A method and system for determining pole slot of an integrated winding bearingless permanent magnet motor

Abstract

The application discloses a pole slot determination method and system of an integrated winding bearingless permanent magnet motor, and relates to the technical field of motor design. The method comprises the following steps: determining the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding based on the principle of integrated winding suspension force generation; determining the number of slots of the bearingless permanent magnet motor to be designed according to the number of pole pairs and the number of unit motors of the rotor based on the theory of alternating current winding; and obtaining the bearingless permanent magnet motor according to the number of pole pairs and the number of slots of the rotor. The application can realize the design of the integrated winding bearingless permanent magnet motor, so that a miniaturized motor structure is obtained.

Description

Technical Field

[0001] This invention relates to the field of motor design technology, and in particular to a method and system for determining pole slots in an integrated winding bearingless permanent magnet motor. Background Technology

[0002] Traditional motors use mechanical bearings to support the rotor. When the motor runs at high speed, there will be a large friction between the mechanical bearing and the rotor, which will cause adverse effects such as accelerated motor wear, increased temperature, reduced motor life and reduced motor system stability.

[0003] Bearingless motors offer advantages such as no bearing wear, no mechanical noise, and no need for lubrication. They also boast a compact structure, high power density, reduced system cost, and ease of achieving high speeds and high power. Compared to traditional motors, bearingless motors achieve stable rotation and levitation by adding an additional levitation winding (with a pole pair number ±1 different from the torque winding) within the stator slots that already contain a torque winding. Adjusting the current magnitude and phase in these two windings allows for stable operation. However, the shared stator slot space and the strict limitations on winding direction and overlap increase the complexity of stator and rotor design and manufacturing processes. The use of two windings also increases power losses on the stator side, limiting the further development of bearingless motors.

[0004] Compared to traditional bearingless motors that use two sets of windings (torque winding and suspension winding), bearingless motors with integrated winding structures reduce slots, allowing for a more compact stator structure and ultimately, miniaturization of the motor. However, the electromagnetic structure design theory for bearingless motors with integrated windings is still incomplete and lacks sufficient theoretical support. Therefore, a method for determining the pole slots of bearingless permanent magnet motors with integrated windings is urgently needed. Summary of the Invention

[0005] Based on this, embodiments of the present invention provide a method and system for determining the pole slots of an integrated winding bearingless permanent magnet motor, thereby realizing the design of an integrated winding bearingless permanent magnet motor and obtaining a miniaturized motor structure.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for determining the pole slots of an integrated winding bearingless permanent magnet motor includes:

[0008] Based on the principle of levitation force generation of integrated windings, the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding is determined.

[0009] Based on AC winding theory, the number of slots of the bearingless permanent magnet motor to be designed is determined according to the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors.

[0010] A bearingless permanent magnet motor is obtained based on the number of pole pairs and the number of slots of the rotor.

[0011] Optionally, determining the number of unit motors relative to the torque winding of the bearingless permanent magnet motor to be designed, based on the principle of levitation force generation of integrated windings, specifically includes:

[0012] If the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed is p, then the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding is determined to be 2; where p = 4N, N = 3a ± 1, a = 0, 1, 2...

[0013] Optionally, the step of determining the number of slots of the bearingless permanent magnet motor to be designed based on AC winding theory, according to the number of pole pairs of the rotor and the number of unit motors, specifically includes:

[0014] Using AC winding theory, the first calculation formula and the second calculation formula are determined by the number of pole pairs of the rotor and the number of unit motors;

[0015] The first calculation formula is:

[0016]

[0017] q represents the number of slots per pole per phase; Z represents the number of slots in the bearingless permanent magnet motor to be designed; p represents the number of pole pairs of the rotor. After simplification, it becomes N1 is the numerator after simplification; D is the denominator after simplification; when q represents the integer slot, D = 1, N1 = q; when q represents the fraction slot, D ≠ 1, and N1 and D have no common divisor.

[0018] The second calculation formula is:

[0019]

[0020] t1 is the number of unit motors;

[0021] Substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors into the second calculation formula to obtain the value of the denominator after simplification;

[0022] Substitute the simplified denominator value and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

[0023] Optionally, the number of slots of the bearingless permanent magnet motor to be designed is 12n+6; where n≥0 and n is an integer.

[0024] The present invention also provides a pole and slot determination system for an integrated winding bearingless permanent magnet motor, comprising:

[0025] The module for determining the number of unit motors is used to determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding, based on the principle of generating levitation force of integrated windings.

[0026] The slot number range determination module is used to determine the number of slots of the bearingless permanent magnet motor to be designed based on AC winding theory, according to the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors.

[0027] A bearingless permanent magnet motor design module is used to obtain a bearingless permanent magnet motor based on the number of pole pairs and the number of slots of the rotor.

[0028] Optionally, the module for determining the number of unit motors specifically includes:

[0029] The unit for determining the number of unit motors is used to determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding as 2 if the number of pole pairs of the rotor is p; where p = 4N, N = 3a ± 1, a = 0, 1, 2...

[0030] Optionally, the slot number range determination module specifically includes:

[0031] The calculation formula determination unit is used to determine the first calculation formula and the second calculation formula by using AC winding theory, based on the number of pole pairs of the rotor and the number of unit motors.

[0032] The first calculation formula is:

[0033]

[0034] q represents the number of slots per pole per phase; Z represents the number of slots in the bearingless permanent magnet motor to be designed; p represents the number of pole pairs of the rotor. After simplification, it becomes N1 is the numerator after simplification; D is the denominator after simplification; when q represents the integer slot, D = 1, N1 = q; when q represents the fraction slot, D ≠ 1, and N1 and D have no common divisor.

[0035] The second calculation formula is:

[0036]

[0037] t1 is the number of unit motors;

[0038] The unit for determining the denominator value after simplification is used to substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors into the second calculation formula to obtain the value of the denominator after simplification.

[0039] The slot number determination unit is used to substitute the value of the denominator after simplification and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

[0040] Optionally, the number of slots of the bearingless permanent magnet motor to be designed is 12n+6; where n≥0 and n is an integer.

[0041] Compared with the prior art, the beneficial effects of the present invention are:

[0042] This invention proposes a method and system for determining the poles and slots of an integrated winding bearingless permanent magnet motor. Based on the principle of levitation force generation in integrated windings, the number of unit motors relative to the torque winding of the bearingless permanent magnet motor to be designed is determined. Based on AC winding theory, the number of slots of the bearingless permanent magnet motor to be designed is determined according to the number of pole pairs and the number of unit motors of the rotor. The bearingless permanent magnet motor is then obtained based on the number of pole pairs and slots of the rotor. This invention achieves the design of an integrated winding bearingless permanent magnet motor by determining the number of pole pairs and slots, thereby obtaining a miniaturized motor structure. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 A flowchart of a method for determining the pole slots of an integrated winding bearingless permanent magnet motor provided in an embodiment of the present invention;

[0045] Figure 2 A cross-sectional view of an 8-stage, 18-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0046] Figure 3 A cross-sectional view of an 8-stage, 30-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0047] Figure 4 A cross-sectional view of an 8-stage, 42-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0048] Figure 5 A winding distribution diagram of an 8-stage, 18-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0049] Figure 6 A winding distribution diagram of an 8-stage, 30-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0050] Figure 7A winding distribution diagram of an 8-stage 42-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0051] Figure 8 A schematic diagram of the levitation force and torque waveforms of an 8-stage 18-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0052] Figure 9 A schematic diagram of the levitation force and torque waveforms of an 8-stage 30-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0053] Figure 10 A schematic diagram of the levitation force and torque waveforms of an 8-stage 42-slot bearingless permanent magnet motor provided in an embodiment of the present invention;

[0054] Figure 11 A schematic diagram of the structure of an integrated winding bearingless permanent magnet motor system based on an integrated winding bearingless permanent magnet motor design provided in an embodiment of the present invention;

[0055] Figure 12 This is a schematic diagram of the pole slot determination system for an integrated winding bearingless permanent magnet motor provided in an embodiment of the present invention. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0058] Figure 1 A flowchart illustrating the pole and slot determination method for an integrated winding bearingless permanent magnet motor provided in an embodiment of the present invention. See also... Figure 1 The pole slot determination method of the integrated winding bearingless permanent magnet motor in this embodiment includes:

[0059] Step 101: Based on the principle of levitation force generation of integrated windings, determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding.

[0060] Step 101 specifically includes:

[0061] To design a suitable pole slot for an 8N (N = 3a ± 1, a = 0, 1, 2…) pole-number integrated winding bearingless permanent magnet motor, i.e., the rotor pole pairs of the bearingless permanent magnet motor to be designed are 4N (N = 3a ± 1, a = 0, 1, 2…), based on the principle of levitation force generation in integrated windings, the number of unit motors relative to the torque winding of the bearingless permanent magnet motor is determined to be 2. The specific determination process is as follows:

[0062] Figure 2 The diagram shows a cross-sectional view of a three-phase, four-pole, 18-slot bearingless integrated winding permanent magnet motor, with a schematic diagram of the current excitation applied to the six independent winding coils as shown. Figure 2 As shown, the current in each independent winding coil is the superposition of the currents that generate levitation force and torque force. The currents of the six-phase windings A, C, B, D, F, and E are set to I1, I2, I3, I4, I5, and I6, respectively.

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069] p is the number of pole pairs of the motor rotor, ω is the mechanical angular velocity of the rotor, and I T I C These are the amplitudes of the torque current and the levitation current, respectively. These are the initial angles of the torque current and the levitation current, respectively, where t represents time, and I... Ta I Tb I Tc These represent the torque current amplitudes of phases a, b, and c, respectively. Ca I Cb I Cc These are the floating current amplitudes for phases a, b, and c, respectively.

[0070] From the expressions for levitation current and torque levitation current, it can be seen that the number of pole pairs of the magnetic field generated by the torque current within a unit motor is twice the number of pole pairs of the magnetic field generated by the levitation current. If the entire motor consists of t2 unit motors, then the magnetic field generated by the torque current is t1 = 2t2 pole pairs (relative to the torque winding, the entire motor consists of t1 unit motors), and the magnetic field generated by the levitation current is t2 pole pairs. According to the conditions for generating levitation force, to generate stable levitation force, the number of pole pairs of the torque magnetic field and the levitation magnetic field must differ by 1, so 2t2 ± t2 = 1, therefore t1 = 2t2 = 2.

[0071] Step 102: Based on AC winding theory, determine the number of slots of the bearingless permanent magnet motor to be designed according to the number of pole pairs of the rotor and the number of unit motors.

[0072] Step 102 specifically includes:

[0073] 1) Using AC winding theory, the first calculation formula and the second calculation formula are determined by the number of pole pairs of the rotor and the number of unit motors.

[0074] The first calculation formula is:

[0075]

[0076] q represents the number of slots per pole per phase; Z represents the number of slots in the bearingless permanent magnet motor to be designed; p represents the number of pole pairs of the rotor. After simplification, it becomes N1 is the numerator after simplification; D is the denominator after simplification; when q represents the integer slot, D = 1, N1 = q; when q represents the fraction slot, D ≠ 1, and N1 and D have no common divisor.

[0077] The second calculation formula is:

[0078]

[0079] t1 represents the number of motors in the unit.

[0080] 2) Substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors into the second calculation formula to obtain the value of the denominator after simplification.

[0081] 3) Substitute the value of the denominator after simplification and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

[0082] The bearingless permanent magnet motor to be designed has 12n+6 slots; where n≥0 and n is an integer.

[0083] Step 103: Obtain the bearingless permanent magnet motor based on the number of pole pairs and the number of slots of the rotor.

[0084] This embodiment specifically designs an 8-pole / 12n+6-slot bearingless permanent magnet motor, where 8 poles indicates the number of poles on the rotor of the bearingless permanent magnet motor. Cross-sectional diagrams of 8-pole / 18-slot, 8-pole / 30-slot, and 8-pole / 42-slot bearingless permanent magnet motors are shown below. Figure 2 , Figure 3 , Figure 4 As shown; the winding distribution diagrams of 8-stage 18-slot, 8-stage 30-slot, and 8-stage 42-slot bearingless permanent magnet motors are as follows. Figure 5 , Figure 6 , Figure 7 As shown; the levitation force and torque waveforms of 8-stage 18-slot, 8-stage 30-slot, and 8-stage 42-slot bearingless permanent magnet motors are as follows. Figure 8 , Figure 9 , Figure 10 As shown; Figure 5 , Figure 6 , Figure 7 In the diagram, U, V, and W represent the first set of three-phase windings, X, Y, and Z represent the second set of three-phase windings, and the numbers 1 and 2 represent current inflow and outflow, respectively.

[0085] The pole and slot determination method for the integrated winding bearingless permanent magnet motor provided in this embodiment, based on the principle of levitation force generation and the theory of fractional-slot AC windings, derives a pole and slot configuration for a bearingless permanent magnet motor that integrates torque windings and levitation windings to generate stable torque and stable levitation force. This pole and slot configuration motor structure is applicable to both concentrated and distributed windings.

[0086] The integrated winding bearingless permanent magnet motor system proposed in this embodiment is as follows: Figure 11 As shown, the integrated winding bearingless permanent magnet motor system consists of two integrated winding bearingless permanent magnet motors and their motor controllers, and one axial magnetic bearing and its controller. The integrated winding bearingless permanent magnet motors are used to realize the system's X / Y degree of freedom, and the axial magnetic bearing is used to realize the system's Z degree of freedom.

[0087] The following design uses a bearingless permanent magnet motor with 4 pole pairs (8 poles) as an example. The specific design process and the torque performance verification of the designed bearingless permanent magnet motor are shown below:

[0088] Step 1: Determine the number of unit motors in the bearingless permanent magnet motor relative to the torque winding. For a 4-pole rotor permanent magnet motor, analyze the number of pole pairs of the magnetic field generated by its torque and levitation current to achieve stable levitation of the motor, thereby determining the number of unit motors in the bearingless permanent magnet motor relative to the torque winding.

[0089] In existing technologies, based on the principle of levitation force generation, the number of pole pairs in the levitation winding is fixed. If the number of pole pairs of the rotor is P, then the number of pole pairs in the levitation winding is P±1. To realize a bearingless permanent magnet motor with a 4-pole rotor, the number of pole pairs in the levitation winding is usually 3 or 5.

[0090] In this embodiment, a permanent magnet motor with 4 pole pairs is regarded as a unit motor with 2 pole pairs. Thus, for a permanent magnet motor with 4 pole pairs, the number of pole pairs of its levitation winding can be selected as 2 pole pairs, that is, two sets of opposite pole pairs of stator windings can be used on the stator to generate levitation force.

[0091] If the entire motor consists of t2 units, then the magnetic field generated by the torque current is t1 = 2t2 pole pairs (relative to the torque winding, the entire motor consists of t1 units), and the magnetic field generated by the levitation current is t2 pole pairs. According to the conditions for generating levitation force, to generate stable levitation force, the number of pole pairs of the torque magnetic field and the levitation magnetic field must differ by 1, so 2t2 ± t2 = 1, therefore t1 = 2t2 = 2.

[0092] Step 2: Design the number of slots of the integrated winding according to the number of unit motors of the bearingless permanent magnet motor relative to the torque winding, so that it can generate a large and stable magnetomotive force, thereby giving the motor good electromagnetic characteristics and realizing stable rotation of the motor.

[0093] Based on the fractional-slot AC winding theory, the first calculation formula is obtained:

[0094]

[0095] When the distribution of slot numbers occupied by the three phases along the air gap circumference is periodic, the number of slots in each cycle constitutes a unit motor. If the motor has t1 cycles, then the motor can be regarded as t1 unit motors. There is a υ0 pole pair magnetomotive force harmonic within a unit motor, and the entire motor has a t1υ0 pole pair magnetomotive force harmonic.

[0096] A: To achieve stable torque, the motor needs to generate a large and stable magnetomotive force.

[0097] The combined magnetomotive force of the three-phase winding is

[0098]

[0099] K Nv =k qv k yv

[0100] N r k is the number of turns in the winding. yυ is the short-range coefficient of the magnetomotive force. Here, ω is the amplitude of the three-phase current, t is time, θ is the initial phase angle of the current, and k is the angular velocity of the motor current. qυ is the winding distribution coefficient of the magnetomotive force.

[0101] B: The pole slot structure of the motor affects N r k yυ , The θ parameter has a relatively small impact; the pole slot structure of the motor has little effect on k. qυ The magnitude of the fundamental winding distribution factor has a significant impact. Therefore, to achieve a large and stable magnetomotive force in the motor, a large fundamental winding distribution factor is required. Motors typically employ a 60° phase winding distribution.

[0102] The distribution factor of the υth harmonic phase winding in the 60° phase band is

[0103]

[0104] X represents the spatial distance between two adjacent positive slot numbers.

[0105] C: To determine the magnitude of the fundamental winding distribution coefficient, it is necessary to analyze the magnitudes of D, X, and N1. The values ​​of X and N1 are related to the magnitude of D, so it is necessary to determine the magnitude of D first. Based on the fact that the motor has 4 pole pairs (p=4) and the number of unit motors of the bearingless permanent magnet motor relative to the torque winding determined in step 1 (t1=2), the magnitude of D is obtained.

[0106] Based on the theory of AC windings, the second calculation formula is obtained:

[0107] When the denominator D of q is even, When the denominator D of q is odd,

[0108] Based on the conditions 2p = 8 and t1 = 2 obtained in step C, we can deduce that D = 4.

[0109] D: Determine the value of N1 based on the obtained value of D, and then determine the size of the slot pitch number X.

[0110] because Then Z = 6N1, N1 and D have no common divisor, D = 4, so N1 = 2n + 1, Z = 12n + 6, n = 0, 1, 2... The spatial distance between two adjacent positive slot numbers is:

[0111] n1 = 1, 2, 3...D, choose an appropriate integer such that [3N1(n1-1)+1] / D is an integer.

[0112] When n1 = 2n2, take n1 = 2, then X = 3n1 + 2 = 6n2 + 2, n2 = 0, 1, 2...;

[0113] When n1 = 2n2 + 1, take n1 = 4, then X = 9n1 + 5 = 18n2 + 14, n2 = 0, 1, 2...

[0114] E: Determine the magnitude of the fundamental winding distribution coefficient based on the obtained values ​​of D, X, and N1.

[0115] The distribution coefficient of υ=1 (fundamental wave) is

[0116] n is an even number

[0117] n is an odd number

[0118]

[0119]

[0120] It can be seen that the stator pole pairs formed by the 8-pole / (12n+6)-slot motor windings are 4. They mainly utilize the second harmonic to generate stable torque. Combining the principle of levitation force generation, the bearingless permanent magnet motor with integrated windings of 8 poles / (12n+6) slots can generate stable torque and stable levitation force.

[0121] The above is the design method for the number of poles and slots in an 8-pole integrated winding bearingless permanent magnet motor. This method is also applicable to the design of the number of poles and slots in an 8N-pole integrated winding bearingless permanent magnet motor. The corresponding pole-slot configuration for an 8N-pole integrated winding bearingless permanent magnet motor is 8N poles / 12n + 6 slots.

[0122] The method for determining the pole slots of the integrated winding bearingless permanent magnet motor in this embodiment has the following advantages:

[0123] Compared to traditional bearingless motors that require two sets of windings—torque windings and suspension windings—this design reduces slots, allowing for a more compact stator structure and ultimately, a more miniaturized motor. The derived pole-slot configuration of the integrated winding bearingless permanent magnet motor provides greater structural flexibility.

[0124] Compared to traditional magnetic levitation permanent magnet motors, the integrated winding bearingless permanent magnet motor system of this invention has a more compact overall structure, a simpler internal structure, and a higher power density, enabling better practical applications.

[0125] The present invention also provides a pole and slot determination system for an integrated winding bearingless permanent magnet motor. Figure 12 This is a schematic diagram of the pole and slot determination system for an integrated winding bearingless permanent magnet motor provided in an embodiment of the present invention. See also... Figure 12 The system includes:

[0126] The module 201 for determining the number of unit motors is used to determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding, based on the principle of generating levitation force of integrated winding.

[0127] The slot number range determination module 202 is used to determine the number of slots of the bearingless permanent magnet motor to be designed based on AC winding theory, according to the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors.

[0128] The bearingless permanent magnet motor design module 203 is used to obtain a bearingless permanent magnet motor based on the number of pole pairs and the number of slots of the rotor.

[0129] In one example, the unit motor number determination module 201 specifically includes:

[0130] The unit for determining the number of unit motors is used to determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding as 2 if the number of pole pairs of the rotor is p; where p = 4N, N = 3a ± 1, a = 0, 1, 2...

[0131] In one example, the slot number range determination module 202 specifically includes:

[0132] The calculation formula determination unit is used to determine the first calculation formula and the second calculation formula by using AC winding theory, based on the number of pole pairs of the rotor and the number of unit motors.

[0133] The first calculation formula is:

[0134]

[0135] q represents the number of slots per pole per phase; Z represents the number of slots in the bearingless permanent magnet motor to be designed; p represents the number of pole pairs of the rotor. After simplification, it becomes N1 is the numerator after simplification; D is the denominator after simplification; when q represents the integer slot, D = 1, N1 = q; when q represents the fraction slot, D ≠ 1, and N1 and D have no common divisor.

[0136] The second calculation formula is:

[0137]

[0138] t1 represents the number of motors in the unit.

[0139] The unit for determining the denominator value after simplification is used to substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of motors in the unit into the second calculation formula to obtain the value of the denominator after simplification.

[0140] The slot number determination unit is used to substitute the value of the denominator after simplification and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

[0141] In one example, the bearingless permanent magnet motor to be designed has 12n+6 slots; where n≥0 and n is an integer.

[0142] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0143] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for determining the pole slots of an integrated winding bearingless permanent magnet motor, characterized in that, include: Based on the principle of levitation force generation of integrated windings, the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding is determined. Based on AC winding theory, the number of slots of the bearingless permanent magnet motor to be designed is determined according to the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors. A bearingless permanent magnet motor is obtained based on the number of pole pairs and the number of slots of the rotor; The determination of the number of unit motors relative to the torque winding of the bearingless permanent magnet motor to be designed, based on the principle of levitation force generation of integrated windings, specifically includes: If the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed is p Therefore, the number of unit motors relative to the torque winding in the bearingless permanent magnet motor to be designed is determined to be 2; where, p= 4 N , N =3 a ±1 ，a =0, 1, 2…; The method based on AC winding theory determines the number of slots in the bearingless permanent magnet motor to be designed according to the number of pole pairs of the rotor and the number of unit motors. Specifically, this includes: Using AC winding theory, the first calculation formula and the second calculation formula are determined by the number of pole pairs of the rotor and the number of unit motors; The first calculation formula is: ； q The number of slots per pole per phase; Z The number of slots for the bearingless permanent magnet motor to be designed; p is the number of pole pairs of the rotor; After simplification, it becomes ; N 1 is the numerator after simplification; D The denominator after simplification; when q When representing integer slots, D =1, N 1= q ;when q When representing fractional slots, D≠1, and N 1 and D No common divisor; The second calculation formula is: ； t 1 represents the number of motors in the unit; Substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors into the second calculation formula to obtain the value of the denominator after simplification; Substitute the simplified denominator value and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

2. The method for determining the pole slots of an integrated winding bearingless permanent magnet motor according to claim 1, characterized in that, The bearingless permanent magnet motor to be designed has 12 slots. n +6; among which, n ≥0, and n It is an integer.

3. A pole and slot determination system for an integrated winding bearingless permanent magnet motor, characterized in that, include: The module for determining the number of unit motors is used to determine the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding, based on the principle of generating levitation force of integrated windings. The slot number range determination module is used to determine the number of slots of the bearingless permanent magnet motor to be designed based on AC winding theory, according to the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors. A bearingless permanent magnet motor design module is used to obtain a bearingless permanent magnet motor based on the number of pole pairs and the number of slots of the rotor; The module for determining the number of motors in a unit specifically includes: The unit for determining the number of unit motors is used to determine that if the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed is p, then the number of unit motors of the bearingless permanent magnet motor to be designed relative to the torque winding is 2; where, p= 4 N , N =3 a ±1 ，a =0, 1, 2…; The module for determining the range of slot numbers specifically includes: The calculation formula determination unit is used to determine the first calculation formula and the second calculation formula by using AC winding theory, based on the number of pole pairs of the rotor and the number of unit motors. The first calculation formula is: ； q The number of slots per pole per phase; Z The number of slots for the bearingless permanent magnet motor to be designed; p is the number of pole pairs of the rotor; After simplification, it becomes ; N 1 is the numerator after simplification; D The denominator after simplification; when q When representing integer slots, D =1, N 1= q ;when q When representing fractional slots, D≠1, and N 1 and D No common divisor; The second calculation formula is: ； t 1 represents the number of motors in the unit; The unit for determining the denominator value after simplification is used to substitute the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed and the number of unit motors into the second calculation formula to obtain the value of the denominator after simplification. The slot number determination unit is used to substitute the value of the denominator after simplification and the number of pole pairs of the rotor of the bearingless permanent magnet motor to be designed into the first calculation formula to determine the number of slots of the bearingless permanent magnet motor to be designed.

4. The pole slot determination system for an integrated winding bearingless permanent magnet motor according to claim 3, characterized in that, The bearingless permanent magnet motor to be designed has 12 slots. n +6; among which, n ≥0, and n It is an integer.

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