阅读说明：本技术 一种具有不对称定子极的混合励磁型磁通反向电机 (Hybrid excitation type magnetic flux reverse motor with asymmetric stator poles ) 是由 阳辉 刘杨阳 林鹤云 于 2019-10-24 设计创作，主要内容包括：本发明公开了一种具有不对称定子极的混合励磁型磁通反向电机，包括定子、转子、三相电枢绕组、单相励磁绕组和不导磁转轴，转子包括转子齿和转子轭，转子轭固定在不导磁转轴上，转子齿沿转子轭周向均匀设置，定子位于转子的转子齿外部，与转子齿之间有一点间隙，定子包括定子轭、定子电枢齿、定子励磁齿和永磁体，定子电枢齿和定子励磁齿沿定子周向交替设置，且每个定子电枢齿下端位于定子电枢齿铁心两侧设有两块同极性的永磁体，三相电枢绕组缠绕于定子电枢齿上，单相励磁绕组缠绕于定子励磁齿上。本发明采用双凸极结构，结构简单，鲁棒性强，适合交流无刷运行，同时混合励磁的引入实现了气隙磁通的可调，提升了电机的转速范围。(The invention discloses a mixed excitation type flux reversal motor with asymmetric stator poles, which comprises a stator, a rotor, three-phase armature windings, a single-phase excitation winding and a non-magnetic rotating shaft, wherein the rotor comprises rotor teeth and a rotor yoke, the rotor yoke is fixed on the non-magnetic rotating shaft, the rotor teeth are uniformly arranged along the circumferential direction of the rotor yoke, the stator is positioned outside the rotor teeth of the rotor and has a little gap with the rotor teeth, the stator comprises a stator yoke, stator armature teeth, stator excitation teeth and permanent magnets, the stator armature teeth and the stator excitation teeth are alternately arranged along the circumferential direction of the stator, the lower end of each stator armature tooth is positioned at two sides of an iron core of the stator armature teeth and is provided with two permanent magnets with the same polarity, the three-phase armature windings are wound on the stator armature teeth, and the single-phase excitation windings are wound on the stator excitation teeth. The invention adopts a double salient pole structure, has simple structure and strong robustness, is suitable for alternating current brushless operation, realizes the adjustment of air gap magnetic flux by introducing mixed excitation, and improves the rotating speed range of the motor.)

1. A mixed excitation type magnetic flux reversal motor with asymmetric stator poles is characterized by comprising a stator (1), a rotor (2), a three-phase armature winding (3), a single-phase excitation winding (4) and a non-magnetic-conductive rotating shaft (5), wherein the rotor comprises rotor teeth (2.1) and a rotor yoke (2.2), the rotor yoke is fixed on the non-magnetic-conductive rotating shaft, the rotor teeth are uniformly arranged along the circumferential direction of the rotor yoke, the stator is positioned outside the rotor teeth of the rotor, a little clearance is left between the stator and the rotor teeth, the stator comprises a stator yoke (1.1), a stator armature tooth (1.2), a stator excitation tooth (1.3) and a permanent magnet (1.4), the stator armature tooth and the stator excitation tooth are alternately arranged along the circumferential direction of the stator, and the lower end of each stator armature tooth is positioned at two sides of the stator armature tooth iron core and is provided with two permanent magnets with the same polarity, a three-phase armature winding is wound on the stator armature teeth, and a single-phase excitation winding is wound on the stator excitation teeth.

2. A hybrid excitation flux reversing motor having asymmetric stator poles according to claim 1, wherein the width of the stator armature teeth is greater than the width of the stator field teeth.

3. A hybrid excitation-type flux-reversing motor having asymmetric stator poles as claimed in claim 1, wherein the stator armature teeth and the stator excitation teeth are of inverted "T" type structure, wherein the elongated structure of the inverted "T" type structure body is integrally connected to the stator yoke, and a gap is formed between the protruding portions on both sides of the lower portion of the inverted "T" type structure body and the rotor teeth.

4. A hybrid excitation flux reversing motor with asymmetric stator poles according to claim 3, wherein the stator teeth are formed with slots for holding permanent magnets on the protruding portions of both sides of the lower portion of the inverted "T" shaped structural body.

5. A hybrid excitation flux reversing motor having asymmetric stator poles according to claim 1, wherein the permanent magnets are high coercivity rare earth permanent magnets, the direction of magnetization is radial and the polarity of the permanent magnets on adjacent stator armature teeth is the same.

6. A hybrid excitation-type flux reversing motor having asymmetric stator poles as claimed in claim 1, wherein the three-phase armature winding and the single-phase field winding are concentrated windings sharing the stator slot spaces formed by adjacent stator armature teeth and stator field teeth.

7. A hybrid excitation flux reversing motor having asymmetric stator poles according to claim 1, wherein the single phase field windings wound around each stator field tooth are energized in the same direction.

8. A hybrid excitation flux reversing motor having asymmetric stator poles according to claim 1, wherein both the stator and rotor are salient pole structures.

Technical Field

The invention relates to a hybrid excitation motor, in particular to a hybrid excitation type magnetic flux reversal motor with asymmetric stator poles, and belongs to the technical field of permanent magnet motors.

Background

The conventional Permanent Magnet Synchronous Motor (PMSM) has the advantages of high power density, high efficiency, reliable operation, strong overload capacity and the like due to the adoption of rare earth Permanent Magnet materials (such as neodymium iron boron), and is an important development direction of motor disciplines. With the development of rare earth permanent magnet materials and power electronic technology, PMSM has been applied in a large scale in various fields of aerospace, national defense, industrial and agricultural production and daily life.

However, the conventional permanent magnet synchronous motor has a serious problem that the air gap magnetic field cannot be adjusted, and the air gap magnetomotive force is provided mainly by the residual magnetism after the permanent magnet is magnetized, which is different from the electrically excited synchronous motor and is difficult to change the air gap magnetic field. Therefore, the traditional PMSM is limited in speed regulation range during operation, and the output characteristic is difficult to adjust, so that the realization of the adjustability of the air gap field of the PMSM is a research hotspot in the field of permanent magnet motors.

In order to realize the adjustability of an air gap magnetic field, a plurality of hybrid excitation motors taking a rotor permanent magnet type motor as a prototype appear, wherein the structure of series connection of electric excitation magnetic flux and permanent magnet magnetic flux can cause the excitation efficiency of electric excitation to be remarkably reduced, and the excitation loss of the electric excitation can also be increased. In contrast, a hybrid excitation motor based on a stator permanent magnet type motor has a significant advantage in structural complexity. The method not only ensures the advantages of adjustability of the magnetic field combined with electric excitation and high torque density of permanent magnet excitation, but also is relatively simple and has higher robustness.

Disclosure of Invention

The purpose of the invention is as follows: in order to solve the problems that the speed regulation range of the traditional flux reversal permanent magnet motor is not high and the flux weakening capability is limited, the invention provides a hybrid excitation type flux reversal motor with asymmetric stator poles.

The technical scheme is as follows: in order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a mixed excitation type magnetic flux reverse motor with asymmetric stator poles, which comprises a stator, a rotor, three-phase armature windings, a single-phase excitation winding and a non-magnetic rotating shaft, wherein the rotor comprises rotor teeth and a rotor yoke, the rotor yoke is fixed on the non-magnetic rotating shaft, the rotor teeth are uniformly arranged along the circumferential direction of the rotor yoke, the stator is positioned outside the rotor teeth of the rotor and has a little gap with the rotor teeth, the stator comprises a stator yoke, stator armature teeth, stator excitation teeth and permanent magnets, the stator armature teeth and the stator excitation teeth are alternately arranged along the circumferential direction of the stator, the lower end of each stator armature tooth is positioned at two sides of an iron core of the stator armature teeth and is provided with two permanent magnets with the same polarity, the three-phase armature windings are wound on the stator armature teeth, and the single-phase excitation windings are wound on the stator excitation teeth. The rotor has no permanent magnet or excitation winding, and the permanent magnet, the armature winding and the excitation winding are all arranged on the stator, so that the heat dissipation of the permanent magnet and the winding is facilitated. Meanwhile, the electro-magnetic circuit and the permanent-magnetic circuit are parallel, so that the electro-magnetic excitation is easier, the electro-magnetic flux is increased, the electro-magnetic loss is reduced, the magnetic adjusting range is expanded, and the possibility of irreversible demagnetization of the permanent magnet caused by the fact that the directions of the electro-magnetic flux and the permanent-magnetic flux are opposite is reduced.

Preferably, the width of the stator armature teeth is greater than the width of the stator field teeth. The stator armature teeth are the main path of main magnetic flux of a turn chain of the three-phase alternating-current winding, so the width is required to be wider; the stator excitation teeth on the two sides of the stator armature teeth are responsible for the main passage of the electric excitation magnetic flux, and isolate two adjacent armature teeth and the armature windings wound on the two adjacent armature teeth to a certain extent, so that the coupling of the adjacent armature windings is reduced. In addition, compared with stator teeth with equal width, the design has better parameter optimization selection space, and is beneficial to realizing pursuit of higher performance optimization.

Preferably, the stator armature teeth and the stator excitation teeth are of inverted T-shaped structures, wherein the long strip-shaped structure of the inverted T-shaped structure body is integrally connected with the stator yoke, and a certain gap is formed between the protruding parts on two sides of the lower part of the inverted T-shaped structure body and the rotor teeth.

Preferably, the protruding parts on two sides of the lower part of the stator armature tooth inverted T-shaped structure body are respectively provided with a groove for placing the permanent magnet.

Preferably, the permanent magnet is a high-coercivity rare earth permanent magnet, the magnetizing direction is radial, and the polarities of the permanent magnets on the armature teeth of adjacent stators are the same. The rare earth permanent magnet with high magnetic energy product can provide larger air gap flux density and higher torque density, and the electric excitation is used as a regulator of the air gap field of the motor, thereby realizing the continuous adjustment of the magnetic flux of the motor and improving the rotating speed range of the motor.

Preferably, the three-phase armature winding and the single-phase excitation winding are both concentrated windings and share the stator slot space formed by the adjacent stator armature teeth and the stator excitation teeth.

Preferably, the single-phase excitation winding wound on each stator excitation tooth is electrified in the same direction.

Preferably, the stator and the rotor are both salient pole structures. The structure is simple, firm and strong in robustness.

Has the advantages that: compared with the prior art, the invention has the following advantages:

(1) the permanent magnet, the armature winding and the excitation winding are all arranged on the stator, so that the heat dissipation of the permanent magnet and the winding is facilitated. The rotor is the same as a salient pole rotor of the switched reluctance motor, and has simple and firm structure and strong robustness.

(2) The electro-magnetic excitation magnetic circuit and the permanent-magnetic excitation main magnetic circuit are parallel, so that the electro-magnetic excitation is easier, the electro-magnetic flux is increased, the electro-magnetic excitation loss is reduced, the magnetic regulation range is expanded, and the possibility of irreversible demagnetization of permanent magnets caused by the fact that the directions of the electro-magnetic flux and the permanent-magnetic flux are opposite is reduced.

(3) The invention adopts a mixed excitation mode combining electric excitation and permanent magnet excitation, the rare earth permanent magnet with high magnetic energy product can provide larger air gap flux density and higher torque density, the electric excitation is used as a regulator of the air gap field of the motor, the continuous adjustment of the magnetic flux of the motor is realized, the rotating speed range of the motor is improved, and the motor has wide application prospect in the fields of electric automobiles and the like.

Drawings

FIG. 1 is a cross-sectional view of an electric machine of the present invention;

FIG. 2 is a magnetic flux distribution plot of the motor of the present invention with the single-phase field winding not energized;

FIG. 3 is a magnetic flux distribution plot of the single phase field winding of the motor of the present invention when energized in the forward direction;

FIG. 4 is a magnetic flux distribution plot of the single phase field winding of the motor of the present invention when energized in reverse;

in the figure: stator 1, rotor 2, three-phase armature winding 3, single-phase excitation winding 4, pivot 5, stator yoke 1.1, stator armature tooth 1.2, stator excitation tooth 1.3, permanent magnet 1.4, rotor tooth 2.1, rotor yoke 2.2.

Detailed Description

The present invention is further described in the following examples, which are intended to be illustrative only and not to be limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalent modifications thereof which would occur to persons skilled in the art upon reading the present specification and which are intended to be within the scope of the present invention as defined in the appended claims.

As shown in fig. 1, the hybrid excitation type flux-reversing motor having asymmetric stator poles of the present embodiment includes a stator 1, a rotor 2, a three-phase armature winding 3, a single-phase field winding 4, and a non-magnetic rotating shaft 5. The stator 1 and the rotor 2 are both in a salient pole structure, the rotor is fixed on the non-magnetic rotating shaft, and the stator is positioned outside the rotor. The rotor 2 comprises rotor teeth 2.1 and rotor yokes 2.2, the rotor yokes are fixed on the non-magnetic rotating shaft, the rotor teeth are uniformly distributed along the circumferential direction of the rotor yokes, and the rotor is not provided with permanent magnets or excitation windings. The stator 1 consists of a stator yoke 1.1, a stator armature tooth 1.2, a stator excitation tooth 1.3 and a permanent magnet 1.4, and has two types of stator teeth with different tooth widths, namely a stator armature tooth 1.2 with a larger width and a stator excitation tooth 1.3 with a smaller width. The stator armature teeth are the main path of main magnetic flux of a turn chain of the three-phase alternating-current winding, so the width is required to be wider; the stator excitation teeth on the two sides of the stator armature teeth are responsible for the main passage of the electric excitation magnetic flux, and isolate two adjacent armature teeth and the armature windings wound on the two adjacent armature teeth to a certain extent, so that the coupling of the adjacent armature windings is reduced. In addition, compared with stator teeth with equal width, the design has better parameter optimization selection space, and is beneficial to realizing pursuit of higher performance optimization. The stator armature teeth and the stator excitation teeth are of inverted T-shaped structures, wherein the long strip-shaped structures of the inverted T-shaped structure bodies are integrally connected with the stator yokes, certain gaps are formed between the protruding parts on the two sides of the lower portions of the inverted T-shaped structure bodies and the rotor teeth, and grooves for placing permanent magnets are formed in the protruding parts on the two sides of the lower portions of the inverted T-shaped structure bodies of the stator armature teeth respectively. Stator slots are formed between adjacent stator armature teeth, stator field teeth and stator yokes.

The permanent magnet 1.4 adopts neodymium iron boron permanent magnets, the magnetizing direction is radial, two neodymium iron boron permanent magnets 1.4 with the same polarity are attached to the left side and the right side of the lower end of the stator armature tooth 1.2, a stator armature tooth 1.2 iron core is arranged between the two permanent magnets 1.4, no permanent magnet is arranged below the stator excitation tooth 1.3, the polarities of the permanent magnets 1.4 on the adjacent armature teeth 1.2 are also the same, the distribution rule of NFeN-Fe-NFeN-Fe or SFeS-Fe-SFeS-Fe is presented when the area where the permanent magnet 1.4 is located is seen along the circumferential direction, the arrangement can reasonably run, the iron core at the lower end of the middle of the stator armature tooth and the iron core at the lower end of the stator excitation tooth are main paths of electric excitation magnetic flux, no permanent magnet is arranged at the position, the magnetic resistance is very small, and the electric excitation effect. N and S respectively represent the north pole and south pole of the permanent magnet, Fe represents a stator core, the number of total permanent magnets is 1.4, the number of total permanent magnets is the same as the number of stator teeth, and the number of stator teeth is equal to the sum of 1.2 stator armature teeth and 1.3 stator excitation teeth.

The three-phase armature winding 3 and the single-phase excitation winding 4 are both concentrated windings, the three-phase armature winding 3 is wound on the stator armature teeth 1.2, the single-phase excitation winding 4 is wound on the stator excitation teeth 1.3, the energization directions of the single-phase excitation winding 4 wound on each stator excitation tooth 1.3 are the same, the three-phase armature winding 3 and the single-phase excitation winding 4 occupy the space of a stator slot together in a certain proportion, and the change of the proportion can realize the change of torque performance and magnetic regulation capacity. In simulation, under the condition that the total areas of an alternating current armature winding and a direct current excitation winding are the same, assuming that the alternating current density and the direct current density are fixed and the slot fullness rate is also fixed, the average torque will increase and the magnetic regulation range will decrease as the occupation ratio of the alternating current winding increases, namely the occupation ratio of the direct current winding decreases; as the duty ratio of the ac winding decreases, i.e., the duty ratio of the dc winding increases, the average torque decreases and the field modulation range increases.

The invention discloses an operation principle of a hybrid excitation type flux reversal motor with asymmetric stator poles, which comprises the following steps:

direct currents with different amplitudes and directions are conducted to the single-phase excitation winding to generate electric excitation magnetomotive forces with different sizes and directions, so that an air gap magnetic field is influenced, and the air gap magnetic flux of the motor can be adjusted. When no direct current is led into the single-phase excitation winding 4, namely when only permanent magnet excitation is carried out, the magnetic lines of force are distributed as shown in figure 2, permanent magnets 1.4 on the left side and the right side of the lower end of a stator armature tooth 1.2 generate permanent magnet magnetic flux, and when a rotor tooth 2.1 is close to the permanent magnets 1.4, except for partial permanent magnet magnetic flux leakage, the magnetic flux direction in the stator armature tooth 1.2 is outward in the radial direction; when the rotor teeth are close to the stator core between the two permanent magnets 1.4, the permanent magnetic flux almost completely leaks, the stator armature teeth 1.2 almost have no magnetic flux, taking the stator armature teeth 1.2 at the top as an example, a sinusoidal magnetic flux linkage with forward direct current bias is generated in the three-phase armature windings 3 wound on the stator armature teeth 1.2 along with the rotation of the rotor, at the moment, sinusoidal magnetic flux linkages with reverse direct current bias and the same amplitude and phase are generated in the three-phase armature windings 3 wound on the stator armature teeth 1.2 at the bottom of the same phase, and the two sinusoidal magnetic flux linkages are added to obtain the total alternating sinusoidal magnetic flux linkage of the same phase. When a forward direct current is introduced into the single-phase excitation winding 4, the magnetic lines of force are distributed as shown in fig. 3, when the rotor tooth 2.1 is close to the permanent magnet 1.4, the permanent magnet 1.4 generates permanent magnetic flux, except for partial permanent magnetic flux leakage, the permanent magnetic flux enters the stator armature tooth 1.2, the direction of the magnetic flux is outward in the radial direction, the electromagnetic flux generated by the single-phase excitation winding 4 wound on the stator excitation teeth 1.3 at two sides of the stator armature tooth 1.2 has almost no passage in the stator armature tooth, the electromagnetic flux can be ignored, and therefore, the total direction of the magnetic flux in the stator armature tooth 1.2 is outward in the radial direction; when the rotor teeth are close to the stator core between the two permanent magnets 1.4, the permanent magnetic flux almost completely leaks away, the electromagnetic flux generated by the single-phase excitation winding 4 wound on the stator excitation teeth 1.3 at the two sides of the stator armature teeth 1.2 enters the stator armature teeth 1.2, the electromagnetic flux direction is inward in the radial direction, so the total magnetic flux direction in the stator armature teeth 1.2 is inward in the radial direction, the subsequent analysis is the same as the previous analysis, and finally, an alternating sinusoidal magnetic chain of one phase is obtained, and the amplitude of the alternating sinusoidal magnetic chain is larger than that when no direct current is introduced into the single-phase excitation winding 4. When a reverse direct current is introduced into the single-phase excitation winding 4, the magnetic force lines of the direct current are distributed as shown in fig. 4, when the rotor tooth 2.1 is close to the permanent magnet 1.4, the permanent magnet 1.4 generates permanent magnetic flux, except for partial permanent magnetic flux leakage, the permanent magnetic flux enters the stator armature tooth 1.2, the magnetic flux direction is outward in the radial direction, the electromagnetic flux generated by the single-phase excitation winding 4 wound on the stator excitation teeth 1.3 at two sides of the stator armature tooth 1.2 hardly has a passage in the stator armature tooth, the electromagnetic flux is negligible, and therefore the total magnetic flux direction in the stator armature tooth 1.2 is outward in the radial direction; when the rotor teeth are close to the stator core between the two permanent magnets 1.4, almost all the permanent magnetic flux leaks, the electromagnetic flux generated by the single-phase excitation winding 4 wound on the stator excitation teeth 1.3 at the two sides of the stator armature teeth 1.2 enters the stator armature teeth 1.2, the electromagnetic flux direction is outward in the radial direction, so the total magnetic flux direction in the stator armature teeth 1.2 is outward in the radial direction, the subsequent analysis is the same as the previous analysis, and finally, an alternating sinusoidal magnetic chain of one phase is obtained, and the amplitude of the alternating sinusoidal magnetic chain is smaller than that of the alternating sinusoidal magnetic chain of one phase when no direct current is introduced into the single-phase excitation winding 4.

The above is only the scheme of the invention when the number of rotor teeth is odd, when the number of rotor teeth is even, the basic operation principle is also applicable, but the direct current bias flux linkages generated in each coil in the same-phase armature winding are not offset but added, but the influence on the sine flux linkage part playing a decisive role is smaller.

Because the magnetic circuit of the permanent magnetic flux and the main magnetic circuit of the electric excitation magnetic flux are connected in parallel, on one hand, the electric excitation effect is enhanced, the electric excitation loss is reduced, the magnetic flux adjusting capacity is increased, the rotating speed adjusting range is expanded, and on the other hand, the possibility of permanent magnetic demagnetization generated when the permanent magnetic excitation direction is opposite to the electric excitation magnetic flux direction is reduced.