Dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density

Abstract

The invention discloses a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density. The dual three-phase permanent magnet synchronous motor comprises a rotor and a stator, the rotor mainly comprises a rotor yoke, magnetic steel and a non-magnetic sheath; the stator mainly comprises a stator core and two sets of windings; the magnetic steel is adhered to the rotor yoke through epoxy glue, and the non-magnetic sheath is installed on the outer circle of the magnetic steel through cold pressing and glue joint. And the two sets of windings are embedded into the stator core according to a specific rule. Large and stable torque can be output in a limited space, meanwhile, the fault tolerance of the motor is improved, and the motor has the advantages of being high in torque density, low in interference and high in reliability. A motor stator winding is innovatively designed, an independent double three-phase design is adopted in a topological structure, a short-distance concentrated winding is adopted in an arrangement mode, and the reliability and the torque density of the motor are improved; sinusoidal optimization design is carried out on the arrangement mode and size of rotor magnetic steel, so that back electromotive force harmonics are reduced, and the operation stability of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the field of permanent magnet synchronous motors, and in particular to a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density. It is necessary to achieve basic electromagnetic performance under limited volume and weight, and also have the characteristics of high reliability, high density, high redundancy, etc., for aerospace permanent magnet synchronous motors. Background Art

[0002] High-performance permanent magnet motors for aerospace applications face great technical challenges: the motor's fault tolerance and torque density need to be improved. Traditional aerospace motors use dual redundancy to improve the motor's fault tolerance, which is inconsistent with the increase in the motor's torque density under the same volume. The motor volume can only be further increased, causing problems for motor applications. Aerospace motors not only need to achieve basic electromagnetic performance under limited volume and weight, but also have the characteristics of high reliability, high density, high redundancy, and low power consumption. Therefore, aerospace motor-related technologies are recognized as technical problems in China and even internationally. Summary of the invention

[0003] The technical problem solved by the present application is: to overcome the deficiencies of the prior art and provide a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, which can output a large and stable torque in a limited space, while improving the fault tolerance of the motor, and has the characteristics of high torque density, low interference and high reliability.

[0004] The technical solutions provided by this application are as follows:

[0005] A dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density comprises a stator and a rotor, wherein the stator is sleeved on the outer side of the rotor; the rotor mainly comprises a rotor yoke, a magnetic steel and a non-magnetic sleeve, an annular groove is arranged on the outer circumferential surface of the rotor yoke, and the magnetic steel is fully assembled along the circumferential direction of the annular groove and arranged in the annular groove; the non-magnetic sleeve is sleeved on the outside of the rotor yoke and the magnetic steel;

[0006] The stator includes a stator core and a winding. The stator core is provided with a plurality of stator teeth. A winding slot is formed between any two adjacent stator teeth. The winding is wound around the stator teeth through the stator teeth.

[0007] The number of magnetic steels is the number of poles of the motor, the number of winding slots is the number of slots of the motor, and the number of slots / number of stages = 0.8-1.5.

[0008] The inner wall surface and the outer wall surface of each magnetic steel are arc-shaped surfaces, and the diameter of the circle where the inner wall surface of each magnetic steel is located is not equal to the diameter of the circle where the outer wall surface is located.

[0009] The diameter of the circle where the inner wall surface of the magnetic steel is located is equal to the diameter of the annular groove, and the diameter of the circle where the outer wall surface of the magnetic steel is located is smaller than the diameter of the circle where the inner wall surface of the magnetic steel is located.

[0010] The windings are arranged in two sets, the topological structures of the two sets of windings are both independent dual three-phase, and the arrangement method is both short-distance concentrated windings.

[0011] The two sets of windings are respectively a first set of three-phase windings and a second set of three-phase windings. The first set of three-phase windings includes three groups of windings, which are evenly distributed in the circumferential direction of the stator core. The second set of three-phase windings includes three groups of windings, which are evenly distributed in the circumferential direction of the stator core.

[0012] The three groups of windings of the first set of three-phase windings correspond one to one with the three groups of windings of the second set of three-phase windings, and the electrical angle difference between one group of windings of the first set of three-phase windings and one group of windings of the second set of three-phase windings is 30°.

[0013] In summary, this application at least includes the following beneficial technical effects:

[0014] The present invention discloses a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, which can output a large and stable torque in a limited space, while improving the fault tolerance of the motor, and has the characteristics of high torque density, low interference and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram of a rotor in an embodiment of the present invention;

[0016] Figure 2 Schematic diagram of the stator in the embodiment of the present invention

[0017] Figure 3 This is a schematic diagram of winding embedding in an embodiment of the present invention;

[0018] Description of the accompanying figures: 1. Rotor;

[0019] 11. rotor yoke; 12. magnetic steel; 13. non-magnetic sheath;

[0020] 2. Stator;

[0021] 21. Stator core; 22. Winding. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0023] The present application embodiment discloses a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, such as Figure 1 and Figure 2 Shown, including

[0024] The present invention can output a relatively large and stable torque in a limited space, while improving the fault tolerance of the motor, and has the characteristics of high torque density, low interference and high reliability.

[0025] The dual three-phase permanent magnet synchronous motor comprises a stator 2 and a rotor 1, wherein the stator 2 is sleeved on the outer side of the rotor 1.

[0026] like Figure 2 As shown, the stator 2 includes a stator core 21 and two sets of windings 22. The stator core 21 is provided with a plurality of stator teeth. A winding slot is formed between any two adjacent stator teeth. The two sets of windings are embedded in the winding slots of the stator core according to a specific rule.

[0027] The topological structure of the two sets of windings 22 adopts independent dual three-phase, and the arrangement adopts short-distance concentrated winding to improve the reliability and torque density of the motor. The two sets of windings are respectively the first set of three-phase windings and the second set of three-phase windings. The first set of three-phase windings includes three groups of windings, and the three groups of windings are evenly distributed in the circumferential direction of the stator core. The second set of three-phase windings includes three groups of windings, and the three groups of windings are evenly distributed in the circumferential direction of the stator core. The three groups of windings of the first set of three-phase windings correspond to the three groups of windings of the second set of three-phase windings one by one, and the difference between one group of windings of the corresponding first set of three-phase windings and one group of windings of the second set of three-phase windings is 30° electrical angle.

[0028] The rotor magnetic steel layout and size are sinusoidally optimized to reduce back EMF harmonics and improve motor operation stability.

[0029] like Figure 1 As shown, the rotor 1 mainly includes a rotor yoke 11, a magnetic steel 12 and a non-magnetic sleeve 13. The outer circumferential surface of the rotor yoke 11 is provided with an annular groove. The magnetic steel 12 is arranged in the annular groove by full circumference. The inner wall surface and outer wall surface of each magnetic steel are arc-shaped surfaces, and the inner and outer diameters of each magnetic steel are not concentric. The inner wall surface of the magnetic steel fits the bottom of the annular groove of the rotor yoke, that is, the diameter of the circle where the inner wall surface of the magnetic steel is located is equal to the diameter of the annular groove, and the diameter of the circle where the outer wall surface of the magnetic steel is located is smaller than the diameter of the circle where the inner wall surface of the magnetic steel is located. It can improve the processing efficiency and the sinusoidality of the air gap magnetic field. The non-magnetic sleeve 13 is installed on the outer circle of the magnetic steel by cold pressing and gluing to wrap the magnetic steel, which can reduce the risk of magnetic steel collision and excess adsorption.

[0030] like Figure 2As shown, the motor adopts a 20-pole 24-slot design, that is, the number of poles of the motor is 20, that is, 20 magnetic steels are embedded on the outer circumferential surface of the rotor yoke; the number of winding slots is 24 slots, and by embedding two sets of windings with a certain slot number (5 slot numbers in this patent) in the stator core, an electrically independent double three-phase winding with a corresponding phase sequence difference of 30° electrical angle can be obtained. It can make the six phases work simultaneously with higher average torque and lower torque pulsation. Under normal working conditions of the motor, the two sets of windings run in parallel and synthesize a large torque output. If the whole machine product diagnosis finds that an individual winding fault occurs, the fault diagnosis strategy can be used to switch to working with only healthy three-phase windings; when both sets of windings have partial coil faults, the remaining healthy phase windings can be recombined to form a multi-phase motor, which greatly improves the fault-tolerant operation capability of the system.

[0031] The motor adopts a near-pole-slot combination (the number of poles and slots is close, this patent is 20 poles and 24 slots), and the winding arrangement is a short-distance concentrated winding, which can greatly shorten the winding end, reduce the amount of copper and winding loss, and improve the motor efficiency. At the same time, the axial length of the entire motor is reduced and the torque density is improved. Through the special pole-slot combination and the independent design of the two sets of windings, the magnetic and thermal coupling between the windings is greatly reduced, the independence of each set of three-phase windings is improved, and the reliability of the motor is effectively improved.

[0032] like Figure 3As shown in FIG. 1 , a winding method of a group of windings of the first set of three-phase windings or the second set of three-phase windings is as follows: an i+1th winding slot is between the i-th stator tooth and the i+1th stator tooth; an end of the winding extends from the bottom end of the i-th winding slot to form a connection terminal, the winding enters from the bottom end of the i-th winding slot and exits from the top end of the i-th winding slot, then enters from the top end of the i-th winding slot into the i+1th winding slot and exits from the bottom end of the i+1th winding slot, and then continues from the i+1th winding slot to the top end of the i-th winding slot. The bottom end of the winding slot is inserted into the bottom end of the i-th winding slot, and the winding form is repeated to wind the set number of turns on the i+1 stator tooth; then, the winding is inserted from the bottom end of the i+1 winding slot to the bottom end of the i+2 winding slot and out from the top of the i+2 winding slot, then inserted from the top of the i+1 winding slot and out from the bottom end of the i+1 winding slot, and then continues to penetrate from the bottom end of the i+2 winding slot, and repeats the winding form to wind the set number of turns on the i+2 stator tooth. number; then, the winding passes from the bottom end of the i+1th winding slot to the bottom end of the i+nth winding slot, and passes out from the top end of the i+nth winding slot, n is an integer greater than 4, then passes from the top end of the i+nth winding slot to the top end of the i+n-1th winding slot, and passes out from the bottom end of the i+n-1th winding slot, and then continues to pass through the bottom end of the i+nth winding slot, repeating this winding form to wind a set number of turns on the i+nth stator tooth; then, the winding passes from the i+n-1th winding slot to the top end of the i+n-1th winding slot, and then passes out from the bottom end of the i+n-1th winding slot, and then continues to pass through the bottom end of the i+nth winding slot, repeating this winding form to wind a set number of turns on the i+nth stator tooth; then, the winding passes from the i+n-1th winding slot to the top end of the i+n-1th winding slot, and then passes out from the top end of the i+n-1th winding slot, and then passes through from the top end of the i+n-1th winding slot, and then passes through from the top end of the i+n-1th winding slot, and then passes from the top end of the i+n-1th winding slot to ... The bottom end of the i+n+1th winding slot is inserted into the bottom end of the i+n+1th winding slot, and exits from the top of the i+n+1th winding slot, then enters from the top of the i+n+2th winding slot and exits from the bottom end of the i+n+2th winding slot, and then continues to insert into the bottom end of the i+n+1th winding slot, repeating this winding form to wind a set number of turns on the i+n+1th stator tooth; thereafter, the winding exits from the bottom end of the i+n+2th winding slot and repeats the above winding method across multiple stator teeth.

[0033] If the number of winding slots is x, the winding slots include the first winding slot, the second winding slot, the third winding slot, ... the xth winding slot. i∈[1, x]. When i+n>x, the next value after x is 1.

[0034] The present invention can output a large and stable torque in a limited space, while improving the fault tolerance of the motor, and has the characteristics of high torque density, low interference, and high reliability. The motor stator winding is innovatively designed, the topology adopts an independent dual three-phase design, and the arrangement adopts a short-distance concentrated winding to improve the reliability and torque density of the motor; the rotor magnetic steel layout and size are sinusoidally optimized to reduce back-EMF harmonics and improve the stability of motor operation.

[0035] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0036] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, characterized in that: The invention comprises a stator (2) and a rotor (1), wherein the stator (2) is sleeved on the outside of the rotor (1); the rotor (1) mainly comprises a rotor yoke (11), a magnetic steel (12) and a non-magnetic sleeve (13); an annular groove is arranged on the outer circumferential surface of the rotor yoke (11); the magnetic steel (12) is arranged in a circular manner along the circumferential direction of the annular groove and is arranged in the annular groove; and the non-magnetic sleeve (13) is sleeved on the outside of the rotor yoke (11) and the magnetic steel (12); The stator (2) comprises a stator core (21) and a winding (22), wherein the stator core (21) is provided with a plurality of stator teeth, a winding slot is formed between any two adjacent stator teeth, and the winding (22) is wound around the stator teeth through the stator teeth; The number of magnetic steels (12) is the number of poles of the motor, the number of winding slots is the number of slots of the motor, and the number of slots / number of stages=0.8-1.

5.

2. According to claim 1, a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, characterized in that: The inner wall surface and the outer wall surface of each magnetic steel (12) are both arc-shaped surfaces, and the diameter of the circle where the inner wall surface of each magnetic steel (12) is located is not equal to the diameter of the circle where the outer wall surface is located.

3. According to claim 2, a dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density, characterized in that: The diameter of the circle where the inner wall surface of the magnetic steel (12) is located is equal to the diameter of the annular groove, and the diameter of the circle where the outer wall surface of the magnetic steel (12) is located is smaller than the diameter of the circle where the inner wall surface of the magnetic steel (12) is located.

4. The low-disturbance, high-reliability, high-torque-density dual three-phase permanent magnet synchronous motor according to claim 1, characterized in that: The windings are arranged in two sets, the topological structures of the two sets of windings are both independent three-phase sequences, and the arrangement method is both short-distance concentrated windings.

5. The dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density according to claim 4 is characterized in that: The two sets of windings are respectively a first set of three-phase windings and a second set of three-phase windings, the first set of three-phase windings comprising three groups of windings, the three groups of windings being evenly distributed in the circumferential direction of the stator core (21), and the second set of three-phase windings comprising three groups of windings, the three groups of windings being evenly distributed in the circumferential direction of the stator core (21).

6. The dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density according to claim 5 is characterized in that: The three groups of windings of the first set of three-phase windings correspond one to one with the three groups of windings of the second set of three-phase windings, and the electrical angle difference between one group of windings of the first set of three-phase windings and one group of windings of the second set of three-phase windings is 30°.

7. The dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density according to claim 1 is characterized in that: The number of winding slots is x, i∈[1,x]. When i+n>x, the next value after x is 1; The winding method of a group of windings of the first set of three-phase windings or the second set of three-phase windings is as follows: the i+1th winding slot is between the i-th stator tooth and the i+1th stator tooth; the end of the winding extends from the bottom end of the i-th winding slot to form a terminal, and the winding is wound on the i+1th stator tooth and the i+2th stator tooth in sequence according to the first winding method; the winding crosses multiple stator teeth and is wound on the i+nth stator tooth and the i+n+1th stator tooth in sequence according to the second winding method, where n is the number of stator teeth crossed + 2; then the winding continues to cross multiple stator teeth and continues to be wound between two adjacent stator teeth in sequence according to the first winding method, crosses multiple stator teeth, and is wound between two adjacent stator teeth in sequence according to the second winding method, and finally extends to form an output terminal.

8. The dual three-phase permanent magnet synchronous motor with low disturbance, high reliability and high torque density according to claim 7, characterized in that: The first winding method includes: the winding enters from the bottom end of the i-th winding slot and exits from the top end of the i-th winding slot, then enters from the top end of the i-th winding slot into the i+1-th winding slot and exits from the bottom end of the i+1-th winding slot, then continues to enter from the bottom end of the i+1-th winding slot to the bottom end of the i-th winding slot, repeats this winding form and winds a set number of turns on the i+1-th stator tooth; thereafter, the winding enters from the bottom end of the i+1-th winding slot to the bottom end of the i+2-th winding slot and exits from the top end of the i+2-th winding slot, then enters from the top end of the i+1-th winding slot and exits from the bottom end of the i+1-th winding slot, then continues to enter from the bottom end of the i+2-th winding slot, repeats this winding form and winds a set number of turns on the i+2-th stator tooth; The second winding method is: the winding passes from the bottom end of the i+1th winding slot to the bottom end of the i+nth winding slot and passes out from the top end of the i+nth winding slot, where n is an integer greater than 4, and then passes from the top end of the i+nth winding slot to the top end of the i+n-1th winding slot and passes out from the bottom end of the i+n-1th winding slot, and then continues to pass into the bottom end of the i+nth winding slot, and repeats this winding form in the i+nth stator. The winding is wound on the tooth for a set number of turns; thereafter, the winding passes from the bottom end of the i+n-1th winding slot to the bottom end of the i+n+1th winding slot, and comes out from the top end of the i+n+1th winding slot, then passes from the top end of the i+n+2th winding slot and comes out from the bottom end of the i+n+2th winding slot, and then continues to pass into the bottom end of the i+n+1th winding slot, and repeats this winding form to wind a set number of turns on the i+n+1th stator tooth.

Images