slot, and the difference between the actual number of coil turns of the A-phase belt in the first stator slot and the ideal number of turns is a negative number. Preferably, a non-magnetic slot wedge is arranged in the second stator slot where the magnetic slot wedge 3 is not installed.

[0035] A motor comprises the above-mentioned three-phase motor stator structure with unequal turns windings equipped with magnetic slot wedges.

[0036] Implementation case 1: Take a 1.5kW three-phase asynchronous motor as an example. The number of stator slots of the motor is Z = 24, the number of pole pairs is p = 1, the number of phases of the stator winding is m = 3, the winding uses a 0.585mm copper wire, and the maximum slot fill rate is required to be 75%; a method for designing the stator structure of a three-phase motor with unequal turn windings equipped with magnetic slot wedges includes the following steps:

[0037] Step 1: According to the number of stator slots Z, the number of pole pairs p and the number of stator winding phases m, determine the number of slots per pole per phase of the motor q = Z / 2pm, determine the pole pitch τ = Z / 2p of the motor, determine the slot number assigned to each phase belt according to the spatial relationship of the symmetrical winding, and then determine the phase belt at the lower layer of each slot according to the pitch of the concentric winding, and finally get the following Figure 5 The slot number allocation table of each phase belt of the motor is shown.

[0038] Step 2: Using the principle of sinusoidal distribution of slot current on the core surface, determine the ideal turns ratio of q coils in a phase band as n1:n2…n q ;

[0039] If the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C Taking the positive phase belt of phase A of winding as an example, the numerical relationship of the slot current in slots 1 to 4 is:

[0040]

[0041] Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal slot current;

[0042] Assuming that the current of phase A is at its maximum value, the current amplitude relationship i can be obtained: A =-2i B =-2i C =I m The current relationship in the four slots of the positive phase belt of phase A can be simplified as:

[0043]

[0044] The ideal turns ratio of each coil in phase A is calculated to be 1.67:2.73:1.93:1 after reduction: n1:n2:n3:n4.

[0046] correspond Figure 5 , then the number of turns of the coil in A1 is n1; the ideal number of turns of the coil in A2 is n2; the ideal number of turns of the coil in A3 is n3; the ideal number of turns of the coil in A4 is n4;

[0047] The corresponding number of turns of the coil in B1 is n1; the ideal number of turns of the coil in B2 is n2; the ideal number of turns of the coil in B3 is n3; the ideal number of turns of the coil in B4 is n4;

[0048] The corresponding number of turns of the coil in C1 is n1; the ideal number of turns of the coil in C2 is n2; the ideal number of turns of the coil in C3 is n3; the ideal number of turns of the coil in C4 is n4;

[0049] Step 3: According to the requirement of the maximum slot filling rate under the actual process, in this embodiment, 75% is the maximum slot filling rate, the actual total number of turns in the slot with the largest number of turns is determined, and then the actual number of turns of q coils is obtained from the ideal turns ratio as N1, N2, ...N q ;

[0050] In this embodiment, the actual total number of turns in the third slot is the largest. According to the stator slot type and coil wire diameter and other conditions, the actual total number of turns in the slot with the largest number of turns is determined to be 54. At this time, the maximum slot fill rate is 75%, which meets the manufacturing process requirements. Using the ideal turns ratio:

[0051] n1:n2:n3:n4 is reduced to 1.67:2.73:1.93:1; then the number of turns of the coil of the A-phase belt in the third slot is (48 / (1.93+1.93))*1.93=27. According to the number of turns of the coil of the A-phase belt in the third slot, the ideal number of turns of the coils in the four slots of the A-phase belt is calculated as follows: 23.36, 38.19, 27, 13.98;

[0052] After rounding the ideal number of turns of the coil in the A-phase belt to an integer, the actual number of turns of the coil in the four slots of the A-phase belt is 23, 38, 27, and 14;

[0053] Step 4: Calculate the difference between the actual number of turns of the q coils in phase A and the ideal number of turns as ΔN1, ΔN2, ... ΔN q , install the magnetic slot wedge in the slot where the difference between the actual number of turns and the ideal number of turns is negative.

[0054] Therefore, the differences between the actual number of turns of the four coils and the ideal number of turns are ΔN1 = 0, ΔN2 = -0.33, ΔN3 = -0.26, and ΔN4 = -0.57. Install the magnetic slot wedge in the slot where the difference in turns is negative, such as Figure 1 As shown, according to the spatial relationship of the symmetrical winding, slots 2, 3, 4, 22, 23, and 24 under one pole are equipped with magnetic slot wedges, such as Figure 1 shown.

[0055] In order to verify the beneficial effects of the present invention in the first implementation case, three motor models were established, the first one was a common slot wedge solution, the second one was a magnetic slot wedge solution, and the third one was the present invention solution. Except for the slot wedge solution, the other parameters of the motors were exactly the same. The electromagnetic performance of the three motors at constant torque was calculated using the two-dimensional finite element method. Among them, the magnetic field lines of the third motor model according to the present invention are shown as follows: Figure 2 As shown in the figure, the magnetic lines of force pass through the magnetic slot wedges, while no magnetic lines of force pass through the slots without magnetic slot wedges, which shows that the existence of magnetic slot wedges increases the main magnetic flux, thereby reducing the iron loss caused by the cogging effect when the motor is running. Figure 6 As shown. The preferred slot wedge solution of the present invention has an iron loss of 64.73W, and the ordinary slot wedge solution has an iron loss of 66.79W. The iron loss of the present invention solution is 0.25% higher than that of the ordinary slot wedge solution. The THD of the present invention solution is 1.98E-04 smaller than that of the magnetic slot wedge solution, indicating that the harmonic magnetic potential waveform of the present invention solution is closer to a sine wave than that of the magnetic slot wedge solution, that is, the harmonic content is less.

[0056] Implementation Case 2: Take a 5.5kW three-phase asynchronous motor as an example. The number of stator slots of the motor is Z = 30, the number of pole pairs is p = 1, the number of phases of the stator winding is m = 3, the winding uses a 0.867mm copper wire, and the maximum slot fill rate is required to be 75%; a method for designing the stator structure of a three-phase motor with unequal turn windings equipped with magnetic slot wedges, including the following steps:

[0057] Step 1: According to the number of stator slots Z, the number of pole pairs p and the number of stator winding phases m, determine the number of slots per pole per phase of the motor q = Z / 2pm, determine the pole pitch τ = Z / 2p of the motor, determine the slot number assigned to each phase belt according to the spatial relationship of the symmetrical winding, and then determine the phase belt at the lower layer of each slot according to the pitch of the concentric winding, and finally obtain the slot number allocation table of each phase belt of the motor. The slot number allocation table of each phase belt is as follows: Figure 7 shown.

[0058] Step 2: Using the principle of sinusoidal distribution of slot current on the core surface, determine the ideal turns ratio of q coils in a phase band as n1:n2…n q ,;

[0059] If the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C Taking the positive phase belt of phase A of winding as an example, the numerical relationship of slot current in slots 1 to 5 is:

[0060]

[0061]

[0062] Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal slot current;

[0063] Assuming that the current of phase A is at its maximum value, the current amplitude relationship i can be obtained: A =-2i B =-2i C =I m The current relationship in the four slots of the positive phase belt of phase A can be simplified as:

[0064]

[0065] The ideal turns ratio of each coil in phase A can be calculated: n1:n2:n3:n4:n5 is reduced to: 0.9945:0.9945:0.7727:0.5773:0.3567

[0067] Step 3: According to the requirement that the maximum slot full rate is 75%, determine the actual total number of turns in the slot with the largest number of turns, and then obtain the actual number of turns of q coils as N1, N2, ...N from the ideal turns ratio. q :

[0068] According to the stator slot type and coil wire diameter and other conditions, the actual total number of turns in the slot with the most turns is determined to be 26. At this time, the maximum slot fill rate is 75%, which meets the manufacturing process requirements. Using the ideal turns ratio:

[0069] n1:n2:n3:n4:n5 is reduced to 0.9945:0.9945:0.7727:0.5773:0.3567;

[0070] The ideal turns of the coil of phase A in the five slots are 22.88, 22.88, 17.78, 13.28, and 8.21 respectively. The actual turns of the coil of phase A in the five slots are 23, 23, 18, 13, and 8 respectively after rounding off the ideal turns.

[0071] Step 4: Calculate the difference between the actual number of turns of q coils and the ideal number of turns as ΔN1, ΔN2, ... ΔN q , install the magnetic slot wedge in the slot where the difference between the actual number of turns and the ideal number of turns is negative.

[0072] Therefore, the differences between the actual number of turns of the five coils and the ideal number of turns are ΔN1 = 0.12, ΔN2 = 0.12, ΔN3 = 0.22, ΔN4 = -0.28, and ΔN5 = -0.21. Install the magnetic slot wedge in the slot where the difference in turns is negative, such as Figure 3As shown, due to the spatial relationship of the symmetrical winding, slots 4, 5, 28, and 29 under one pole are equipped with magnetic slot wedges, such as Figure 4 shown.

[0073] In order to verify the beneficial effects of the present invention in the first implementation case, three motor models were established, the first one was a common slot wedge solution, the second one was a magnetic slot wedge solution, and the third one was the present invention solution. Except for the slot wedge solution, the other parameters of the motors were exactly the same. The electromagnetic performance of the three motors at constant torque was calculated using the two-dimensional finite element method. Among them, the magnetic field lines of the third motor model according to the present invention are shown as follows: Figure 4 As shown, the magnetic lines of force pass through the magnetic slot wedge, and no magnetic lines of force pass through the slot without the magnetic slot wedge, which shows that the existence of the magnetic slot wedge increases the main magnetic flux, thereby reducing the iron loss caused by the cogging effect when the motor is running. The comparison of the finite element simulation results of the three motor models is shown in Table 4. The iron loss of the scheme of the present invention is 128.47W, and the iron loss of the ordinary slot wedge scheme is 131.89W. The iron loss of the scheme of the present invention is 0.17% higher than that of the ordinary slot wedge scheme. The THD of the scheme of the present invention is 1.8E-05 less than that of the magnetic slot wedge scheme, indicating that the harmonic magnetic potential waveform of this scheme is closer to the sine wave than the magnetic potential waveform of the magnetic slot wedge scheme, that is, the harmonic content is less.

[0074] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A three-phase motor stator structure with unequal turns winding equipped with magnetic slot wedges, characterized in that: The invention comprises a stator body (1), wherein a stator slot (2) is formed on the stator body (1), a coil is arranged in the stator slot (2), the stator slot (2) comprises a first stator slot and a second stator slot, a magnetic slot wedge is arranged in the first stator slot, and the difference between the actual number of coil turns of the A-phase belt in the first stator slot and the ideal number of turns is a negative number.

2. The stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges according to claim 1 is characterized in that: A non-magnetic slot wedge is arranged in the second stator slot.

3. A motor, characterized in that: Comprising a stator structure according to any one of claims 1-2.

4. A method for designing a stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges, characterized in that: The steps include: Step 1: According to the number of stator slots Z, the number of pole pairs p and the number of phases m of the stator winding, the number of slots per pole per phase of the motor is determined, q=Z / 2pm, the pole pitch τ=Z / 2p of the motor is determined, the slot number assigned to each phase belt is determined according to the spatial relationship of the symmetrical winding, and the phase belt at the lower layer position of each slot is determined according to the pitch of the concentric winding, and the slot number allocation table of each phase belt of the motor is determined; Step 2: Using the principle of the sinusoidal distribution of slot current on the core surface, determine the ideal turns ratio of q coils in phase A as n1:n2…n q ; Step 3: According to the requirement of maximum slot fill rate, determine the actual total number of turns in the slot with the largest number of turns, and then obtain the ideal number of turns n1, n2, ... n of phase A with q coils from the ideal turns ratio q And the actual number of turns is N1, N2, ... N q ; Step 4: Calculate the difference between the actual number of turns of q coils in phase A and the ideal number of turns as ΔN1, ΔN2, ... ΔN q , install the magnetic slot wedge in the slot where the difference between the actual number of turns and the ideal number of turns of phase A is negative.

5. The design method of the stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges according to claim 4 is characterized in that: In step 2: when the number of slots per pole and per phase is 4, phase A is the positive phase belt, and the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C , then the numerical relationship of the slot currents in slots 1 to 4 is: Slot 1 n1i A +n1i A =I m sin90° Slot 2 n2i A -N4i c =I m sin 75° 3rd tank n3i A -n3i c =I m sin 60° Slot 4 n4i A -n2i c =I m sin45°; Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal distributed slot current.

6. The design method of the stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges according to claim 4 is characterized in that: Specifically in step 2: when the number of slots per pole per phase is 5, phase A is the positive phase belt, and the effective value of the sinusoidal distribution slot current is I m , the instantaneous current values ​​of phase A, phase B and phase C are i A 、i B and i C , then the numerical relationship of the slot currents in slots 1 to 5 is: Slot 1 n1i A =I m sin 84° Slot 2 b2i A =I m sin 84° 3rd class A -b5i c =I m 72° Slot 4 n4i A -n4i c =I m sin 60° Slot 5 n5i A -n3i c =I m sin 48° Where: n1 is the number of coil turns of the A-phase belt in the first slot, n2 is the number of coil turns of the A-phase belt in the second slot; n3 is the number of coil turns of the A-phase belt in the third slot, and n4 is the number of coil turns of the A-phase belt in the fourth slot; m is the effective value of the sinusoidal distributed slot current.

7. The method for designing a stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges according to claim 4, characterized in that: In step 3, if it is determined that the coil in slot q0 has the most turns, and the slot number allocation table corresponding to the slot is A1, B2, and the actual total number of turns in the slot with the most turns is determined to be M, then n1 = (M / (n1+n2))*n1, and then according to the ideal turns ratio of n1:n2…n q Calculate the ideal number of coil turns of phase A in other slots.

8. The design method of the stator structure of a three-phase motor with unequal turns windings equipped with magnetic slot wedges according to claim 4 is characterized in that: The actual number of turns of the A-phase q coil in step 3 is calculated by rounding off the ideal number of turns of the A-phase q coil.

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