CN110198111B - Three-phase permanent magnet DC brushless motor for driving electric truck - Google Patents

Abstract

Three-phase permanent magnet brushless DC motor for electric truck drive, consisting of front-end housing, rear-end housing, rotating shaft, front-end heat dissipation frame, middle frame bracket, rear heat dissipation frame, front-end PCB circuit board, rear-end PCB circuit board, and cooling water pipe , The front-end stator core body, the front-end wire wrap, the front-end rotor core body, the front-end permanent magnet, the rear-end stator core body, the back-end wire wrap, the back-end rotor core body, and the rear-end permanent magnet are composed of a dual electromagnetic The drive and dual electronic circuits are driven synchronously, and the cooling water pipe is combined into one design scheme. The cooling water pipe is wound around the arc-shaped cooling water pipe grooves on the front and rear stator iron cores in turn. The single drive shaft, double electronic circuit drive and energy management scheme can complete the control of the three-phase permanent magnet DC brushless motor for electric truck drive without the need of an external motor controller, and realize the high torque and high power required for the operation of the electric truck output. The market outlook is promising.

Description

Three-phase permanent magnet brushless DC motor for electric truck drive

technical field

The invention relates to a three-phase permanent magnet DC brushless motor with dual electromagnetic driving and dual electronic circuit driving combined into one, which is mainly applied to the driving of electric trucks with manned or unmanned driving.

Background technique

Before proposing this invention patent design, the inventor has already felt a very obvious change in the electric vehicle industry, that is, trucks driven by internal combustion engines have also begun to develop to battery-driven electric trucks for a long time, and drive motors have begun to change from AC induction motors to Permanent magnet motor direction change. The most representative is Tesla, an electric car company named after the "father of alternating current" Tesla, which claims to build cars in the way of Internet thinking. It has launched standard Model S and Model X electric sedans. All are driven by AC induction motors, which are all the rage. However, since Tesla launched the Semi series semi-trailer all-electric trucks, the drive motor has been changed to a permanent magnet motor. According to public information, four independent permanent magnet motors are installed on the rear axle of the Semi all-electric truck, with a rated power of 271 horsepower, and the total output power of the four motors is 1084 horsepower. Driven by such strong horsepower, an empty Tesla Semi electric truck can accelerate from zero to 100 kilometers in 5 seconds, and when loaded with 36 tons, the Semi electric truck can accelerate from zero to 100 kilometers in 20 seconds.

Of course, this is not the only goal that Tesla engineers are pursuing. The biggest innovation of electric trucks is to completely change the energy consumption structure of fuel vehicles, and no longer need an engine. Therefore, electric trucks travel environmentally friendly and there is no exhaust emission problem. Shuttle in the city will not bring waste gas pollution, very suitable for postal, logistics, moving companies for short- and medium-distance cargo transportation.

On the other hand, the energy efficiency of electric trucks is much higher than that of diesel trucks, and electric trucks are more energy efficient than diesel trucks. The American Cummins Company has specially calculated the fuel efficiency of diesel trucks and concluded that the engine loss of diesel trucks is 58%, and the loss of electric truck motors is only 14%.

Today, Tesla has changed the drive motor from an AC induction motor to a permanent magnet motor, which is actually an arrangement that keeps pace with the times. After all, the permanent magnet motor direct drive technology is the next-generation drive technology recognized by the industry. Due to the high magnetic energy product and coercive force of NdFeB material and no need for excitation current, the volume of the three-phase permanent magnet brushless DC motor using NdFeB material is one frame smaller than that of the asynchronous AC induction motor of the same capacity. No., but also more energy-efficient than AC motors. The above is the real reason why three-phase permanent magnet brushless DC motors replace AC induction motors and are used in electric trucks.

It should be noted that the inventors are also not fully aware of Tesla's technical details about the permanent magnet motor used in the Semi all-electric truck, as these technical details are currently kept secret by Tesla. However, the starting price of Tesla Semi is as high as 180,000 US dollars, which is about 18*6.9=1.242 million yuan at the current price of RMB. Considering from the perspective of the customer's economic operation, how to reduce the cost of the electric truck provides a broad innovation space for the design of the present invention.

The inventor secretly believes that the solution of directly driving electric trucks with an independent permanent magnet motor must have removed the front axle or rear axle, and used the electronic differential method to directly control the in-wheel motors. Perhaps this is the main reason for the soaring cost of electric trucks. one. From the perspective of the most economical and overall optimal system, if only one three-phase permanent magnet brushless motor is used to drive the electric truck, the power will be stretched. More importantly, when a single three-phase permanent magnet brushless motor is applied to the drive of a freight truck, the biggest problem is still how to dissipate heat inside the motor and drive control. Especially when the rotating torque of the electric truck increases, the shear stress on the rotor will be greater, and the fatigue strength of the NdFeB permanent magnet material as the main component will decrease, and the possibility of damage will also increase. To implement protection, a topological solution must be found; on the other hand, when the temperature of the armature coil is higher than about 150 °C, the temperature of the motor casing will rise to about 100 °C, and the enameled wire will be over 150 °C when the temperature is higher than the paint film will be. It falls off due to excessive temperature, resulting in a short circuit in the internal circuit of the wire package. This temperature is equivalent to the temperature of the B-class insulation material of the motor. More importantly, the demagnetization temperature of NdFeB permanent magnet materials can reach 140 °C. When the temperature of the motor is higher than 150 °C, the electromagnetic circuit of the motor is bound to have magnetic saturation, and the NdFeB permanent magnet material is bound to occur more than 5%. irreversible magnetic loss. This is not only the bottleneck of the permanent magnet, but also one of the problems that the application of the present invention focuses on solving.

In view of the above background materials, the present application specifically proposes a design scheme for driving an electric truck with a three-phase permanent magnet brushless motor, aiming at various characteristics of the three-phase permanent magnet brushless DC motor used for electric truck driving. This design scheme changes the traditional practice of three-phase permanent magnet brushless motor with single stator and electric control drive, through the heat dissipation structure of double stator, double rotor, single rotating shaft, double electronic circuit synchronous double push drive, and cooling water pipe. With the multi-pronged approach of energy management, in addition to obtaining larger power output, there is no need for an external motor controller, which highlights the most economical and overall optimal features of the system; especially in the three-phase permanent magnet brushless DC The motor is embedded with an energy management circuit, which significantly improves the efficiency and reliability of the motor, and successfully solves the problem of insufficient power that may be caused by a single three-phase permanent magnet brushless motor driving an electric truck.

SUMMARY OF THE INVENTION

Accordingly, the present invention proposes a design scheme of a three-phase permanent magnet DC brushless motor for electric truck driving. For electric trucks that are frequently started and stopped, constant torque is required when running at high speed, and constant torque is required when running at low speed. The working condition of constant power is particularly effective. The specific technical solutions are as follows:

Three-phase permanent magnet brushless DC motor for electric truck drive, consisting of front-end housing, rear-end housing, rotating shaft, front-end heat dissipation frame, middle frame bracket, rear heat dissipation frame, front-end PCB circuit board, rear-end PCB circuit board, and cooling water pipe , The front-end stator core body, the front-end wire wrap, the front-end rotor core body, the front-end permanent magnet, the rear-end stator core body, the back-end wire wrap, the rear-end rotor core body, and the rear-end permanent magnet components. The main points are:

The three-phase permanent magnet DC brushless motor for driving electric trucks adopts a topology structure in which dual electromagnetic drives and dual electronic circuits are synchronously driven, plus cooling water pipes are combined into one. In the casing jointly surrounded by the rear casing, the rotating shaft protrudes from the central hole of the front casing;

The dual electromagnetic drive part includes a front-end stator core body, a front-end wire package, a front-end rotor core body, a front-end permanent magnet and a rear-end stator core body, a rear-end wire package, a rear-end rotor core body, and a rear-end permanent magnet. The front-end stator core body and the rear-end stator core body are made of cold-rolled silicon steel punching sheets superimposed. The edge of the front-end stator core body is provided with an arc-shaped cooling water pipe groove A, and the edge of the rear-end stator core body is opened. There is an arc cooling water pipe groove B;

The front-end rotor core body and the rear-end rotor core body are both made of cold-rolled silicon steel punching sheets, and annular grooves are punched near the edges of the front-end rotor core body and the rear rotor core body. The front-end permanent magnets and the rear-end permanent magnets are made of NdFeB magnetic materials, sintered into concentric unequal-circle magnetic steel tiles, and then embedded in the annular grooves on the front-end rotor core body and the rear-end rotor core body respectively;

The dual electronic circuit driving part includes a front-end PCB circuit board, a front-end heat dissipation frame and a rear-end PCB circuit board, and a rear-end heat dissipation frame. Cavity structure, the front heat dissipation frame protrudes from the front heat dissipation frame legs, and the rear heat dissipation frame protrudes from the rear heat dissipation frame legs;

The front-end PCB circuit board has a hexagonal structure, and is welded with a front-end ARM chip, a front-end driver chip, a front-end VMOS tube, an energy management chip, a power three-terminal device, and a power inductor. At the fan-shaped boss of the front heat dissipation frame in the front heat dissipation frame;

The back-end PCB circuit board is a hexagonal structure, on which the back-end ARM chip, the back-end VMOS tube, the back-end driver chip, the synchronous interlock chip, and the temperature sensor are welded, and then the back-end PCB circuit board is installed on the back-end to dissipate heat. At the fan-shaped boss of the rear heat dissipation frame in the frame;

The front-end ARM chip and the back-end ARM chip communicate through their respective I/O ports, and release the permit or prohibit command through the synchronous interlock chip to synchronously control the front-end driver chip and the back-end driver chip. The front-end driver chip pushes the front-end VMOS tube, and the rear The end driver chip drives the back end VMOS tube;

The energy management chip on the front-end PCB circuit board can detect the U, V, W three-phase current signals, and the temperature sensor on the back-end PCB circuit board is used to detect the working environment temperature of the motor. When balanced and overheated, the synchronous interlock chip immediately releases the inhibit signal, and locks off the front-end VMOS tube and the back-end VMOS tube at the same time;

The middle frame support is a ring with a hole in the middle, the edges of the ring respectively protrude the middle frame support legs, one end of the front stator iron core body is connected with the middle frame support legs, and the other end of the front end stator iron core body is connected. Connect with the front end of the heat dissipation frame, one end of the rear stator core body is connected with the middle frame support leg, and the other end of the rear stator core body is connected with the rear heat dissipation frame leg;

The cooling water pipe is a round copper water pipe. After passing through the cooling water pipe hole of the middle frame bracket, the middle part of the copper water pipe is integrated with the middle frame bracket, and one end of the copper water pipe extends and is embedded in the edge of the front stator core body. In the arc-shaped cooling water pipe groove A, the other end of the copper water pipe is extended and embedded in the arc-shaped cooling water pipe groove B on the edge of the rear rotor core body;

The middle part of the rotating shaft is a cylindrical iron core body, and there are two embedded grooves on the cylindrical iron core body. The cylindrical iron core body is embedded in two grooves to form a rotor as a whole.

The cooling water pipe has a water inlet port and a water outlet port, the water inlet port passes through the water inlet port on the front shell and then extends out of the motor, and the water outlet port passes through the water outlet port on the rear shell to open. The groove extends to the outside of the motor, and the water inlet pipe is connected to an external frequency conversion speed-regulated water pump.

The rotating shaft is embedded with a front bearing and a rear bearing, the front bearing is embedded in a step in the front end housing for fixation, and the rear bearing is embedded in a step in the rear end housing for fixation.

Further, the front-end wire wraps and the back-end wire wraps both use oxygen-free enameled copper wires with a conductivity of 109.0% electrolytic copper.

Further, the front-end housing is provided with a front-end wire outlet hole, and the rear-end housing is provided with a rear-end wire outlet hole.

Further, the front heat dissipation frame and the rear heat dissipation frame are made of aluminum alloy, and the middle frame support is made of heat-resistant engineering plastics.

During assembly, the front VMOS tube is connected to the VMOS tube fixing hole C through screws, and the rear VMOS tube is connected to the VMOS tube fixing hole D through screws.

Description of drawings

Fig. 1 Outline drawing 1 of the three-phase permanent magnet brushless DC motor for electric truck drive;

Fig. 2 Structure exploded view 1 of three-phase permanent magnet brushless DC motor for electric truck drive;

Fig. 3 Structure exploded view 2 of three-phase permanent magnet brushless DC motor for electric truck drive;

Figure 4. Exploded view 1 of the internal structure after removing the front-end shell and the rear-end shell;

Fig. 5 Exploded view 2 of the internal structure after removing the front-end shell and the rear-end shell;

Figure 6 Exploded view 3 of the internal structure after removing the front-end shell and the rear-end shell;

Figure 7 Exploded view of the internal structure after removing the front and rear housings;

Figure 8 Exploded view of the internal structure after removing the front and rear housings;

Figure 9 Exploded view 6 of the internal structure after removing the front and rear housings;

Fig. 10 Exploded view 7 of the internal structure after removing the front-end housing and the rear-end housing;

Figure 11 Exploded view 8 of the internal structure after removing the front and rear housings;

Figure 12 Exploded view of the internal structure after removing the front and rear housings;

Figure 13 Exploded view 10 of the internal structure after removing the front and rear housings;

Figure 14 Front-end PCB circuit board and rear-end PCB circuit board outline drawing 1;

Figure 15 Front-end PCB circuit board and rear-end PCB circuit board outline drawing 2;

Figure 16 Outline drawing of the middle frame bracket;

Figure 17 Outline drawing of the front end iron core body, the front end rotor iron core body and the rotating shaft;

Figure 18 Outline drawing of rotating shaft, front rotor core body and rear rotor core body;

Fig. 19 An exploded view of the structure of the rotating shaft, the front rotor core body, and the rear rotor core body.

Label description:

1 Front housing

11 Front cable outlet

13 Slotted water inlet pipe

2 rear housing

21 Rear cable outlet

23 Slotted outlet pipe

3 Rotary axis

31 Front bearing

32 rear bearing

33 Groove

4 Front cooling frame

41 Front cooling frame feet

42 Fan-shaped bosses of the front cooling frame

43 VMOS tube fixing hole C

5 Rear cooling frame

51 Rear cooling frame feet

52 Fan-shaped bosses of the rear cooling frame

53 VMOS tube fixing hole D

6 Front end stator core

61 Front end cable package

62 Front rotor core body

63 Front end permanent magnet

64 Front rotor core body boss

65 Arc cooling water pipe groove A

7 Middle frame bracket

71 Cooling water pipe

72 Water inlet pipe

73 Water outlet

74 Hole for cooling water pipe of middle frame bracket

75 Middle frame bracket feet

8 Rear stator core body

81 Rear Wire Pack

82 Rear rotor core body

83 Rear permanent magnet

84 Rear end rotor core body boss

85 Curved cooling water pipe groove B

9 Front-end PCB circuit board

91 Front-end ARM chip

92 Front-end driver chip

93 Front-end VMOS tube

94 Energy management chip

95 Power Three-Terminal Devices

96 Power Inductors

10 Back-end PCB circuit board

101 Back-end ARM chip

102 Back-end VMOS tube

103 Back-end driver chip

104 Synchronous interlock chip

105 Temperature sensor

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and the embodiments thereof.

In this embodiment, a three-phase permanent magnet brushless DC motor for driving an electric truck is composed of a front end casing (1), a rear end casing (2), a rotating shaft (3), a front end heat dissipation frame (4), and a middle frame bracket (7). ), rear heat dissipation frame (5), front PCB circuit board (9), rear PCB circuit board (10), cooling water pipe (71), front stator core body (6), front wire package (61), front end Rotor iron core body (62), front end permanent magnet (63), rear end stator iron core body (8), rear end wire wrap (81), rear end rotor iron core body (82), rear end permanent magnet (83) components composition, the main points of which are:

The three-phase permanent magnet DC brushless motor for driving electric trucks adopts a topology structure in which dual electromagnetic drives and dual electronic circuits are synchronously driven, and cooling water pipes are combined into one. 1) In the casing enclosed by the rear casing (2), the rotating shaft (3) protrudes from the central hole of the front casing (1);

The dual electromagnetic drive part includes a front-end stator core body (6), a front-end wire wrap (61), a front-end rotor core body (62), a front-end permanent magnet (63), a rear-end stator core body (8), and a rear-end wire wrap (81), the rear rotor core body (82), the rear permanent magnet (83), the front stator core body (6) and the rear stator core body (8) are both punched from cold-rolled silicon steel. The edge of the front stator core body (6) is provided with an arc-shaped cooling water pipe groove A (65), and the edge of the rear stator core body (8) is provided with an arc-shaped cooling water pipe groove B (85);

The front-end rotor core body (62) and the rear-end rotor core body (82) are both made of cold-rolled silicon steel punching sheets, and the front-end rotor core body (62) and the rear-end rotor core body (82) ) near the edge are punched with annular grooves, the front-end permanent magnet (63) and the rear-end permanent magnet (83) are made of NdFeB magnetic materials, sintered into concentric unequal-circle magnetic steel tiles, and then embedded in the front ends respectively In the annular grooves on the rotor core body (62) and the rear rotor core body (82), this arrangement can protect the fragile NdFeB permanent magnet material and greatly reduce the impact of shear stress on it under high torque , and the rotor core itself with good heat transfer can help it dissipate heat quickly;

The dual electronic circuit driving part comprises a front-end PCB circuit board (9), a front-end heat dissipation frame (4), a rear-end PCB circuit board (10), a rear-end heat dissipation frame (5), and the front-end heat dissipation frame (4) and the rear end The heat dissipation frame (5) is a cavity structure with a circular outside and a hexagonal inside. The front heat dissipation frame (4) protrudes from the front heat dissipation frame legs (41), and the rear heat dissipation frame (5) protrudes from the rear end. heat dissipation frame feet (51);

The front-end PCB circuit board (9) has a hexagonal structure, and is welded with a front-end ARM chip (91), a front-end driver chip (92), a front-end VMOS tube (93), an energy management chip (94), and a three-terminal power supply. device (95), power inductor (96), and then the front-end PCB circuit board (9) is mounted on the front-end heat-dissipating frame fan-shaped boss (42) in the front-end heat-dissipating frame (4);

The back-end PCB circuit board (10) has a hexagonal structure, and is soldered with a back-end ARM chip (101), a back-end VMOS tube (102), a back-end driver chip (103), a synchronous interlock chip (104), a temperature sensor (105), and then install the rear-end PCB circuit board (10) on the rear-end heat-dissipating frame fan-shaped boss (52) in the rear-end heat-dissipating frame (5);

The front-end ARM chip (91) communicates with the back-end ARM chip (101) through respective I/O ports, and then the I/O port of the back-end ARM chip (101) controls the synchronous interlock chip (104) to release synchronously Allow or prohibit commands to control the front-end driver chip (92) and the back-end driver chip (103), the front-end driver chip (92) drives the front-end VMOS transistor (93), and the back-end driver chip (103) drives the back-end VMOS transistor (102) ;

The energy management chip (94) on the front-end PCB circuit board (9) detects the U, V, W three-phase current signals, and the temperature sensor (105) on the back-end PCB circuit board (10) detects the working environment temperature of the motor. In case of surge overcurrent, unbalanced three-phase current and overheating, the synchronous interlock chip (104) immediately releases the prohibition signal, and locks off the front-end VMOS tube (93) and the rear-end VMOS tube (102) at the same time;

The middle frame bracket (7) is a ring with a hole in the middle, and the middle frame bracket legs (75) protrude from the edges of the ring respectively. During assembly, one end of the front stator core body (6) is connected to the middle frame bracket The legs (75) are connected to each other, the other end of the front stator core body (6) is connected to the front heat dissipation frame legs (41), and one end of the rear stator core body (8) is connected to the middle frame bracket legs (75). , the other end of the rear stator core body (8) is connected with the rear end heat dissipation frame feet (51);

The cooling water pipe (71) is a round copper water pipe. After passing through the cooling water pipe hole (74) of the middle frame bracket, the middle part of the copper water pipe is integrated with the middle frame bracket, and one end of the copper water pipe extends and embeds. In the arc-shaped cooling water pipe groove A (65) on the edge of the front stator core body (6), the other end of the copper water pipe is extended and embedded in the arc-shaped cooling water pipe groove B (85) on the edge of the rear rotor core body (8). ;

The middle part of the rotating shaft (3) is a cylindrical iron core body, and the cylindrical iron core body is provided with two embedded grooves (33). The rear end rotor core body protrusions (84) are respectively inserted into the two insert grooves (33) of the cylindrical core body, so as to closely form a rotor as a whole.

The cooling water pipe (71) has a water inlet pipe port (72) and a water outlet pipe port (73). The motor protrudes out, the water outlet port (73) extends out of the motor through the water outlet port slot (23) on the rear housing (2), and the water inlet port (72) is connected to an external variable frequency speed regulating pump.

The rotating shaft (3) is embedded with a front bearing (31) and a rear bearing (32), the front bearing (31) is embedded in a step in the front end housing (1) for fixing, and the rear bearing (32) is embedded in the rear end Fixed inside the steps in the housing (2).

The front-end wire wrap (61) and the rear-end wire wrap (81) are both made of oxygen-free enameled copper wire, and the conductivity of the oxygen-free enameled copper wire is 109.0% of that of electrolytic copper.

The front-end housing (1) is provided with a front-end wire outlet hole (11), and the rear-end housing (2) is provided with a rear-end wire outlet hole (21).

The front heat dissipation frame and the rear heat dissipation frame are made of aluminum alloy, and the middle frame support is made of heat-resistant engineering plastics.

During assembly, the front VMOS tube (93) is connected to the VMOS tube fixing hole C (43) by screws, and the rear VMOS tube (102) is connected to the VMOS tube fixing hole D (53) by screws.

technical effect

To sum up the above, the three-phase permanent magnet DC brushless motor for electric truck drive proposed by the present invention has the following beneficial effects:

In order to solve the power shortage caused by a single motor driving an electric truck, the present invention designs a new three-phase permanent magnet DC brushless motor with dual electromagnetic drive and dual electronic circuit drive, plus cooling water pipes. Topological structure adopts dual stator, dual rotor, single drive shaft, dual electronic circuit drive scheme, plus cooling water pipe heat dissipation structure and energy management multi-pronged approach, which can achieve high torque and high power output, highlighting the most economical system , the overall optimal characteristics.

In order to solve the problem of driving under high torque, the present invention designs a reasonable topology structure. By building a front-end heat dissipation frame, a back-end heat dissipation frame and a middle frame bracket to support the front-end PCB circuit board and the rear-end PCB circuit board, and then The synchronous double-push electronic drive is realized through the synchronous detection method, which solves the problem that the electric truck may be insufficiently driven by a single three-phase permanent magnet brushless motor. the problem of its increasing size.

In order to solve the problem of heat dissipation of the motor, a cooling water pipe is embedded in the stator of the three-phase permanent magnet brushless DC motor. In order to enhance the heat dissipation effect, the cooling water pipe is wound around the arc-shaped cooling water pipe groove A on the front stator iron core body and the rear stator iron core in turn. The arc-shaped cooling water pipe groove B on the body, the water pipe inlet port is connected to a variable frequency speed regulating water pump, and the cooling water flow can automatically adjust the pumping speed according to the internal temperature rise of the motor.

In order to prevent troubles before they occur, the present invention adopts an energy management chip in the driving structure for the possibility of overheating and spontaneous combustion caused by overcurrent during the operation of the motor.

In order to improve the fatigue resistance of the NdFeB permanent magnet material, the NdFeB permanent magnet material adopts a buried protection installation mode, and the front end permanent magnet and the rear end permanent magnet are all buried in the magnetic field of the front end rotor core body and the rear end rotor core body. In the steel groove, on the one hand, it can protect the fragile permanent magnet and reduce the influence of shear stress on it under high torque;

The invention carefully designs a novel rotor iron core structure. The middle part of the rotating shaft is provided with a cylindrical iron core body. During assembly, the cylindrical iron core body is inserted into the front rotor iron core body and the rear rotor iron core body respectively. Form a rotor as a whole, which greatly increases the moment of inertia of the rotating shaft.

A three-phase permanent magnet DC brushless motor for driving an electric truck designed by the invention has been proved by computer simulation that the topology is simple, the heat dissipation effect is good, and the output is strong, which truly overcomes the concerns of the users of the three-phase permanent magnet DC brushless motor. Iron boron permanent magnets may lose their magnetism or appear magnetic saturation in high temperature environments. More importantly, this is a three-phase permanent magnet brushless DC motor for electric truck drive based on energy management. It is at the forefront in overcoming the deflagration accident of electric vehicles, and its innovative significance is self-evident. In the past, people in the industry only knew that energy management was needed in terms of battery management (BMS), but they ignored that the three-phase permanent magnet brushless DC motor itself also needs energy management. The application prospect is quite broad.

It should be pointed out that innovation is the greatest free tool at the disposal of human beings. Since Faraday discovered the phenomenon of electromagnetic induction, the electric motor, which is only more than 150 years old, still has a broad space for development. Unfortunately, so far we have not found a cheap and high-quality alternative to the principle of electromagnetic induction. However, the three-phase permanent magnet brushless DC motor used for electric truck drives has taken a different approach. In terms of motor topology, electrical materials and electrical control Started a good innovation attempt.

The above specific embodiments are only exemplary. For well-known reasons, the Hall position sensor is not drawn in this embodiment, but those skilled in the art will understand that, without departing from the scope of the present invention defined by the appended claims Within the spirit and scope, various changes made to the present invention in terms of expansion of form and details, all belong to the protection scope of the present invention.

Claims (6)

1. The three-phase permanent magnet brushless DC motor for electric truck drive consists of front-end housing, rear-end housing, rotating shaft, front-end heat dissipation frame, middle frame bracket, rear heat dissipation frame, front-end PCB circuit board, rear-end PCB circuit board, It is composed of cooling water pipe, front-end stator core body, front-end wire package, front-end rotor core body, front-end permanent magnet, rear-end stator core body, rear-end wire package, rear-end rotor core body, and rear-end permanent magnet components. in: The three-phase permanent magnet DC brushless motor for driving an electric truck adopts a topology structure in which dual electromagnetic drives and dual electronic circuits are synchronously driven, plus cooling water pipes are combined into one. In the casing jointly surrounded by the casing, the rotating shaft protrudes from the central hole of the front end casing; The dual electromagnetic drive part includes a front-end stator core body, a front-end wire package, a front-end rotor core body, a front-end permanent magnet and a rear-end stator core body, a rear-end wire package, a rear-end rotor core body, and a rear-end permanent magnet. The front-end stator core body and the rear-end stator core body are made of cold-rolled silicon steel punching sheets superimposed. The edge of the front-end stator core body is provided with an arc-shaped cooling water pipe groove A, and the edge of the rear-end stator core body is opened. There is an arc cooling water pipe groove B; The front-end rotor core body and the rear-end rotor core body are both made of cold-rolled silicon steel punching sheets, and annular grooves are punched near the edges of the front-end rotor core body and the rear rotor core body. The front-end permanent magnets and the rear-end permanent magnets are made of NdFeB magnetic materials, sintered into concentric unequal-circle magnetic steel tiles, and then embedded in the annular grooves on the front-end rotor core body and the rear-end rotor core body respectively; The dual electronic circuit driving part includes a front-end PCB circuit board, a front-end heat dissipation frame and a rear-end PCB circuit board, and a rear-end heat dissipation frame. Cavity structure, the front heat dissipation frame protrudes from the front heat dissipation frame legs, and the rear heat dissipation frame protrudes from the rear heat dissipation frame legs; The front-end PCB circuit board has a hexagonal structure, and is welded with a front-end ARM chip, a front-end driver chip, a front-end VMOS tube, an energy management chip, a power three-terminal device, and a power inductor. At the fan-shaped boss of the front heat dissipation frame in the front heat dissipation frame; The back-end PCB circuit board is a hexagonal structure, on which the back-end ARM chip, the back-end VMOS tube, the back-end driver chip, the synchronous interlock chip, and the temperature sensor are welded, and then the back-end PCB circuit board is installed on the back-end to dissipate heat. At the fan-shaped boss of the rear heat dissipation frame in the frame; The front-end ARM chip and the back-end ARM chip communicate through their respective I/O ports, and then the I/O port of the back-end ARM chip controls the synchronous interlock chip to release the allow or prohibit command synchronously to control the front-end driver chip and the back-end. The driver chip, the front-end driver chip drives the front-end VMOS tube, and the back-end driver chip drives the back-end VMOS tube; The energy management chip on the front-end PCB circuit board can detect the U, V, W three-phase current signals, and the temperature sensor on the back-end PCB circuit board is used to detect the working environment temperature of the motor. When balanced and overheated, the synchronous interlock chip immediately releases the inhibit signal, and locks off the front-end VMOS tube and the back-end VMOS tube at the same time; The middle frame support is a ring with a hole in the middle, the edges of the ring respectively protrude the middle frame support legs, one end of the front stator iron core body is connected with the middle frame support legs, and the other end of the front end stator iron core body is connected. Connect with the front end of the heat dissipation frame, one end of the rear stator core body is connected with the middle frame support leg, and the other end of the rear stator core body is connected with the rear heat dissipation frame leg; The cooling water pipe is a round copper water pipe. After passing through the cooling water pipe hole of the middle frame bracket, the middle part of the copper water pipe is integrated with the middle frame bracket, and one end of the copper water pipe extends and is embedded in the edge of the front stator core body. In the arc-shaped cooling water pipe groove A, the other end of the copper water pipe is extended and embedded in the arc-shaped cooling water pipe groove B on the edge of the rear rotor core body; The middle part of the rotating shaft is a cylindrical iron core body, and there are two embedded grooves on the cylindrical iron core body. The cylindrical iron core body is embedded in two grooves to form a rotor as a whole; The cooling water pipe has a water inlet port and a water outlet port, the water inlet port passes through the water inlet port on the front shell and then extends out of the motor, and the water outlet port passes through the water outlet port on the rear shell to open. The groove extends to the outside of the motor, and the water inlet pipe is connected to an external frequency conversion speed-regulated water pump. 2. The three-phase permanent magnet DC brushless motor for driving an electric truck according to claim 1, wherein a front bearing and a rear bearing are embedded on the rotating shaft, and the front bearing is embedded in a step in the front end casing Fixed, the rear bearing is embedded in the step in the rear housing to be fixed. 3 . The three-phase permanent magnet DC brushless motor for driving an electric truck according to claim 1 , wherein the front-end wire wrap and the rear-end wire wrap both adopt oxygen-free enameled copper wire. 4 . 4. The three-phase permanent magnet DC brushless motor for driving an electric truck according to claim 1, characterized in that: the front-end housing is provided with a front-end outlet hole, and the rear-end housing is provided with a rear-end outlet hole. 5. The three-phase permanent magnet DC brushless motor for driving an electric truck according to claim 1, wherein the front heat dissipation frame and the rear heat dissipation frame are made of aluminum alloy, and the middle frame bracket is Heat-resistant engineering plastics. 6. The three-phase permanent magnet DC brushless motor for driving an electric truck according to claim 1, characterized in that: during assembly, the front-end VMOS tube is connected to the VMOS tube fixing hole C by screws, and the rear-end described The VMOS tube is connected to the fixing hole D of the VMOS tube through screws.

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