CN106992646B

CN106992646B - Hub motor for electric vehicle

Info

Publication number: CN106992646B
Application number: CN201710219006.1A
Authority: CN
Inventors: 王加许; 丁伟; 张忠
Original assignee: TAIZHOU JINYU MOTOR CO Ltd
Current assignee: TAIZHOU JINYU MOTOR CO Ltd
Priority date: 2015-09-14
Filing date: 2015-09-14
Publication date: 2020-03-24
Anticipated expiration: 2035-09-14
Also published as: CN106992645A; CN106992646A; CN105099111B; CN105099111A; CN106992645B

Abstract

The utility model provides a brushless direct current wheel hub motor of permanent magnetism for electric motor car with high efficiency low material loss, including stator assembly and rotor assembly, stator assembly includes fixed bolster and closed assembly stator steel sheet, closed assembly stator steel sheet is folded by a plurality of silicon steel sheet and is pressed and constitute, closed assembly stator steel sheet includes tooth portion and tooth's socket portion, tooth portion includes tooth muscle and tooth yoke, tooth's socket portion comprises the inside cavity of half-closed mouth that the tooth portion formed between two liang, the monolithic silicon steel sheet is equipped with from catching groove, tooth's socket portion is the pear groove structure of half-closed mouth, be equipped with first hall groove, second hall groove and third hall groove on the closed assembly stator steel sheet, rotor assembly comprises by lieing in outlying rim, magnetic ring and a plurality of magnetic steel sheet. The invention optimizes the pole groove ratio, improves the performance, reduces the consumption of magnetic steel and enameled wire, saves the cost, optimizes the Hall groove installation position and winding mode, improves the production efficiency and enhances the installation accuracy.

Description

Hub motor for electric vehicle

The present application is a divisional application of the following applications: application date: 9 month and 14 days 2015; application No.: 201510578491.2, respectively; the invention discloses a permanent magnet brushless direct current hub motor with high efficiency and low material loss for an electric vehicle.

Technical Field

The invention relates to the technical field of electric vehicle motors, in particular to a hub motor for an electric vehicle.

Background

The motor is one of the core components of the electric vehicle, and the performance of the electric vehicle motor directly affects the safety, operability, reliability and service life cycle of the electric vehicle. The motor is based on an electromagnetic principle, takes a stator and a rotor as core elements, converts electric energy into kinetic energy or mechanical energy, and mainly outputs the kinetic energy or the mechanical energy in the form of motor rotating speed and torque.

The permanent magnet brushless direct current motor takes a permanent magnet material as a fixed magnetic pole of the motor, detects the relative position of the magnetic pole and a tooth space through a Hall element, transmits a position signal to a control device, and the control device determines the power-on and power-off sequence and the power-on and power-off time of a three-phase winding through program coding, so that a coil stator generates a rotary variable magnetic field with a certain rule, unbalanced magnetic field torque is formed, and the motor can generate directional rotation. However, the existing motor is limited by an internal space structure, and the matching size relationship between the stator and the rotor is unreasonable, so that the energy conversion efficiency and the overall output performance of the motor are influenced. Because the rare earth magnetic pole material has the characteristics of large magnetic energy product, strong demagnetization resistance, high temperature resistance and the like, the volume of the motor can be greatly reduced, and the internal structure of the motor is simplified, so that the rare earth magnetic pole material is adopted by most brushless direct current motors, but the magnetic field variability of the motor and certain performance requirements of the motor which are required to be obvious are different, so that all magnetic energy cannot be completely utilized, the utilization rate of the magnetic pole material is low, the rare earth magnetic pole material is scarce and expensive, and the integral manufacturing cost is high; on the other hand, the existing motor stator tooth slot structure is poor in design, and on the basis of ensuring the output characteristic of the motor, the defects that the using amount of copper wires is high, the copper loss and the iron loss of the stator are high, the magnetic energy utilization rate of magnetic poles is low and the like exist. In all aspects, the internal structure of the existing motor has the defects of low motor conversion efficiency, insufficient output torque, large material consumption and the like.

Disclosure of Invention

The invention aims to solve the problem of complaints and provides a hub motor for an electric vehicle, which has the characteristics of reasonable structure, high utilization rate of internal space, high motor conversion efficiency, large output torque, less material consumption, low copper loss and iron loss and high magnetic energy utilization rate.

The technical problem solved by the invention can be realized by adopting the following technical scheme:

the utility model provides a brushless direct current wheel hub motor of permanent magnetism for electric motor car with high efficiency low-material loss, includes stator assembly and rotor assembly, stator assembly includes fixed bolster and closed assembly stator steel sheet, closed assembly stator steel sheet is folded by a plurality of silicon steel sheet and is pressed and constitute, closed assembly stator steel sheet includes tooth portion and tooth slot portion, tooth portion by the tooth muscle and with the yoke of tooth muscle body coupling constitutes, tooth slot portion comprises the half-closed internal cavity that tooth portion formed between two liang, the monolithic the silicon steel sheet can be equipped with from catching groove, tooth slot portion is half-closed pear groove structure, be equipped with first hall groove, second hall groove and third hall groove on the closed assembly stator steel sheet, first hall groove with second hall groove is located respectively on tooth muscle central line one side position, third hall groove is located tooth groove central line department, third hall groove respectively with hall contained angle that forms between first hall groove and the second hall groove is 11 degrees contained angles 12 degrees, the rotor assembly is composed of a rim positioned on the periphery, a magnetic conduction ring arranged on the inner circumference of the rim and a plurality of magnetic steel sheets attached to the inner circumference of the magnetic conduction ring, the thickness of each magnetic steel sheet is 2.2-2.3mm, and an air gap is formed between each magnetic steel sheet and each silicon steel sheet.

A shaft sleeve is fixedly welded at the center of the fixed support, and a motor shaft is connected in the shaft sleeve in an interference manner.

The outer diameter of the stacked stator steel sheet is 203.3-203.5mm, the silicon steel sheet is a non-oriented silicon steel sheet, the width of a tooth rib is 6.0-7.0mm, the height of a tooth yoke is not less than 4.6mm, the groove shoulder angle of the stacked stator steel sheet is 115-120 degrees, and the groove opening width of the tooth groove is 2.2-2.6 mm.

The laminated stator steel sheet is composed of a plurality of layers of silicon steel sheets laminated by single punching sheets, and the width of a slot opening of the tooth socket part is 2.2-2.3 mm.

The stacked stator steel sheet is formed by punching silicon steel sheets, material strips and winding, and the width of a slot opening of the tooth socket part is 2.4-2.6 mm.

The number of the tooth groove parts is 48.

The third Hall groove and the first Hall groove and the second Hall groove respectively form a Hall mechanical included angle with the best angle of 11 degrees 32', Hall elements are respectively arranged in the first Hall groove, the second Hall groove and the third Hall groove, and the Hall elements are formed by welding a PCB (printed Circuit Board) Hall circuit board or hand welding wires.

The optimal thickness of the magnetic steel sheets is 2.3mm, a plurality of magnetic steel sheets are evenly distributed in an N-S-N-S circulation mode, the number of the magnetic steel sheets is 52, and the magnetic steel sheets are of cuboid structures.

Stator windings are arranged in the tooth groove portions and are of a double-layer winding structure.

The stator winding adopts a fractional slot concentrated winding structure, the anticlockwise direction of the side face of the Hall element mounting surface is taken as a winding wiring direction, the front 3 slots of the third Hall slot in the circumferential winding trend are selected as initial wire inlet slots, the winding is wound in an anticlockwise winding mode by using an initial tooth socket, the winding pitch is 1, each phase is wound with 16 teeth, 4 teeth are concentrated into one group, the concentrated winding is connected in series to form a branch, and the stator winding is welded at the wire outlet end of each phase by a Y-shaped structure.

Compared with the prior art, the invention has the following outstanding advantages and effects: according to the invention, by optimizing the pole slot proportioning structure and adopting 48 slots for proportioning 52 poles, the short distance coefficient is improved, the using amount of copper wires is reduced, the stator winding can conveniently complete winding in a fractional slot concentrated double-layer winding mode, the cogging torque of the motor is effectively reduced, and the conversion efficiency of the motor is improved; the use amount of magnetic steel rare earth materials is reduced by increasing the outer diameter of the stator and reducing the thickness of the magnetic steel sheet, and the use amount is generally lower than that of motors with the same specification, so that the manufacturing cost is saved; the trough shape of the tooth socket part adopts a pear-shaped structure, the utilization rate of silicon steel sheet materials is improved by utilizing the magnetic circuit saturation principle, the trough shape of the structure is respectively designed according to the magnetic circuits, the trough area is enlarged, the winding is favorably wound, reasonable copper wires are conveniently adopted, and the torque output is improved; the installation position of the Hall groove is optimized, the Hall groove structure on one side of the central line of the tooth is offset by the Hall grooves on the 2 tooth parts, so that the included angle of the Hall groove is optimized and improved, the three-phase equal division of the phase angle of the motor is ensured, the span of the three Hall grooves is short, the method is suitable for mass production of PCB concentrated welding wires, the production efficiency is improved, the installation accuracy is increased, and meanwhile, the adjustable span of the rotating speed and the power is increased by matching with the fractional groove concentrated winding structure of the stator winding; the tooth space part structure is optimized, and the overall performance is improved on the premise of ensuring the output of the rotating speed and the torque. The invention has the characteristics of reasonable structure, high utilization rate of internal space, high conversion efficiency of the motor, strong output torque, material consumption saving, low copper loss and iron loss and high utilization rate of magnetic energy.

The features of the present invention will be apparent from the accompanying drawings and from the detailed description of the preferred embodiments which follows.

Drawings

FIG. 1 is a schematic view of a stator assembly and a rotor assembly mounting structure according to an embodiment of the present invention;

FIG. 2 is an enlarged view of a portion A of FIG. 1;

FIG. 3 is an overall cross-sectional structural schematic view of an embodiment of the present invention;

FIG. 4 is a schematic diagram of an arrangement structure of magnetic steel sheets according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a stator winding fractional-slot concentrated winding structure according to an embodiment of the invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.

As shown in fig. 1 to 5, the hub motor for an electric vehicle provided by the invention comprises a stator assembly and a rotor assembly, wherein the stator assembly comprises a fixed support 2 and a stacked stator steel sheet 1, a shaft sleeve 21 is welded and fixed at the center of the fixed support 2, a motor shaft 22 is connected in the shaft sleeve 21 in an interference fit manner, the outer diameter of the stacked stator steel sheet 1 is 203.3-203.5mm, the outer diameter size of the stacked stator steel sheet 1 is increased, the utilization rate of an internal space is improved, the stacked stator steel sheet is formed by laminating a plurality of silicon steel sheets, the stacked stator steel sheet 1 comprises a tooth part 11 and a tooth space part 12, the tooth part 11 comprises a tooth rib 111 and a tooth yoke 112 integrally connected with the tooth rib 111, the tooth space part 12 is formed by a semi-closed internal cavity formed between the tooth parts 11, the width of the tooth rib 111 is 6.0-7.0mm, the height of the tooth yoke 112 is not less than 4.6mm, the slot angle of the stacked stator 1 is 115-120 degrees, and the slot width of the shoulder 12 is 2.2, the silicon steel sheets are non-oriented silicon steel sheets, the single silicon steel sheet is provided with self-buckling grooves, the self-buckling grooves arranged in the silicon steel sheets are utilized through optimizing a tooth socket structure, so that the silicon steel sheets are conveniently buckled and the flatness of integral stacking is increased, and meanwhile, the stacking height of the structure can be correspondingly adjusted according to different output rotating speeds and output torques and according to different power requirements; the number of the grooves in the tooth groove part 12 is 48, the tooth groove part 12 is of a semi-closed pear-shaped groove structure, the structure improves the material utilization rate of silicon steel sheets, enlarges the groove area, is beneficial to winding of a stator winding, and meanwhile, the groove area with a larger area can contain reasonable copper wires, thereby being beneficial to improving the output of torque; a stator winding is arranged in the plurality of tooth groove portions 12, the stator winding is of a double-layer winding structure, the stator winding adopts a fractional groove concentrated winding structure, the inlet end and the outlet end of a three-phase line of the stator winding are arranged on the same side, Hall elements are arranged on the other side of a silicon steel sheet and distributed on two sides, the anticlockwise direction seen from the side face of a Hall element mounting surface is taken as the winding routing direction, the first 3 grooves of the third Hall groove in the circumferential winding direction are selected as initial inlet grooves, the winding is wound with the initial tooth grooves in the anticlockwise direction, the winding pitch is equal to 1, 16 teeth are wound on each phase, 4 teeth are concentrated in one group, the concentrated winding is connected in series to form a branch, and the stator winding is welded with the outlet end of each; the laminated stator steel sheet 1 is provided with a first Hall groove 13, a second Hall groove 14 and a third Hall groove 15, the first Hall groove 13 and the second Hall groove 14 are respectively positioned on one side of the central line of the tooth rib 11, and have an angle deviation with the central line, the third Hall groove 15 is positioned at the central line of the notch of the tooth groove part 12, the Hall included angle formed between the third Hall groove 15 and the first Hall groove 13 and the second Hall groove 14 is 11-12 degrees, the Hall included angle is optimized by reasonably calculating the relation between the magnetic potential phase angle and the mechanical angle of the tooth groove part 12, the three-phase angle of the motor can be adjusted, and the three phases of the three-phase angle can be uniformly divided; hall elements are respectively arranged in the first Hall groove 13, the second Hall groove 14 and the third Hall groove 15, the Hall elements are formed by welding or hand welding of a PCB Hall circuit board, and can be welded with a motor with a phase angle of 60 degrees or 120 degrees; the rotor assembly is composed of a rim 3 positioned on the periphery, a magnetic conductive ring 4 arranged on the inner circumference of the rim 3 and a plurality of magnetic steel sheets 5 attached to the inner circumference of the magnetic conductive ring 4, the thickness of the magnetic steel sheets 5 is 2.2-2.3mm, the use amount of magnetic steel rare earth materials is reduced by reducing the thickness of the magnetic steel sheets 5, the magnetic steel sheets are made of neodymium iron boron 38MT materials, the residual magnetism Br of magnetic steel is 1220-1250mT, the coercive force Hcb is not less than 899kA/m, the intrinsic coercive force Hcj is not less than 1114kA/m, the maximum magnetic energy product (BH) max of the material is 287-310kJ/m3 ℃, the highest working temperature can reach 120 ℃, and the manufacturing cost is saved; the magnetic steel sheets 5 are evenly distributed in an N-S-N-S circulation mode, the magnetic steel sheets 5 are of cuboid structures, air gaps are formed between the magnetic steel sheets 5 and silicon steel sheets, the number of the magnetic steel sheets 5 is 52, the tooth groove part 12 structure of 48 grooves is matched, the polar groove matching structure is optimized, and the precise thickness reduction of the magnetic steel sheets 5 can be completed under the matching structure.

The closed loop route of the magnetic field related by the invention is as follows: the magnetic pole N-air gap-tooth rib-tooth yoke-tooth rib-air gap-antipodal magnetic pole S-antipodal magnetic pole N-magnetic conductive ring-magnetic pole S form a closed magnetic circuit.

Example 1

According to the integral structure, the laminated stator steel sheet 1 is formed by a plurality of silicon steel sheets in a single sheet punching lamination shape, the width of a slot opening of a tooth groove part 12 is 2.2-2.3mm, the optimal Hall included angle formed between a third Hall groove 15 and a first Hall groove 13 and a second Hall groove 14 is 11 degrees 32 degrees, and the optimal thickness of a magnetic steel sheet 5 is 2.3 mm.

Example 2

According to the integral structure, the stacked stator steel sheet 1 is formed by punching silicon steel sheets, material strips and winding, the width of a slot opening of the tooth socket part 12 is 2.4-2.6 mm, the optimal Hall included angle formed between the third Hall groove 15 and the first Hall groove 13 and the second Hall groove 14 is 11 degrees 32 degrees, and the optimal thickness of the magnetic steel sheet 5 is 2.3 mm.

According to the invention, a pole slot proportioning structure with 48 slots in 52-pole proportioning is adopted, the outer diameter of the stacked stator steel sheets is increased by precisely reducing the thickness of the magnetic steel sheets, the internal structure is optimized, the internal space is fully utilized, the use amount of the magnetic steel sheets is reduced, the utilization rate of magnetic steel sheet materials is increased, the cost is reduced, and the use performance of the motor is increased; the magnetic circuit saturation principle is utilized, the tooth space structure is reasonably optimized, the reasonable size range is combined, the semi-closed pear-shaped groove structure is adopted, the utilization rate of the silicon steel sheet material is improved, reasonable copper wires are conveniently selected by enlarging the groove area, the winding of the copper wires to complete stator winding is facilitated, the short distance coefficient is improved, the using amount of the copper wires is reduced, the output of torque is facilitated to be improved, meanwhile, the groove type structure is suitable for various pole groove ratios and winding structures, and the adjustable range of the rotating speed and the power is improved; the installation position of the Hall groove is optimized, the Hall groove structure on one side of the central line of the tooth is offset by the Hall grooves of 2 tooth parts, and the mechanical included angle of the Hall grooves is optimized, the improvement of the structure is favorable for meeting the requirement of adjusting the three-phase angle of the motor, the Hall groove span is short, the concentrated welding line of a PCB (printed circuit board) is convenient for mass production, the production process is optimized, and meanwhile, the special winding structure of a stator winding is matched, so that the adjustable span of the rotating speed and the power is increased, and the three-phase even distribution of the phase; the stator winding adopts a double-layer winding structure, and improves the service performance of the motor by utilizing a stator fractional slot concentrated winding structure and an air gap flux density waveform fit sine distribution.

The invention has the advantages of high-efficiency electromagnetic path, excellent output torque performance, compact and reasonable structure, high utilization rate of internal space, excellent use performance, high utilization rate of rare earth materials, low copper loss and iron loss, material consumption conservation and high utilization rate of magnetic energy.

It will be appreciated by those skilled in the art that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed above are therefore to be considered in all respects as illustrative and not restrictive. All changes which come within the scope of or equivalence to the invention are intended to be embraced therein.

Claims

1. The hub motor for the electric vehicle is characterized by comprising a stator assembly and a rotor assembly, wherein the stator assembly comprises a fixed support and stacked stator steel sheets, each stacked stator steel sheet comprises a tooth part and a tooth groove part, each tooth groove part is formed by a semi-closed inner cavity formed between every two tooth parts, and each tooth part comprises a tooth rib and a tooth yoke; the rotor assembly comprises a rim, magnetic conductive rings and magnetic steel sheets, the magnetic conductive rings are positioned on the inner circumference of the rim, the inner circumference of the magnetic conductive rings is provided with a plurality of magnetic steel sheets, the magnetic steel sheets are uniformly distributed in an N-S-N-S circulation mode, and a magnetic field closed loop between the stator assembly and the rotor assembly is as follows: magnetic pole N-air gap-tooth bar-tooth yoke-tooth bar-air gap-opposite magnetic pole S-opposite magnetic pole N-magnetic conductive ring-magnetic pole S;

the stacked stator steel sheet is provided with a first Hall groove, a second Hall groove and a third Hall groove, the first Hall groove and the second Hall groove are positioned on the tooth bar, the third Hall groove is positioned in a notch of the tooth groove part, Hall elements are respectively arranged in the first Hall groove, the second Hall groove and the third Hall groove, and the Hall elements are formed by welding a PCB (printed Circuit Board) Hall circuit board or a manual welding wire;

the first Hall groove and the second Hall groove are respectively positioned on one side of the central line of the tooth bar, the third Hall groove is positioned on the central line of the notch of the tooth socket, and Hall included angles formed between the third Hall groove and the first Hall groove and between the third Hall groove and the second Hall groove are 11-12 degrees;

a stator winding is arranged in the tooth space part, the stator winding adopts a fractional slot concentrated winding structure, the anticlockwise direction of the side surface view direction of the Hall element mounting surface is taken as a winding wiring direction, the front 3 slots of the third Hall slot in the circumferential winding trend are selected as initial wire inlet slots, the winding is performed by winding teeth anticlockwise around the initial tooth slots in a mode that the winding pitch is 1, each phase is wound with 16 teeth in total, 4 teeth are concentrated to form a group, a branch is formed by connecting the 4 teeth in series, and the stator winding is welded at the wire outlet end of each phase of the winding in a Y-shaped structure;

the stator winding adopts a double-layer winding structure.

2. The in-wheel motor for an electric vehicle according to claim 1, wherein the width of the notch of the tooth groove portion is 2.2-2.6 mm.

3. The in-wheel motor for an electric vehicle of claim 1, wherein the pole-slot ratio structure of the in-wheel motor comprises 48 slots with 52 magnetic steel sheets.

4. The in-wheel motor for an electric vehicle according to claim 2, wherein the width of the tooth rib is 6.0 to 7.0 mm.

5. An in-wheel motor for an electric vehicle according to any of claims 1, 2 or 4, wherein the height of the tooth yoke is 4.6mm or more.

6. The in-wheel motor for electric vehicles according to claim 3, wherein the thickness of the magnetic steel sheet is 2.2-2.3 mm.

7. The in-wheel motor for electric vehicle according to claim 6, wherein the stacked stator steel sheets have an outer diameter of 203.3-203.5 mm.

8. The in-wheel motor for electric vehicle according to claim 1, wherein the laminated stator steel sheet comprises a plurality of silicon steel sheets laminated with each other, and the silicon steel sheets are provided with self-fastening grooves.

9. The in-wheel motor for electric vehicle according to claim 8, wherein an air gap is provided between the magnetic steel sheet and the silicon steel sheet.

10. The in-wheel motor for electric vehicles according to claim 5, wherein the laminated stator steel sheets have an inter-slot angle of 115 ° to 120 °.

11. The in-wheel motor for an electric vehicle of claim 3, wherein the tooth trough portion has a semi-closed pear-shaped trough structure.