CN106451976A - E-shaped-iron-core-included mixed excitation flux-switching motor - Google Patents

Abstract

The invention relates to an E-type iron core hybrid excitation flux switching motor, which includes a stator and a rotor with a salient pole structure, wherein the stator includes an even number of E-type iron core units arranged in sequence along the circumferential direction, located adjacent The permanent magnets between the E-shaped iron core units, the armature coil and the excitation coil are all magnetized tangentially, and the magnetization directions of the two adjacent permanent magnets are opposite, and the adjacent electric coils of the adjacent E-shaped iron core units The pivot tooth and the clamped permanent magnet form a stator pole, and armature coils are wound on each stator pole, and N _s /m armature coils symmetrically distributed with the center of the stator circle are connected in series to form a phase armature winding, where N _s is The number of poles of the stator, where m is the number of motor phases, is characterized in that: each stator pole is also wound with the excitation coil, and the direction of the excitation current applied by the excitation coil on the adjacent stator pole is opposite, and each excitation coil is connected in series to form an excitation coil. winding. After adopting the above structure, the present invention can obtain the maximum permanent magnet flux linkage without additional copper loss, and has a large magnetic adjustment range.

Description

E-type iron core hybrid excitation flux switching motor

technical field

The invention relates to the technical field of motors, in particular to the technical field of an E-type iron core hybrid excitation flux switching motor.

Background technique

The flux-switching permanent magnet motor is a new structure stator permanent magnet doubly salient motor. Its permanent magnet steel and armature windings are located on the stator, while the rotor has neither windings nor permanent magnets. Because of its simple structure, reliable operation, easy heat dissipation, high power density, high efficiency, strong load capacity, and high sinusoidal back EMF, it is considered to replace the traditional rotor permanent magnet motor and has a better application prospects.

E-type flux switching permanent magnet motor is a kind of flux switching permanent magnet motor. Its stator core is made of laminated silicon steel sheets, and the stator core is made of E-shaped silicon steel sheets. As published on July 25, 2008 Such a motor is disclosed in the "Working Principle and Performance Analysis of New Stator Permanent Magnet Fault-Tolerant Motor" proposed by Ji Jinghua on the Chinese Journal of Electrical Engineering (Volume 28, No. 21, Page 96). The stator part of the motor is composed of Composed of E-shaped stator cores and permanent magnets, the permanent magnets are distributed at intervals along the circumferential direction, and each permanent magnet is sandwiched between two adjacent E-shaped stator cores, the armature teeth of the adjacent two E-shaped stator cores and all The permanent magnets of the folder are wound with armature windings, and there is no winding on the middle teeth of the E-type stator core. The E-type flux switching permanent magnet motor not only saves permanent magnet materials, but also has fault-tolerant operation capability due to the existence of intermediate teeth.

However, the above-mentioned E-type magnetic flux switching permanent magnet motor has limited magnetic adjustment capability because only permanent magnets are excited. For this reason, people have designed a hybrid excitation flux switching motor with two magnetic potential sources (that is, with permanent magnets and field windings), such as "Magnetics Volume of the Institute of Electrical and Electronics Engineers" published on October 10, 2009 (IEEE TRANSACTIONS ONMAGNETICS), Volume 45, No. 10, pages 4728 to 4731, "A Novel Hybrid Excitation Flux Switching Motor for Hybrid Vehicles" proposed by Professor Hua Wei. And as another example, published on May 4, 2011, "IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY", Volume 60, Issue 4, pages 1365 to 1373 disclosed by Chen Jintao (J.T. Cheng) proposed "A New Type of Hybrid Excitation Flux Switching Motor for Electric/Hybrid Electric Vehicles", both of which have added field windings, and by changing the current of the field windings, both can obtain field-increasing or field-weakening modulation Capability, so it can better overcome the defects of simple E-type flux switching permanent magnet motor. However, the addition of the former excitation winding sacrifices the space of the permanent magnet, which inevitably reduces the air gap flux density, and the power density and torque will also decrease. If it is necessary to increase the flux linkage (magnetization), it is necessary to Magnetizing current is applied in the winding, but this will add additional copper loss. The motor designed by the latter includes a stator 1' and a rotor 2' with a salient pole structure, and the stator includes a plurality of E-shaped iron core units 11' arranged in sequence along the circumferential direction, and the adjacent E-shaped iron core units Between the permanent magnet 12' and the armature coil 13' and the field coil 14', as shown in FIG. 1 . Since the field coil 14' is wound on the middle fault-tolerant teeth of the E-type iron core unit 11' of the E-type magnetic flux switching permanent magnet motor, when the field is increased (excitation current is greater than 0), that is, a positive current is passed into the field winding. Excitation current, the above structure will aggravate the saturation of the stator core and increase the reluctance of the iron core, resulting in a small range of magnetization (see Figure 18 in his paper), and it is even possible that the magnetic field does not increase, but decreases, such as Magnetic modulation effect shown by dotted line in accompanying drawing 4 of this specification. That is to say, when the motor is expected to be magnetized, the flux linkage can become larger, but this ability is very poor, and it is even completely opposite to the result of the desired magnetization, that is, the flux linkage may become smaller. However, this motor will also cause partial saturation of the stator core when the field is weakened, which will increase the reluctance of the iron core, resulting in a small adjustment range for its field weakening. Therefore, the existing E-type iron core hybrid excitation flux switching circuit still needs further improvement.

Contents of the invention

The technical problem to be solved by the present invention is to provide an E-type iron-core hybrid excitation flux switching motor that can obtain the largest permanent magnet flux linkage without additional copper loss and has a large field modulation range.

The technical solution adopted by the present invention to solve the above technical problems is: an E-type iron core hybrid excitation flux switching motor, including a stator and a rotor with a salient pole structure, wherein the stator includes an even number of poles arranged in turn along the circumferential direction The E-shaped iron core unit, the permanent magnet between the adjacent E-shaped iron core units, the armature coil and the excitation coil, the permanent magnets are all tangentially magnetized, and the magnetization direction of the two adjacent permanent magnets On the contrary, the adjacent armature teeth and the clamped permanent magnets of the adjacent E-shaped iron core units form a stator pole, and the armature coils are wound on each stator pole, and the N _s /m electric coils distributed symmetrically with the center of the stator circle The armature coils are connected in series to form a phase armature winding, wherein N _s is the number of poles of the stator, m is the number of motor phases, and it is characterized in that: each stator pole is also wound with the described excitation coil, and the adjacent stator pole The direction of the excitation current applied by the excitation coils on the top is opposite, and each excitation coil is connected in series to form an excitation winding.

In the above scheme, it is preferable that both the excitation winding and the armature winding adopt concentrated windings to reduce copper loss at the ends.

In the above solutions, the rotor can be designed with straight poles. If the relationship between the cogging torque and harmonics of the motor is considered, the rotor needs to adopt oblique poles.

Compared with the prior art, since the excitation coils of the present invention are wound on the salient poles of the stator, and the direction of the excitation current applied by the excitation coils on the adjacent stator poles is opposite, all the excitation coils are connected in series to form an excitation winding, so in the field adjustment , when the excitation winding is fed with current, the excitation current will form a bias magnetic field at the corresponding salient pole of the stator, and the bias magnetic field will make the flux linkage of the symmetrical armature coil in each phase shift upward and downward respectively , that is, the bias magnetic field increases the magnetic density in the stator core where the armature coil is located (that is, the positive increase is upward, and the negative increase is downward, in short, the magnetic density becomes larger), and when the amplitude of the excitation current increases When it is large, the above-mentioned bias magnetic field is also larger. It is the existence of the bias magnetic field that makes the stator core where the armature coil is located gradually saturated, and the change rate of the flux linkage in the armature coil with time becomes smaller, so that the synthesized The phase flux linkage will decrease with the increase of the excitation current amplitude, that is, to achieve the function of field weakening; when the excitation current is zero, the maximum flux linkage can be obtained. That is, the present invention skillfully utilizes the gradual saturation of the stator iron core to make it easy to adjust the magnetic field (magnetic field weakening). Therefore, the present invention can obviously improve the magnetic modulation performance of the motor, so as to meet the speed regulation requirement of the motor.

Description of drawings

Fig. 1 is the structural representation of the motor that Chen Jintao designs in the prior art;

Fig. 2 is the structural representation of the embodiment of the present invention;

Fig. 3 is a diagram showing the variation of phase A flux linkage with excitation current in the embodiment of the present invention, wherein,

Figure 3a is a diagram of the flux linkage change of phase A when the excitation current is 0A;

Figure 3b is a diagram of the flux linkage change of phase A when the excitation current is 10A;

Figure 3c is a diagram of the flux linkage change of phase A when the excitation current is 30A;

Fig. 4 is the contrast diagram of the magnetic adjustment of the motor designed by Chen Jintao in the embodiment of the present invention and the prior art (the A-phase flux linkage amplitude changes with the excitation current);

Fig. 5 is a graph showing the flux linkage of phase A of the motor designed by Chen Jintao in the prior art as it varies with the excitation current, wherein,

Figure 5a is a diagram of the A-phase flux linkage change when the excitation current is 0A;

Figure 5b is a diagram of the A-phase flux linkage change when the excitation current is 10A;

Figure 5c is a diagram of the A-phase flux linkage change when the excitation current is 30A;

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 2, the E-type iron core hybrid excitation flux switching motor includes a stator 1 with N _s poles and a rotor 2 with N _r poles, and the poles of the stator 1 and rotor 2 are designed to be double-convex Pole structure, wherein the stator 1 includes an even number of E-shaped iron core units 11 arranged in sequence along the circumferential direction and permanent magnets 12 between adjacent E-shaped iron core units. In this embodiment, a three-phase 6/13-pole motor As an example (of course also applicable to single-phase motors or motors with more than three phases), that is, the stator has N _s =6 salient poles, and the rotor has N _r =13 salient poles. The six salient poles of the stator are A1 pole, B1 pole, C1 pole, A2 pole, B2 pole, and C2 pole. Six E-shaped iron core units are selected, and each E-shaped iron core unit 11 is made of multiple E-shaped silicon steel The number of permanent magnets 12 is also selected as six, and each permanent magnet 12 is magnetized tangentially, and the magnetization directions of two adjacent permanent magnets are opposite. Adjacent armature teeth of adjacent E-shaped iron core units 11 and clamped permanent magnets 12 form a stator pole, and armature coils 13 and excitation coils 14 are wound on each stator pole, and the excitation coils on adjacent stator poles The direction of the applied field current is opposite. N _s /m armature coils distributed symmetrically with the center of the stator circle are connected in series to form a phase armature winding, where m is the number of motor phases, since in this embodiment, N _s =6, m=3, the above six motors Two symmetrical armature coils in the armature coil 13 are connected in series to form a phase armature winding, that is, the A1 pole armature coil and the A2 pole armature coil in Fig. 1 are connected in series to form the A phase armature winding, and the B1 pole armature coil The coil and the B2-pole armature coil are connected in series to form the B-phase armature winding, and the C1-pole armature coil and the C2-pole armature coil are connected in series to form the C-phase armature winding, that is, the centralized armature winding is adopted; and among the 6 excitation coils They are connected in series to form a centralized excitation winding.

The rotor 2 is located in the space formed by the six E-shaped core units 11 and the six permanent magnets 12. The rotor 2 is made of magnetically permeable material and installed on a rotating shaft made of nonmagnetic material. The rotor is designed to have 13 straight poles, of course it can also be 13 oblique poles, or it can be installed on a rotating shaft made of magnetically permeable material.

The motor in this embodiment can operate as a motor or as a generator.

The motor with the above structure not only retains the advantages of high power density, high efficiency, strong load capacity, and high sinusoidal back EMF of the flux switching permanent magnet motor, but also has fault-tolerant operation capability due to the existence of fault-tolerant teeth. , and also has the advantage of easy processing, especially the motor in the embodiment has better magnetic modulation performance.

Since the change rule of the flux linkage of each phase of the motor is the same, the analysis of the change of the flux linkage of phase A with the excitation current is taken as an example to illustrate that the motor of this embodiment has better magnetic modulation performance.

The flux linkage described below is the no-load flux linkage, that is, the flux linkage provided by the permanent magnet and the field winding when the armature winding does not pass current. As shown in Figure 3, the thin solid line in the figure is the flux linkage change of the A1 pole armature coil during one electrical cycle of the rotor rotation, the dotted line is the flux linkage change of the A2 pole armature coil during one electrical cycle of the rotor rotation, and the thick The solid line is the flux linkage change of phase A after the flux linkage of the armature coil of the A1 pole and the flux linkage of the armature coil of the A2 pole are synthesized during one electric cycle of the rotor rotation. It can be seen from Figure 3a that when the excitation current If is 0A, the variation range of phase A flux linkage is _-0.0652Wb ～﹢ _0.0652Wb ; it can be seen from Figure 3b that when the excitation current If is 10A, The variation range of A-phase flux linkage is about -0.052Wb～﹢0.052Wb; as can be seen from Figure 3c, when the excitation current I _f is 30A, the variation range of A-phase flux linkage is about -0.008Wb～﹢0.008Wb , it can be seen that because the excitation current forms a bias magnetic field, the flux linkages of the A1-pole armature coil and the A2-pole armature coil are shifted upward and downward respectively, and the synthesized A-phase flux linkage increases with the amplitude of the excitation current decrease with increasing value. According to the above variation diagram, the amplitude variation diagram of phase A flux linkage with the excitation current can be drawn, as shown by the solid line in Fig. 4 . It can be seen from the solid line in Figure 4 that when the excitation current I _f increases from 0A to 40A, the amplitude range of the A-phase flux linkage varies from ﹢0.0652Wb to ﹢0.0046Wb, indicating that the A-phase flux linkage increases with the excitation current amplitude The law of increasing and decreasing, and the amplitude range of A-phase flux linkage is relatively large.

However, for the motor designed by Chen Jintao in the prior art, under the same conditions, it can be seen from Figure 5a that when the excitation current is 0A, the variation range of the A-phase flux linkage is about -0.0652Wb～﹢0.0652Wb; It can be seen in 5b that when the excitation current is 10A, the variation range of phase A flux linkage is about -0.0636Wb～﹢0.0636Wb; it can be seen from Figure 5c that when the excitation current is 30A, the flux linkage of phase A The range of variation is about -0.0576Wb～﹢0.0576Wb. It can be seen that the flux linkage of the armature coil of the A1 pole and the flux linkage of the armature coil of the A2 pole are symmetrical subtractions about the X axis (the horizontal line when the flux linkage of the A phase is equal to zero). Small, the synthetic A-phase flux linkage also decreases with the increase of the excitation current amplitude, but the amplitude range is small. From the above change diagram, draw the amplitude variation diagram of phase A flux linkage of the motor designed by Chen Jintao with the excitation current, as shown by the dotted line in Figure 4. It can be seen from the dotted line in Figure 4 that when the excitation current increases from 0A to 40A, the amplitude range of the flux linkage of phase A is ﹢0.065 2Wb～﹢0.054Wb, and the amplitude range of the flux linkage of phase A is small, indicating that its magnetic adjustment ability is limited .

Therefore, it can be seen from FIG. 4 that the magnetic modulation range of the motor in this embodiment is much larger than that of the motor in the prior art.

Claims (3)

1. a kind of E shaped iron core mixed excited magnetic pass switch motor, includes the stator (1) being salient-pole structure and rotor (1), its Middle stator (1) include again E sections core unit (11) that even number is circumferentially arranged in order, be located at adjacent E sections core unit it Between permanent magnet (12) and armature coil (13) and magnet exciting coil (14), described permanent magnet (12) all cutting orientation magnetizings, and phase The magnetizing direction of adjacent two permanent magnets (12) is contrary, the adjacent armatures tooth of adjacent E sections core unit (11) and folded permanent magnet (12) form stator poles, each stator poles are arranged with described armature coil (13), with the symmetrical N in the stator center of circle_s/m A phase armature winding, wherein N is formed after individual armature coil series connection_sFor the number of poles of stator, m be number of motor phases it is characterised in that：Respectively Magnet exciting coil (14) also described in winding in described stator poles, and the excitation electricity that the magnet exciting coil (14) in adjacent stator pole applies Stream is in opposite direction, forms Exciting Windings for Transverse Differential Protection after each magnet exciting coil (14) series connection.

2. E shaped iron core mixed excited magnetic pass switch motor according to claim 1 it is characterised in that：Described Exciting Windings for Transverse Differential Protection With armature winding all using centralized winding.

3. E shaped iron core mixed excited magnetic pass switch motor according to claim 1 and 2 it is characterised in that：Described rotor (2) it is designed to straight pole or oblique pole.