阅读说明：本技术 基于转子磁极调制的有级分区自调磁无级调速系统及方法 (Stepped-region self-regulating magnetic stepless speed regulating system and method based on rotor magnetic pole modulation ) 是由 李健 王凯 刘凡 于 2021-01-28 设计创作，主要内容包括：本发明公开了一种基于转子磁极调制的有级分区自调磁无级调速系统及方法,包括转子磁极调制型混合励磁电机、逆变器、电源、有级无功励磁装置和切换组件；转子磁极调制型混合励磁电机包括定子、励磁绕组、电枢绕组和磁极调制型转子；励磁绕组绕设在定子中,且为交流绕组；电枢绕组通过逆变器与电源相连接；有级无功励磁装置包括并列设置的若干级无功器件,每级无功器件的相数均等于励磁绕组的相数；励磁绕组通过切换组件能与任意一级无功器件相导通。本发明仅需要电枢绕组端的电源和功率变换器。励磁绕组端省去了电源和功率变换器,通过有级无功励磁装置实现了有级分区自调磁。(The invention discloses a stepped region self-regulating magnetic stepless speed regulating system and method based on rotor magnetic pole modulation, comprising a rotor magnetic pole modulation type hybrid excitation motor, an inverter, a power supply, a stepped reactive excitation device and a switching assembly; the rotor magnetic pole modulation type hybrid excitation motor comprises a stator, an excitation winding, an armature winding and a magnetic pole modulation type rotor; the excitation winding is wound in the stator and is an alternating current winding; the armature winding is connected with a power supply through an inverter; the stepped reactive power excitation device comprises a plurality of stages of reactive power devices which are arranged in parallel, and the phase number of each stage of reactive power device is equal to that of the excitation winding; the excitation winding can be conducted with any one stage of reactive device through the switching assembly. The invention requires only a power supply and a power converter at the armature winding end. The excitation winding end omits a power supply and a power converter, and the stepped regional self-regulation of magnetism is realized through a stepped reactive excitation device.)

1. A have grades of district self-regulating magnetism stepless speed control system based on rotor magnetic pole modulation, its characterized in that: the system comprises a rotor magnetic pole modulation type hybrid excitation motor, an inverter, a power supply, a stepped reactive excitation device and a switching assembly;

the rotor magnetic pole modulation type hybrid excitation motor comprises a stator, an excitation winding, an armature winding and a magnetic pole modulation type rotor;

the excitation winding and the armature winding are wound in the stator slot and are both alternating current windings;

the armature winding is connected with a power supply through an inverter;

the stepped reactive power excitation device comprises a plurality of stages of reactive power devices which are arranged in parallel, and the phase number of each stage of reactive power device is equal to that of the excitation winding; the excitation winding can be conducted with any one stage of reactive device through the switching assembly.

2. The stepped-zone self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: the plurality of stages of reactive devices comprise short-circuit stages, open-circuit stages, a plurality of stages of reactors and a plurality of stages of capacitors; the inductances corresponding to the reactors of the plurality of stages are different from each other, and the capacitances corresponding to the capacitors of the plurality of stages are different from each other.

3. The stepped-region self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: the stepped reactive power excitation device comprises five reactive power devices which are arranged in parallel, wherein the five reactive power devices are respectively a first gear, a second gear, a third gear, a fourth gear and a fifth gear, the first gear is a short-circuit gear, the second gear and the third gear are reactors, corresponding inductors are respectively L2 and L3, and L2 is less than L3; the fourth gear is an open circuit stage, and the fifth gear is a capacitor.

4. The stepped-zone self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: the switching component is a switch or a relay.

5. The stepped-zone self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: the magnetic pole modulation type rotor comprises k rotor units which are uniformly distributed along the circumferential direction, and the number of pole pairs of each rotor unit isp ₀(ii) a The number of permanent magnet pole pairs and the number of iron core pole pairs in each rotor unit are respectivelyp _0m Andp _0i (ii) a Then:

p= k×p ₀ (1)

p ₀=2n+1 (2)

p _0m =n (3)

p _0i =n+1 (4)

wherein n and k are positive integers,pthe number of pole pairs of the magnetic pole modulation type rotor.

6. The stepped-region self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: in each rotor unit, 2p _0m The permanent magnetic poles are not connected; 2p _0i Of the core poles, there are two sets of core poles that are in contact.

7. The stepped-region self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation is characterized in that: the number of pole pairs of the armature winding is equal to that of the magnetic pole modulation type rotorpThe number of pole pairs of the field winding being equal tok。

8. A step-area self-regulating magnetic stepless speed regulating method based on rotor magnetic pole modulation is characterized in that: the stepless speed regulation is realized by combining the step-division self-regulation magnetism and the weak magnetism control of the armature winding; the step-by-step area self-regulation of magnetism is realized by conducting an excitation winding and a corresponding reactive device in a step-by-step reactive power excitation device through a switching component, and because the magnetic permeability of an iron core pole is far greater than that of a permanent magnet, the magnetic potential energy of each pole of the excitation winding is simultaneously regulated in a magnetic pole modulation type rotorp _0i Magnetic flux of individual core poles.

9. The stepped-region self-regulating magnetic stepless speed regulating method based on rotor magnetic pole modulation is characterized in that: the specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. a magnetizing mode: when the switching component conducts the excitation winding with any reactor or short-circuit stage in the step reactive power excitation device, the magnetic flux generated by the excitation winding on the iron core pole of the magnetic pole modulation type rotor is opposite to the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the upper direction of the radial direction, and the motor works in a magnetizing mode;

B. permanent magnet individual excitation mode: when the switching assembly conducts the excitation winding with an open-circuit stage in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode;

C. a field weakening mode: when the switching component conducts the exciting winding and the capacitor bank in the step reactive power excitation device, the magnetic flux generated by the exciting winding on the iron core pole of the magnetic pole modulation type rotor is the same as the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the radial direction, so that the motor works in a weak magnetic mode at the moment.

10. The stepped-region self-regulating magnetic stepless speed regulating method based on rotor magnetic pole modulation is characterized in that: the specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. the magnetic increasing mode specifically comprises the following adjusting method:

(1) when the switching component conducts the excitation winding and a first gear in the step reactive power excitation device, the motor works in a magnetizing mode, and the speed range of the motor is V1;

(2) when the switching component conducts the excitation winding with a second gear or a third gear in the step reactive excitation device, the motor works in a magnetizing mode, the speed range of the motor is V2, and V2 comprises V1;

B. permanent magnet individual excitation mode: when the switching component conducts the excitation winding and the four-gear phase in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode; at this time, the speed range of the motor is V3, and V3 includes V2;

C. a field weakening mode: when the switching component conducts the excitation winding with the five-gear phase in the step reactive excitation device, the motor works in a field weakening mode, the rotating speed range of the motor is V4, and then V4 comprises V3.

Technical Field

The invention relates to the field of motor design and manufacture, in particular to a stepped regional self-regulating magnetic stepless speed regulating system and method based on rotor magnetic pole modulation.

Background

Permanent magnet motors have the advantages of high torque/power density, high efficiency, high power factor, etc., and have found use in many applications. However, field weakening of permanent magnet motors is achieved by controlling the direct-axis current component in the armature windingi _d ) To realize that the permanent magnet has wind with irreversible demagnetizationDangerous and has limited weak magnetic capacity.

The hybrid excitation motor has two magnetic potential sources (an excitation winding and a permanent magnet), has the advantage of convenient magnetic field adjustment of the electric excitation motor, and has the advantages of high power density, high efficiency and the like of the permanent magnet motor.

However, in the existing rotor permanent magnet type (permanent magnet is located in the rotor) hybrid excitation motors, direct current excitation is mostly adopted, and the implementation mode of brushless excitation is complex. Moreover, an additional magnetic circuit is introduced while the parallel connection of the permanent magnet and the electric excitation magnetic potential is realized. The permanent magnetic flux is short-circuited through the additional magnetic circuit, and magnetic leakage is formed, so that the utilization rate of the permanent magnetic material is reduced. Furthermore, the additional magnetic circuit is mostly a solid magnetic conductive member, which increases eddy current loss.

In addition, when the existing hybrid excitation motor is used in a speed regulation system, an additional power supply and a power converter are required to supply power to the excitation winding.

Disclosure of Invention

The present invention provides a stepped-region self-regulating magnetic stepless speed regulating system and method based on rotor magnetic pole modulation, which only needs a power supply and a power converter at an armature winding end. The excitation winding end omits a power supply and a power converter, and the stepped regional self-regulation of magnetism is realized through a stepped reactive excitation device.

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

a stepped region self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation comprises a rotor magnetic pole modulation type hybrid excitation motor, an inverter, a power supply, a stepped reactive excitation device and a switching assembly.

The rotor magnetic pole modulation type hybrid excitation motor comprises a stator, an excitation winding, an armature winding and a magnetic pole modulation type rotor.

The excitation winding and the armature winding are wound in the stator slot and are both alternating current windings.

The armature winding is connected to a power source through an inverter.

The step reactive power excitation device comprises a plurality of step reactive devices which are arranged in parallel, and the phase number of each step reactive device is equal to that of the excitation winding. The excitation winding can be conducted with any one stage of reactive device through the switching assembly.

The several stages of reactive devices comprise a short-circuit stage, an open-circuit stage, several stages of reactors and several stages of capacitors. The inductances corresponding to the reactors of the plurality of stages are different from each other, and the capacitances corresponding to the capacitors of the plurality of stages are different from each other.

The stepped reactive power excitation device comprises five-stage reactive power devices which are arranged in parallel, wherein the five-stage reactive power devices are respectively a first gear, a second gear, a third gear, a fourth gear and a fifth gear, the first gear is a short-circuit gear, the second gear and the third gear are reactors, corresponding inductors are respectively L2 and L3, and L2 is less than L3. The fourth gear is an open circuit stage, and the fifth gear is a capacitor.

The switching component is a switch or a relay.

The magnetic pole modulation type rotor comprises k rotor units which are uniformly distributed along the circumferential direction, and the number of pole pairs of each rotor unit isp ₀. The number of permanent magnet pole pairs and the number of iron core pole pairs in each rotor unit are respectivelyp _0m Andp _0i . Then:

p= k×p ₀ (1)

p ₀=2n+1 (2)

p _0m =n (3)

p _0i =n+1 (4)

wherein n and k are positive integers,pthe number of pole pairs of the magnetic pole modulation type rotor.

In each rotor unit, 2p _0m The permanent magnetic poles are not connected. 2p _0i Of the core poles, there are two sets of core poles that are in contact.

The number of pole pairs of the armature winding is equal to that of the magnetic pole modulation type rotorpThe number of pole pairs of the field winding being equal tok。

A step-by-step regional self-regulating magnetic stepless speed regulation method based on rotor magnetic pole modulation is combined with step-by-step regional self-regulating magnetic and weak magnetic control of an armature winding to realize stepless speed regulation. The step-by-step area self-regulation of magnetism is realized by conducting an excitation winding and a corresponding reactive device in a step-by-step reactive power excitation device through a switching component, and because the magnetic permeability of an iron core pole is far greater than that of a permanent magnet, the magnetic potential energy of each pole of the excitation winding is simultaneously regulated in a magnetic pole modulation type rotorp _0i Magnetic flux of individual core poles.

The specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. a magnetizing mode: when the switching component conducts the excitation winding with any reactor or short-circuit stage in the step reactive excitation device, the magnetic flux generated by the excitation winding on the iron core pole of the magnetic pole modulation type rotor is opposite to the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the radial upper direction, and the motor works in a magnetizing mode.

B. Permanent magnet individual excitation mode: when the switching component conducts the excitation winding with an open-circuit stage in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode.

C. A field weakening mode: when the switching component conducts the exciting winding and the capacitor bank in the step reactive power excitation device, the magnetic flux generated by the exciting winding on the iron core pole of the magnetic pole modulation type rotor is the same as the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the radial direction, so that the motor works in a weak magnetic mode at the moment.

The specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. the magnetic increasing mode specifically comprises the following adjusting method:

(1) when the switching component conducts the excitation winding and a first gear in the step reactive power excitation device, the motor works in a magnetizing mode, the torque of the motor in a low-speed area is obviously improved, and the speed range of the motor is V1.

(2) When the switching component conducts the excitation winding with the second gear or the third gear in the step reactive excitation device, the motor works in a magnetizing mode, the speed range of the motor is V2, and V2 comprises V1.

B. Permanent magnet individual excitation mode: when the switching component conducts the excitation winding and the four-gear phase in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode. At this time, the speed range of the motor is V3, and V3 includes V2.

C. A field weakening mode: when the switching component conducts the excitation winding with the five-gear phase in the step reactive excitation device, the motor works in a field weakening mode, the rotating speed range of the motor is V4, and then V4 comprises V3.

The invention has the following beneficial effects:

1. the invention only needs a power supply and a power converter at the armature winding end, saves the power supply and the power converter at the excitation winding end, and realizes the stepped regional self-regulation magnetism through the stepped reactive excitation device.

2. The mixed excitation motor of the speed regulating system is a rotor magnetic pole modulation type mixed excitation motor, and an excitation winding of the mixed excitation motor is an alternating current excitation winding positioned on a stator without an additional magnetic circuit.

3. Because the magnetic conductivity of the iron core pole is far greater than that of the permanent magnet, the magnetic potential of each pole of the alternating current excitation winding can be adjusted simultaneouslyp _0i The magnetic flux of each iron core pole has high magnetic regulation efficiency.

Drawings

Fig. 1 shows a schematic diagram of a stepped-zone self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation.

Fig. 2 shows a circuit topology of the stepped reactive excitation device according to the invention.

Fig. 3 shows the torque-rotation speed curve of the stepped-zone self-regulating magnetic stepless speed regulating system of the invention in different modes.

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.

The invention uses armature winding and AC exciting winding as three phases,p=3（kthe following description will discuss specific examples of = 1).

As shown in fig. 1, a stepped-region self-regulating magnetic stepless speed regulating system based on rotor magnetic pole modulation comprises a rotor magnetic pole modulation type hybrid excitation motor, an inverter (also called power converter), a power supply, a stepped reactive excitation device and a switching assembly.

The rotor magnetic pole modulation type hybrid excitation motor comprises a stator, an excitation winding, an armature winding and a magnetic pole modulation type rotor.

The excitation winding and the armature winding are wound in the stator slot and are both alternating current windings, and the number of phases of the alternating current windings can be three phases, or can be multiple phases such as five phases, double three phases and the like.

The armature winding is connected to a power source through an inverter.

The stepped reactive power excitation device comprises a plurality of stages of reactive devices which are arranged in parallel, and the stages of the reactive devices can be flexibly changed according to different application requirements.

The number of phases of each stage of reactive device is equal to that of the excitation winding. The excitation winding can be conducted with any one stage of reactive device through the switching assembly.

The several stages of reactive devices comprise a short-circuit stage, an open-circuit stage, several stages of reactors and several stages of capacitors. The inductances corresponding to the reactors of the plurality of stages are different from each other, and the capacitances corresponding to the capacitors of the plurality of stages are different from each other.

In the present example, five stages are taken as an example, and as shown in fig. 2, the five stages are numbered as gears in order. Wherein, the first gear is short circuit, that is, the inductance of the reactor is 0. The second gear and the third gear are both reactors, and the inductance L2 of the second gear is smaller than the inductance L3 of the second gear. The fourth gear is open circuit. The fifth gear is a capacitor.

In a preferred embodiment, as shown in fig. 2, the stepped reactive power excitation device includes five parallel reactive power devices, where the five reactive power devices are respectively a first gear, a second gear, a third gear, a fourth gear and a fifth gear, the first gear is a short-circuit gear, the second gear and the third gear are reactors, corresponding inductances are L2 and L3, and L2 is less than L3. The fourth gear is an open circuit stage, and the fifth gear is a capacitor.

Further, the switching member is preferably a switch or a relay.

The magnetic pole modulation type rotor comprises k rotor units which are uniformly distributed along the circumferential direction, and the number of pole pairs of each rotor unit isp ₀. The number of permanent magnet pole pairs and the number of iron core pole pairs in each rotor unit are respectivelyp _0m Andp _0i . Then:

p= k×p ₀ (1)

p ₀=2n+1 (2)

p _0m =n (3)

p _0i =n+1 (4)

wherein n and k are positive integers,pthe number of pole pairs of the magnetic pole modulation type rotor. In the present embodiment, it is preferred that,k=1，n=1.p=3。

in each rotor unit, 2p _0m The permanent magnetic poles are not connected. 2p _0i Of the core poles, there are two sets of core poles that are in contact.

The number of pole pairs of the armature winding is equal to that of the magnetic pole modulation type rotorpThe number of pole pairs of the field winding being equal tok。

As shown in figure 3, a step-area self-regulating magnetic stepless speed regulating method based on rotor magnetic pole modulation combines step-area self-regulating magnetic and armature windingThe group is controlled by weak magnetism to realize stepless (continuous) speed regulation. The step-by-step area self-regulation of magnetism is realized by conducting an excitation winding and a corresponding reactive device in a step-by-step reactive power excitation device through a switching component, and because the magnetic permeability of an iron core pole is far greater than that of a permanent magnet, the magnetic potential energy of each pole of the excitation winding is simultaneously regulated in a magnetic pole modulation type rotorp _0i The magnetic flux of each iron core pole has high magnetic regulation efficiency. Furthermore, stepped zonal self-regulation of the magnetic field is achieved by means of a stepped reactive excitation device (i.e. no additional power supply and power converter is required).

The specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. a magnetizing mode: when the switching component conducts the excitation winding with any reactor or short-circuit stage (note: the AC excitation winding has reactance characteristic) in the step reactive excitation device, the magnetic flux generated by the excitation winding on the iron core pole of the magnetic pole modulation type rotor is opposite to the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the radial upper direction, and the motor works in a magnetizing mode.

B. Permanent magnet individual excitation mode: when the switching component conducts the excitation winding with an open-circuit stage in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode.

C. A field weakening mode: when the switching component conducts the exciting winding and the capacitor bank in the step reactive power excitation device, the magnetic flux generated by the exciting winding on the iron core pole of the magnetic pole modulation type rotor is the same as the magnetic flux generated by the adjacent permanent magnet on the permanent magnet along the radial direction, so that the motor works in a weak magnetic mode at the moment.

The specific magnetic regulating method for the fractional zonal self-regulation comprises the following steps:

A. the magnetic increasing mode specifically comprises the following adjusting method:

(1) when the switching component conducts the excitation winding and a first gear in the step reactive power excitation device, the motor works in a magnetizing mode, the torque of the motor in a low-speed area is obviously improved, the speed range of the motor is V1 and is narrow, and as shown in figure 3, the speed does not exceed 4500 r/min.

(2) When the switching component conducts the excitation winding with the second gear or the third gear in the step reactive excitation device, the motor works in a magnetizing mode, the speed range of the motor is V2, and V2 comprises V1.

B. Permanent magnet individual excitation mode: when the switching component conducts the excitation winding and the four-gear phase in the step reactive power excitation device, the motor works in a permanent magnet independent excitation mode. At this time, the speed range of the motor is V3, and V3 contains V2, i.e. is wider than the speed range during magnetizing, and as shown in FIG. 3, does not exceed 6000 r/min.

C. A field weakening mode: when the switching component conducts the excitation winding with the five-gear phase in the step reactive excitation device, the motor works in a field weakening mode, the rotating speed range of the motor is V4, and V4 contains V3, namely the rotating speed range is the widest at the moment, and as shown in FIG. 3, 8000 r/min can be achieved.

For an electric automobile, when a low speed with good climbing capability is required, the motor is required to output a large torque, and the magnetism increasing mode of the invention can increase the output torque at the low speed. When the electric automobile runs on a highway, good high-speed cruising ability is required, so that a wider running rotating speed range is required, and the invention can widen the running rotating speed range and increase the constant-power cruising ability in a weak magnetic mode.

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.