阅读说明：本技术 裂极型永磁辅助同步磁阻电机 (Split pole type permanent magnet auxiliary synchronous reluctance motor ) 是由 李健 王凯 刘闯 孙海阳 朱姝姝 于 2021-07-12 设计创作，主要内容包括：本发明公开了一种裂极型永磁辅助同步磁阻电机,包括定子、裂极型同步磁阻转子和电枢绕组；电枢绕组极对数与裂极型同步磁阻转子的极对数相等,均为p；裂极型同步磁阻转子的转子极为裂极或裂极与磁阻极的组合,每个裂极均包括永磁部分和磁阻部分；当转子极均为裂极时,裂极的极对数p-(s)=p；当转子极为裂极与磁阻极的组合时,裂极的极对数p-(s)＜p,且裂极的极对数p-(s)与磁阻极的极对数p-(r)之和等于p。本发明具有反凸极特性,能在低速运行时,采用正的i-(d)利用磁阻转矩,避免永磁体发生不可逆退磁；能获得更大的直轴电感,弱磁扩速能力强；能拓宽恒功率调速范围。还能在抑制了偶次谐波的同时,提高有效的相磁链或相反电动势。(The invention discloses a split-pole permanent magnet auxiliary synchronous reluctance motor which comprises a stator, a split-pole synchronous reluctance rotor and an armature winding, wherein the stator is provided with a stator core and a stator core; the number of pole pairs of the armature winding is equal to that of the split pole type synchronous reluctance rotor p (ii) a The rotor pole of the split pole type synchronous reluctance rotor is a split pole or a combination of the split pole and the reluctance pole, and each split pole comprises a permanent magnet part and a reluctance part; when the rotor poles are all split poles, the pole pair number of the split poles p s = p (ii) a When rotor poles are a combination of split poles and reluctance poles, the pole pair number of the split pole p s ＜ p And the number of pole pairs of the split pole p s Pole pair number with reluctance pole p r The sum being equal to p . The invention has the characteristic of reverse salient pole, and can adopt positive pole when running at low speed i d The irreversible demagnetization of the permanent magnet is avoided by utilizing the reluctance torque; larger direct-axis inductance can be obtained, and the weak magnetic speed-expanding capability is strong; the constant power speed regulation range can be widened. And the effective phase flux linkage or the reverse electromotive force can be improved while even harmonics are inhibited.)

1. The utility model provides a synchronous reluctance motor is assisted to split pole type permanent magnetism which characterized in that: the synchronous reluctance motor comprises a stator and a split-pole synchronous reluctance rotor which are coaxially sleeved;

the stator comprises a stator core and an armature winding wound in stator slots of the stator core; the number of pole pairs of the armature winding is equal to that of the split pole type synchronous reluctance rotorp；

The split-pole type synchronous reluctance rotor comprises a rotor core and rotor poles distributed on the rotor core along the circumferential direction;

the rotor pole is a split pole or a combination of the split pole and a magnetic resistance pole, and each split pole comprises a permanent magnet part and a magnetic resistance part;

when the rotor poles are all split poles, the pole pair number of the split polesp _s =p(ii) a The direct-axis magnetic circuit of the split pole is closed through the rotor core, and the magnetic resistance of the direct-axis magnetic circuit of the split pole is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the split pole;

when rotor poles are a combination of split poles and reluctance poles, the pole pair number of the split polep _s ＜pAnd the number of pole pairs of the split polep _s Pole pair number with reluctance polep _r The sum being equal top(ii) a The direct-axis magnetic circuits of the split poles and the reluctance poles are closed through the rotor core, and the reluctance of the direct-axis magnetic circuit of the split poles is smaller than the quadrature axis of the split polesAnd the magnetic circuit reluctance is smaller than the quadrature axis magnetic circuit reluctance of the magnetic resistance pole.

2. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein:p _s the split poles are formed on the circumference of the rotor corep _s A pair of circumferentially connected split poles; the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are opposite in polarity, and the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are connected or separated.

3. The split pole permanent magnet assisted synchronous reluctance machine of claim 2, wherein: in each circumferential phase split pole pair, the permanent magnet part of one split pole is a positive pole permanent magnet part, the permanent magnet part of the other split pole is a negative pole permanent magnet part, and a phase magnetic flux linkage or a reverse electromotive force generated by the positive pole permanent magnet part in an armature winding is complementarily superposed with a phase magnetic flux linkage or a reverse electromotive force generated by the negative pole permanent magnet part, so that the effective phase magnetic flux linkage or the reverse electromotive force can be improved while even-order harmonics are inhibited.

4. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein: the permanent magnet part and the magnetic resistance part in each split pole respectively account for half.

5. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein: when the rotor poles are a combination of split poles and reluctance poles, the split poles and reluctance poles are symmetrically distributed over the entire machine circumference.

6. The split pole permanent magnet assisted synchronous reluctance machine of claim 5, wherein: when the rotor pole is the combination of the split pole and the reluctance pole, for the split pole and the reluctance pole which are connected in the circumference, the straight-axis central line of the reluctance pole and the central line of the split pole have a pole distance difference.

7. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein: the magnetic resistance parts of the magnetic resistance pole and the split pole adopt a magnetic barrier, a salient pole or a mode of combining the salient pole and the magnetic barrier.

8. The split pole permanent magnet assisted synchronous reluctance machine of claim 7, wherein: when the magnetic resistance parts of the magnetic resistance pole and the split pole adopt magnetic barriers, the magnetic barriers are arranged on the quadrature-axis magnetic circuit to increase the magnetic resistance of the quadrature-axis magnetic circuit; when the magnetic resistance parts of the magnetic resistance pole and the split pole adopt salient poles, the straight axis is the central line of the salient pole or the split pole; when the magnetic resistance parts of the magnetic resistance pole and the split pole adopt a mode of combining a salient pole and a magnetic barrier, the magnetic barrier is arranged on a quadrature axis magnetic path, and a direct axis is the central line of the salient pole or the split pole.

9. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein: the permanent magnet part of the split pole is also provided with a quadrature axis magnetic barrier.

10. The split pole permanent magnet assisted synchronous reluctance machine of claim 1, wherein: the permanent magnet part of the split pole has an offset angle relative to the reluctance part of the split pole, and the offset angle is smaller than or equal to 1/4 pole pitch, so that the current angle of the maximum torque obtained by the permanent magnet torque approaches the current angle of the maximum torque obtained by the reluctance torque, and the utilization rate of the permanent magnet torque and the reluctance torque is improved.

Technical Field

The invention relates to the field of motor design and manufacture, in particular to a split pole type permanent magnet auxiliary synchronous reluctance motor.

Background

Permanent magnet motors have the advantages of high torque/power density, high efficiency, high power factor, etc., and have been used in a number of fields. Rotor permanent magnet motors can be classified into surface-mounted permanent magnet motors and interior permanent magnet motors according to the mounting manner of permanent magnets on a rotor. In applications requiring wide-range speed regulation (wide-area) operation, such as electric vehicles, a built-in permanent magnet motor is often used.

Conventional interior permanent magnet machines pass through a positive salient pole (L)_qGreater than L_d) Designed to utilize reluctance torque to improve torque output capability when operating below base speed (low speed region). And they usually employ flux weakening control (i.e. control of the direct current of the armature winding to be negative, -i)_d) To achieve speed-expanding (high-speed zone) operation.

However, the conventional positive salient pole interior permanent magnet motor has the problems of difficulty in considering high power density, wide rotating speed operation range, demagnetization resistance, high reliability and low cost, and the specific expression is as follows:

1) due to L_q＞L_d(the direct-axis magnetic resistance is larger than the quadrature-axis magnetic resistance), when the positive salient pole built-in permanent magnet motor utilizes the magnetic resistance torque in a low-speed region, the negative direct-axis current (i.e. -i) must be adopted_d) The risk of irreversible demagnetization of the permanent magnet increases.

2) If the irreversible demagnetization risk is reduced, the thickness of the permanent magnet must be increased, and then the cost of the permanent magnet material (note: rare earth permanent magnetic materials are non-renewable natural resources and strategic resources).

3) And a direct-axis magnetic circuit of the permanent magnet motor with the built-in positive salient pole passes through the permanent magnet, so that the direct-axis inductance is small (the direct-axis magnetic resistance is large). The increased thickness of the permanent magnet further reduces the direct-axis inductance (note: the weak magnetic capacity is closely related to the direct-axis inductance), thereby reducing the weak magnetic capacity and limiting the speed-expanding operation range.

4) The positive salient pole built-in permanent magnet motor has large no-load back electromotive force, and when a fault occurs during high-speed operation, not only a large short-circuit current (which is easy to damage the motor) is likely to be generated, but also a weak magnetic failure is likely to occur to generate a feedback power generation condition (which is easy to damage a power device in a control system), so that the reliability is reduced.

Disclosure of Invention

The present invention is directed to a split-pole permanent-magnet-assisted synchronous reluctance machine, which has a reverse-salient pole characteristic and can operate at a low speed by using a positive i_dThe irreversible demagnetization of the permanent magnet is avoided by utilizing the reluctance torque; larger direct-axis inductance can be obtained, and the weak magnetic speed-expanding capability is strong; the constant power speed regulation range can be widened.

In order to solve the technical problems, the invention adopts the technical scheme that:

a split-pole permanent magnet auxiliary synchronous reluctance motor comprises a stator and a split-pole synchronous reluctance rotor which are coaxially sleeved.

The stator comprises a stator core and an armature winding wound in stator slots of the stator core; the number of pole pairs of the armature winding is equal to that of the split pole type synchronous reluctance rotor, and is p.

The split-pole synchronous reluctance rotor comprises a rotor core and rotor poles distributed on the rotor core along the circumferential direction.

The rotor poles are split poles or a combination of split poles and reluctance poles, each split pole comprises a permanent magnet part and a reluctance part.

When the rotor poles are all split poles, the pole pair number p of the split poles_sP; the direct-axis magnetic circuit of the split pole is closed through the rotor core, and the magnetic resistance of the direct-axis magnetic circuit of the split pole is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the split pole.

When the rotor pole is a combination of a split pole and a reluctance pole, the pole pair number p of the split pole_s< p, and the number of pole pairs p of the split pole_sPoles with reluctance polesLogarithm of p_rThe sum is equal to p; the direct-axis magnetic circuits of the split poles and the magnetic resistance poles are closed through the rotor iron core, the magnetic resistance of the direct-axis magnetic circuit of the split poles is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the split poles, and meanwhile, the magnetic resistance of the direct-axis magnetic circuit of the magnetic resistance poles is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the magnetic resistance poles.

p_sThe split poles form at least p on the circumference of the rotor core_sA pair of circumferentially connected split poles; the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are opposite in polarity, and the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are connected or separated.

In each circumferential phase split pole pair, the permanent magnet part of one split pole is a positive pole permanent magnet part, the permanent magnet part of the other split pole is a negative pole permanent magnet part, and a phase magnetic flux linkage or a reverse electromotive force generated by the positive pole permanent magnet part in an armature winding is complementarily superposed with a phase magnetic flux linkage or a reverse electromotive force generated by the negative pole permanent magnet part, so that the effective phase magnetic flux linkage or the reverse electromotive force can be improved while even-order harmonics are inhibited.

The permanent magnet part and the magnetic resistance part in each split pole respectively account for half.

When the rotor poles are a combination of split poles and reluctance poles, the split poles and reluctance poles are symmetrically distributed over the entire machine circumference.

When the rotor pole is the combination of the split pole and the reluctance pole, for the split pole and the reluctance pole which are connected in the circumference, the straight-axis central line of the reluctance pole and the central line of the split pole have a pole distance difference.

The magnetic resistance parts of the magnetic resistance pole and the split pole adopt a magnetic barrier, a salient pole or a mode of combining the salient pole and the magnetic barrier.

When the magnetic resistance parts of the magnetic resistance pole and the split pole adopt magnetic barriers, the magnetic barriers are arranged on the quadrature-axis magnetic circuit to increase the magnetic resistance of the quadrature-axis magnetic circuit; when the magnetic resistance parts of the magnetic resistance pole and the split pole adopt salient poles, the straight axis is the central line of the salient pole or the split pole; when the magnetic resistance parts of the magnetic resistance pole and the split pole adopt a mode of combining a salient pole and a magnetic barrier, the magnetic barrier is arranged on a quadrature axis magnetic path, and a direct axis is the central line of the salient pole or the split pole.

The permanent magnet part of the split pole is also provided with a quadrature axis magnetic barrier.

The permanent magnet part of the split pole has an offset angle relative to the reluctance part of the split pole, and the offset angle is smaller than or equal to 1/4 pole pitch, so that the current angle of the maximum torque obtained by the permanent magnet torque approaches the current angle of the maximum torque obtained by the reluctance torque, and the utilization rate of the permanent magnet torque and the reluctance torque is improved.

The invention has the following beneficial effects:

1. the invention has the characteristic of reverse salient pole (namely L)_q＜L_d). When operating below the base speed (low speed region), positive i is used_dReluctance torque is utilized. Positive i_dIn order to increase the magnetic current, the irreversible demagnetization of the permanent magnet is avoided.

2. Because the straight-axis magnetic circuits of the split pole and the magnetic resistance pole are closed through the iron core, the invention can obtain larger straight-axis inductance and stronger weak magnetic speed expansion capability.

3. The current angle regulation range of the invention is wide (i) in the full-speed operation range_dAnd the constant power speed regulation range can be widened by the invention.

4. The no-load back electromotive force of the invention is low, and the invention has stronger short-circuit current inhibition capability and higher reliability.

5. The permanent magnet part of the split pole can be designed in an offset manner, so that the current angle of the maximum permanent magnet torque approaches the current angle of the maximum reluctance torque (called moment angle approach for short), thereby improving the synthesis rate of the permanent magnet torque and the reluctance torque and improving the output torque.

6. The distribution of the split poles of the invention meets the 'magnetic circuit complementary condition', thereby realizing the complementary superposition of the phase magnetic flux linkage (or the opposite electromotive force) generated by the permanent magnet part of the positive pole in the armature winding and the phase magnetic flux linkage (or the opposite electromotive force) generated by the permanent magnet part of the negative pole, namely improving the effective phase magnetic flux linkage (or the opposite electromotive force) while inhibiting even harmonics.

Drawings

Fig. 1 is a schematic structural diagram of a split-pole permanent magnet assisted synchronous reluctance motor in embodiment 1 of the present invention.

Fig. 2 is a schematic structural view of a split type synchronous reluctance rotor in embodiment 1 of the present invention.

Fig. 3 is a schematic structural diagram of a single split pole in embodiment 1 of the present invention.

Fig. 4 is a graph of the counter electromotive force generated by the positive/negative permanent magnet parts alone according to the rotor position in example 1.

Fig. 5 is a graph of the counter electromotive force generated by the positive and negative permanent magnet portions in accordance with the position of the rotor in example 1.

FIG. 6 is a comparative analysis chart of the order of the counter electromotive force generated by the positive electrode, the negative electrode and the two parts in example 1.

Fig. 7 is a schematic diagram of the position shift of the permanent magnet part of the split pole in embodiment 2.

Fig. 8 is a schematic structural diagram of a split-pole permanent magnet assisted synchronous reluctance motor according to embodiment 3 of the present invention.

Fig. 9 is a schematic structural diagram of a split-pole permanent magnet assisted synchronous reluctance motor according to embodiment 4 of the present invention.

Among them are:

10. a stator core; 11. an armature winding;

20. a rotor core; 21. a magnetoresistive electrode; 22. splitting the anode; 23. a magnetoresistive portion; 24. a permanent magnet portion; 25. crossed-axis magnetic barriers; 26. a permanent magnet; 27. the permanent magnet part is offset from the gap; 28. the bridge is mechanically connected.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

In the description of the present invention, it is to be understood that the terms "left side", "right side", "upper part", "lower part", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and that "first", "second", etc., do not represent an important degree of the component parts, and thus are not to be construed as limiting the present invention. The specific dimensions used in the present example are only for illustrating the technical solution and do not limit the scope of protection of the present invention.

Example 1 inner rotor, three phases m-3, Ns-24，p＝4，p_s＝2，p_r2 for example

As shown in fig. 1, a split-pole permanent magnet assisted synchronous reluctance motor includes a stator and a split-pole synchronous reluctance rotor coaxially sleeved together. The split pole type synchronous reluctance rotor can be an inner rotor or an outer rotor.

The stator comprises a stator core 10 and armature windings 11 wound in stator slots of the stator core. In embodiment 1, the number of stator slots is preferably Ns 24, the armature winding is a three-phase winding including A, B, C three-phase windings, where the a phase may be formed by connecting coils a1, a2, A3, and a4 in series, or may be connected in parallel after being connected in series by a1-a2, A3-a4, respectively; and the phases B and C are analogized in the same way.

The number of pole pairs of the armature winding is equal to that of the split synchronous reluctance rotor, and p is preferably 4.

As shown in fig. 2, the split-pole type synchronous reluctance rotor includes a rotor core 20 and rotor poles circumferentially arranged on the rotor core.

The stator core and the rotor core are made of magnetic materials.

As shown in fig. 3, each of the split poles includes a permanent magnet portion 24 and a reluctance portion 23. In the embodiment 1, each split pole is composed of a half permanent magnet pole (permanent magnet part) and a half reluctance pole (reluctance part), and may be slightly larger or slightly smaller than half as an alternative. In embodiment 1, the permanent magnet 26 of the permanent magnet portion is a surface-mount permanent magnet.

The rotor pole is a split pole 22 or a combination of a split pole and a reluctance pole 21.

A. When the rotor poles are all split poles, the pole pair number p of the split poles_sP; the direct-axis magnetic circuit of the split pole is closed through the rotor core, and the magnetic resistance of the direct-axis magnetic circuit of the split pole is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the split pole.

B. When the rotor pole is a combination of a split pole and a reluctance pole, the pole pair number p of the split pole_s< p, and the number of pole pairs p of the split pole_sNumber of pole pairs p with reluctance poles_rThe sum is equal to p.

In this example 1, the number of pole pairs p of the split pole_s2 pole pair number p of magneto-resistive pole_r2. Alternatively, the treatment can be performed according to different requirementsThe pole pairs of the split pole and the magnetic resistance pole can be flexibly selected according to occasions and requirements.

In order to avoid introducing unbalanced magnetic pull force, the split poles and the reluctance poles are symmetrically distributed on the whole mechanical circumference.

For the circumferentially connected split pole and reluctance pole, the straight axis center line of the reluctance pole preferably has a pole distance with the center line of the split pole, but can be slightly larger or smaller than the pole distance so as to meet the special design requirements of torque ripple suppression, moment angle approximation and the like.

The magnetic resistance part of the magnetic resistance pole and the magnetic resistance part of the split pole can adopt a magnetic barrier, a salient pole or a mode of combining the salient pole and the magnetic barrier.

A. When the magnetic resistance parts of the magnetic resistance pole and the split pole adopt magnetic barriers, the magnetic barriers are arranged on the quadrature-axis magnetic circuit, and the magnetic resistance of the quadrature-axis magnetic circuit is increased. In this manner, in the present embodiment 1, the magnetic barriers provided on the quadrature magnetic circuit are also referred to as quadrature magnetic barriers 25. The magnetic barriers of each magnetic resistance pole can be distributed symmetrically or asymmetrically. And the two sides of each quadrature axis magnetic barrier are provided with mechanical connecting bridges 28.

B. When the magnetic resistance parts of the magnetic resistance pole and the split pole adopt salient poles, the direct axis is the central line of the salient pole or the split pole, and the magnetic resistance of the quadrature-axis magnetic circuit is increased when the quadrature-axis magnetic circuit passes through the thicker air gap area of the non-uniform air gap.

C. When the magnetic resistance parts of the magnetic resistance pole and the split pole adopt a mode of combining a salient pole and a magnetic barrier, the magnetic barrier is arranged on a quadrature axis magnetic path, and a direct axis is the central line of the salient pole or the split pole.

The direct-axis magnetic circuits of the split poles and the magnetic resistance poles are closed through the rotor iron core, the magnetic resistance of the direct-axis magnetic circuit of the split poles is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the split poles, and meanwhile, the magnetic resistance of the direct-axis magnetic circuit of the magnetic resistance poles is smaller than the magnetic resistance of the quadrature-axis magnetic circuit of the magnetic resistance poles. At this time, the quadrature inductance L_q< direct axis inductance L_dTherefore, the present invention can obtain the anti-salient pole characteristic. Using positive i_dA positive reluctance torque can be obtained; i.e. the invention can pass through positive i_dReluctance torque is utilized.

In example 1, the distribution of the split poles satisfies the "magnetic path complementary condition", specifically:

p_sthe split poles form at least p on the circumference of the rotor core_sA pair of circumferentially connected split poles; the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are opposite in polarity, and the permanent magnet parts of the two split poles in each circumferentially connected split pole pair are connected or separated. The permanent magnet parts of the two phase-split poles are separated, are not simply separated, and are in a 'permanent magnet part-magnetic resistance part-permanent magnet part' separation mode.

In each circumferentially connected split pole pair, the permanent magnet part of one split pole is a positive permanent magnet part, the permanent magnet part of the other split pole is a negative permanent magnet part, and the phase magnetic flux linkage (or the opposite electromotive force) generated by the positive permanent magnet part in the armature winding is complementarily superposed with the phase magnetic flux linkage (or the opposite electromotive force) generated by the negative permanent magnet part, i.e. the effective phase magnetic flux linkage (or the opposite electromotive force) is improved while even-order harmonics are inhibited. As shown in fig. 4-6. The counter electromotive force under the independent work of the positive permanent magnet part and the counter electromotive force under the independent work of the negative permanent magnet part both have even harmonic waves (such as 2 times, 4 times and the like), and the amplitude of the fundamental wave (effective component) is lower; even harmonics of opposite potentials under the combined action of the positive and negative permanent magnets are eliminated, and fundamental waves are effectively improved.

Example 2: permanent magnet partial offset of split pole

As shown in fig. 7, the permanent magnet part of the split pole is angularly offset from the reluctance part (example 2, the offset angle is 1/8 of the pole pitch, and generally the offset angle is less than or equal to 1/4 of the pole pitch), so that the current angle at which the permanent magnet torque reaches the maximum value approaches the current angle at which the reluctance torque reaches the maximum value (referred to as "moment angle approach"), thereby increasing the synthesis rate of the permanent magnet torque and the reluctance torque and increasing the output torque.

The position corresponding to the offset angle, that is, the position where the permanent magnet part is offset from the gap 27, can be filled with a magnetic barrier or a non-magnetic conductive material.

Example 3: p is 3, using p_s＝2，p_r＝1

As shown in fig. 8, p is 3 in this example_s＝2，p_r1. The permanent-magnet part of the split pole is provided with a crossed-axis magnetic barrier, so that the permanent-magnet partThe magnetic resistance of the direct-axis magnetic circuit is smaller than that of the quadrature-axis magnetic circuit, so that the anti-salient pole characteristic of the motor is further enhanced.

Example 4: p is 3, using p_s＝2，p_r＝1

As shown in fig. 9, the permanent magnet part of the split pole of the present example employs a built-in V-shaped permanent magnet. Alternatively, the permanent magnet may be a linear type, a V type, a C type, a W type, a U type, or the like, or may be a multi-layer hybrid type.

Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the details of the embodiments, and various equivalent modifications can be made within the technical spirit of the present invention, and the scope of the present invention is also within the scope of the present invention.