CN106655547A - New energy automobile motor - Google Patents

Abstract

The invention discloses a new energy automobile motor, which comprises a motor stator and a rotor, wherein the motor stator adopts a fractional slot concentrated winding mode, and the rotor adopts a singular shape and an inverted eight-shaped magnetic steel. The invention belongs to a type of driving motor of a new energy vehicle. The structure of near-pole slots effectively avoids electromagnetic unbalance, and at the same time has the advantages of low cogging torque and low harmonics of fractional slot concentrated windings. The stator adopts the fractional slot concentrated winding mode. Compared with the distributed winding, it basically has no ends and the installation space is small; the fractional slot winding greatly reduces the harmonic content. The rotor adopts an inverted figure-eight magnet, which has a higher air gap magnetic density than surface-mounted magnets. Compared with the existing new energy vehicle driving motor technology, the present invention has small installation space, high power density, high torque density, small cogging torque and low harmonics.

Description

A new energy vehicle motor

technical field

The invention relates to the field of new energy vehicles, in particular to a driving motor applied to new energy vehicles.

Background technique

Automobiles are an important part of modern society and one of the great achievements of industrial development. It is not only the backbone of the world's economy, but also makes a huge contribution to the rapid movement of people's daily life. However, internal combustion engine vehicles that use carbon resources as kinetic energy not only emit carbon dioxide and other pollutants, causing global climate warming, but also small particles in the emissions are also an important culprit of smog. According to statistics from the Chinese Academy of Sciences, about 22.2% of PM2.5 comes from vehicle exhaust. In addition, the earth's oil resources are rapidly decreasing, and the study of alternative energy sources is also the focus of current researchers and industry.

In the past ten years, new energy vehicles, including pure electric vehicles and hybrid vehicles, have emerged as the times require, using high-performance drive motors and their control technology and efficient integration of energy storage systems to replace internal combustion engines and their mechanical transmission systems in traditional vehicles , has become a milestone development node in the field of transportation research and development.

Electric motors and their drive systems are the heart of electric vehicles. The system is mainly composed of automotive motors, power converters and controllers. Among them, the automobile motor directly converts electrical energy into mechanical energy to directly drive the vehicle; the power converter provides the excitation voltage and current of specific indicators according to the indicators of the motor; the controller provides signal control through the converter according to the vehicle condition, road condition and driver's intention The output of the power converter, which in turn adjusts the operation of the car's electric motor to produce a specific torque and speed.

The automotive motor is the core of the entire electric vehicle drive system, and its performance is not only related to the driving comfort of the vehicle, but also determines the battery life of the electric vehicle. At first, electric vehicles used DC motor systems. With the continuous development of motor design and production technology, asynchronous motors, permanent magnet motors and switched reluctance motors have gradually developed into automotive motors. So far, the US market is mainly electric vehicles driven by asynchronous motors. Tesla is its representative. The efficiency of the asynchronous vehicle drive motor used in its high-performance pure electric vehicle T3 is 92%; The lack of research mainly focuses on switched reluctance motors; the Asian market is mainly permanent magnet motors, among which Toyota is famous for its Prius motor in the field of electric vehicles, and its embedded permanent magnet synchronous vehicle drive motor and hybrid synchronous drive system are in the Oak Ridge National The comprehensive efficiency test result of the laboratory is 77%.

Therefore, permanent magnet motors are welcomed by the new energy vehicle industry for their high efficiency and high power density. However, the efficiency of permanent magnet motors for new energy vehicles still needs to be improved; in addition, automotive motors operate in a sealed environment, and the performance of permanent magnet motors is greatly affected by temperature. Research on cooling methods is also a hot spot in the research of new energy vehicle motors one.

Contents of the invention

Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a motor for new energy vehicles with small cogging torque, low harmonic content and high power density, so as to improve the efficiency and stability of the operation of new energy vehicles; On the basis of the existing technology, the battery life of the car can be effectively enhanced.

Technical solutions:

A motor for new energy vehicles, which adopts the form of an outer stator and an inner rotor. The stator is formed by coupling a plurality of single-tooth stator cores, and the stator teeth in each single-tooth stator core are provided with armature windings in the form of full-tooth windings. After coupling, the fractional slot centralized winding is formed as a whole; the rotor includes a rotor core and magnetic poles, and the rotor core includes a main part of the rotor core and a supplementary part of the rotor core; it is a singular shape, and passes through the core corresponding to each magnetic pole along a certain arc It is made after cutting; the main part of the rotor core includes the base body and the teeth arranged on the base body, and the whole is in the shape of a gear, and a rotor core supplementary part is arranged between two adjacent teeth, and the rotor core supplementary part and the base body There is an air-cooling channel, and each magnetic pole is a magnet, which is equally divided into two magnetic steels and installed between the two sides of the supplementary part of the same rotor core and the teeth at the corresponding positions, so that each magnetic pole forms a figure-eight structure, of which The eight-shaped small end opening points to the center of the rotor, and the polarities of two adjacent magnetic poles are opposite to form an interval between the N pole and the S pole.

Further, in the present invention, the motor adopts a motor structure with close pole slots and the least common multiple of the number of pole slots is less than or equal to 12. In the present invention, a structure of 12 slots and 8 poles is specifically adopted, and there are 12 single-tooth stator cores and 8 magnetic poles of the rotor core. In the case that there are 12 single-tooth stator cores, each single-tooth stator core represents an arc of 30 degrees.

Further, in the present invention, the stator adopts a modular design, and on the two side walls of each single-tooth stator core used to connect with the adjacent single-tooth stator cores on both sides, one side is a groove, The other side is a convex groove matching the groove, and the adjacent single-tooth stator core forms a complete stator structure through the combination of the groove and the convex groove. The full-tooth winding cannot exceed the range of the single-tooth stator core to avoid coupling between the single-tooth stator cores.

Further, in the present invention, the size of the rotor is determined after the optimization condition of the minimum cogging torque, and the specific process is: determine the initial stator thickness, stator split ratio, the thickness of each magnetic steel and the supplementary part of the rotor further adjust the above initial parameters according to the precision of the processing technology; then use the simulation software to perform simulation calculations, and finally take the minimum cogging torque as the optimization goal. Under the simulation results of the minimum cogging torque, the corresponding stator and rotor size for the final plan.

Further, in the present invention, the size of the magnetic steel is determined after optimizing the condition that the average air gap magnetic field density of the motor is the largest and the harmonics are the smallest in a steady state.

Further, in the present invention, the air-cooling channel is located between two magnetic steels in a figure-eight structure, and is closer to the center of the rotor than the magnetic steels in the axial direction; the height of the air-cooling channel is not less than the thickness of each magnetic steel , the magnetic isolation effect is obvious; the width of the air-cooling channel is smaller than the width of a single magnetic pole, preferably the width of the air-cooling channel is 1/2 of the width of a single magnetic pole.

Among the above dimensions, the height dimension of the air-cooling channel is defined as follows: on the section perpendicular to the axial direction of the motor, the dimension distributed along the radial direction. The thickness dimension of the air-cooling channel is defined as follows: the dimension perpendicular to the height direction of the air-cooling channel. The thickness dimension of the magnetic steel is defined as follows: on the section perpendicular to the axial direction of the motor, the dimension distributed along the radial direction is the width of the magnetic steel, and the dimension perpendicular to the width direction of the magnetic steel is the thickness of the magnetic steel. The width dimension of a single magnetic pole is defined as follows: on the section perpendicular to the axial direction of the motor, the dimension distributed along the radial direction.

Beneficial effect:

The invention belongs to a new energy automobile motor, which has the advantages of small end, small positioning force, low harmonic content, high power density, high torque density and the like. In the present invention, the motor of the new energy vehicle fully utilizes the characteristics of the inner rotor of the outer stator with 12 slots and 8 poles. The use of distributed concentrated winding structure effectively reduces the size of the end of the motor, simplifies the production process of the motor, reduces the installation space of the motor, and provides the comfort of the car; in addition, the significant reduction in the length of the end effectively reduces the Copper consumption reduces copper consumption, thereby increasing efficiency; adopting a modular stator structure and a full-tooth winding winding form is conducive to the mechanized production of the motor and improves production efficiency, and the modular structure increases the efficiency. The maintainability of the motor; the use of eight-shaped magnetic steel greatly increases the magnetic field density of the air gap, thereby increasing the power density and torque density of the motor; the use of rotor air cooling channels effectively reduces the internal temperature of the motor and avoids The magnetic field of the eight-shaped magnetic field is short-circuited; the unique rotor structure is adopted to effectively reduce the harmonics of the motor, and further improve the effective power density and safety and stability of the motor.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is a schematic structural view of the stator of the present invention.

detailed description

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

As shown in Figure 1, the new energy automobile motor of the present invention adopts the form of an outer stator and an inner rotor, and there is an air breath 5 between the stator and the rotor; the stator is formed by coupling a plurality of single-tooth stator cores 1, and each single-tooth The stator core 1 and the armature winding 2 in the form of a full-tooth winding set on the stator teeth 3 form a module, and 12 modules of the same type are coupled to form a stator through the protrusions and grooves of the single-tooth stator core 1. Slot concentrated winding, stator slot 4 is formed between adjacent stator teeth 3; fractional slot concentrated winding is adopted, the winding is wound through all teeth, no jumper wire is needed, and the entire end is extremely short. Fig. 2 is a single-tooth stator core 1, one side is a convex part, and the other side is a groove, representing 30 radians.

The rotor includes a rotor core and magnetic poles, and the rotor core includes a rotor core main part 7 and a rotor core supplementary part 6; the rotor core main part 7 includes a base body and teeth arranged on the base body, which are gear-shaped as a whole, two by two There is a rotor core supplementary part 6 between the adjacent teeth, and an air-cooling channel 10 is provided between the rotor core supplementary part 6 and the base body. There are 8 magnetic poles in total, and each magnetic pole is divided into two magnets and installed separately. Between the two sides of the same rotor core supplementary part 6 and the teeth at the corresponding positions, each magnetic pole forms a figure-eight structure, in which the small end opening of the figure-eight is directed to the center of the rotor, and two adjacent magnetic poles are formed in opposite polarities. The N pole 8 and the S pole 9 are spaced apart. The figure-eight structure, its size and installation method are determined after the optimization conditions of the maximum air gap average magnetic field density and the minimum harmonics in the steady state.

In the structure of the present invention, the size of the rotor is determined after taking the minimum cogging torque as the optimization condition, and the specific process is as follows: determine the initial stator thickness, stator split ratio, the thickness of each magnetic steel, and the radian of the supplementary part of the rotor; Further adjust the above initial parameters according to the precision of the processing technology; then use the simulation software to perform simulation calculations, and finally take the minimum cogging torque as the optimization goal. Under the simulation results of the minimum cogging torque, the corresponding stator and rotor dimensions are the final plan.

The above-mentioned air-cooling channel is located between the two magnetic steels in the figure-eight structure, and is closer to the center of the rotor than the magnetic steel in the axial direction; the height of the air-cooling channel 10 is not less than the thickness of each magnetic steel, and the magnetic isolation effect is obvious; The width of the channel 10 is 1/2 of the width of a single magnetic pole.

The present invention mainly adopts technologies such as fractional slot concentrated winding, splayed structure, and modularized stator to realize the characteristics of low cogging torque, less harmonics, no end, and high power density of the motor of the invention. The modular stator structure is shown in FIG. 2 .

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (7)

1. a kind of New energy automobile motor, it is characterised in that：Using external stator internal rotor form, the stator is determined by multiple monodentates Sub- iron core (1) is coupled to form, and on the stator tooth (3) in each monodentate stator core (1) electricity of the full tooth around form is provided with Pivot winding (2), is integrally formed the centralized winding of fractional-slot after coupling；The rotor includes rotor core and magnetic pole, the rotor Iron core includes that rotor core main part (7) and rotor core supplement part (6)；The rotor core main part (7) includes Matrix and the tooth being arranged on matrix, rotor core main part (7) is in integrally gear-like, and between two two adjacent teeths one is provided with Block rotor core supplements part (6), and rotor core supplements part (6) and air-cooled passage (10), each magnetic are provided with and matrix between Pole is one block of magnet and is divided into both sides and corresponding positions that two magnet steel are separately mounted to same rotor core supplement part (6) Put between the tooth at place so that each magnetic pole forms splayed structure, wherein splay little end opening points to rotor center, it is adjacent Two pole polarities formed on the contrary N poles and S interpolars every form.

2. a kind of New energy automobile motor according to claim 1, it is characterised in that：The motor is tied using proximal pole groove motor The least common multiple of structure and pole slot number is less than or equal to 12.

3. New energy automobile motor according to claim 2, it is characterised in that：The stator adopts modularized design, It is used for two side walls of monodentate stator core (1) connection adjacent with both sides in each monodentate stator core (1), side is recessed Groove, opposite side are the tongues with matching grooves, and adjacent monodentate stator core (1) is formed completely by the combination of groove and tongue Stator structure.

4. a kind of New energy automobile motor according to claim 3, it is characterised in that：The size of the rotor is turned with teeth groove Determine after the minimum optimal conditions of square, detailed process is：It is determined that initial stator thickness, rotor split ratio, each magnet steel it is thick Degree and rotor supplement the radian of part (6)；The above each initial parameter is further adjusted according to processing technology precision；It is then sharp Simulation calculation is carried out with simulation software, finally with minimum cogging torque as optimization aim, in minimum cogging torque emulation knot Under fruit, corresponding rotor size is final scheme.

5. a kind of New energy automobile motor according to claim 3, it is characterised in that：The size of the magnet steel is with stable state Determine after the minimum optimal conditions of air gap average magnetic field density maximum harmonic of motor.

6. a kind of New energy automobile motor according to claim 3, it is characterised in that：The air-cooled passage (10) is positioned at eight In character form structure between two magnet steel, and in axial direction than magnet steel near the center of rotor；The height of air-cooled passage (10) is not less than The thickness of each magnet steel, magnetism isolating effect is obvious；Width of the width of air-cooled passage (10) less than single magnetic pole.

7. a kind of New energy automobile motor according to claim 6, it is characterised in that：Air-cooled passage (10) width is single The 1/2 of magnet pole widths.