CN111614206A

CN111614206A - Speed-regulating permanent magnet synchronous motor cooled by fan

Info

Publication number: CN111614206A
Application number: CN202010524598.XA
Authority: CN
Inventors: 薛周强; 曾学英; 战仁奎
Original assignee: Zhongda Motors Co Ltd
Current assignee: Zhongda Motors Co Ltd
Priority date: 2020-06-10
Filing date: 2020-06-10
Publication date: 2020-09-01

Abstract

The invention relates to a speed-regulating permanent magnet synchronous motor cooled by a fan, belonging to the technical field of motors. The fan comprises a front outer cover, a front end cover, a front inner cover, a machine base, a rotor, a rear inner cover, a rear end cover, a rear outer cover and a fan. The rotor comprises a rotating shaft, a rotor iron core, a screw, a pressing plate and magnetic steel, and the rotor iron core is connected with the rotating shaft in a matched manner; and magnetic steel is plugged into the rotor core, two ends of the magnetic steel are pressed tightly by using the pressing plate, the screw penetrates through the pressing plate and the rotor core, and the screw, the pressing plate and the rotor core are connected by using the nut. According to the invention, the main structure of the motor is changed by adjusting the connection mode of the fan of the permanent magnet motor, and the operation range of the motor is enlarged. The permanent magnet synchronous motor can greatly improve the efficiency of the motor, improve the cooling effect of the motor, reduce the temperature of the motor in the operation process, enlarge the operation range of the motor and better play the characteristic of high efficiency of the permanent magnet motor on the basis of saving materials.

Description

Speed-regulating permanent magnet synchronous motor cooled by fan

Technical Field

The invention relates to a speed-regulating permanent magnet synchronous motor cooled by a fan, belonging to the technical field of motors.

Background

Compared with a direct current motor, the permanent magnet synchronous motor has no defects of a commutator, an electric brush and the like of the direct current motor. Compared with an asynchronous motor, the asynchronous motor does not need reactive exciting current, so that the efficiency is high, the power factor is high, the moment-inertia ratio is large, the loss of stator current and stator resistance is reduced, the rotor parameter can be measured, and the control performance is good; however, compared with an asynchronous motor, the motor has the difficulties of high cost, difficult starting and the like.

Since the magnetic field of the permanent magnet synchronous motor is generated by the permanent magnet, the excitation loss (copper loss) caused by the generation of the magnetic field by the excitation current is avoided.

Compared with an asynchronous motor, the external characteristic efficiency curve of the permanent magnet synchronous motor has a much higher value under light load, which is the greatest advantage of the permanent magnet synchronous motor in energy conservation compared with the asynchronous motor. Because normally the motor is driving a load, it is rarely the case to run at full power, because: on one hand, when the motor is in a model selection mode, a user generally determines the power of the motor according to the limit working condition of the load, the probability of the limit working condition is low, and meanwhile, in order to prevent the motor from being burnt in the abnormal working condition, the user can further reserve allowance for the power of the motor; on the other hand, when a designer designs a motor, in order to ensure the reliability of the motor, a certain power margin is further reserved on the basis of the power required by a user, so that more than 90% of the motor actually operated is operated below 70% of the rated power. The permanent magnet synchronous motor can still keep higher efficiency in a light load area, and the efficiency of the permanent magnet synchronous motor is more than 20% higher than that of an asynchronous motor.

China is becoming one of the largest production bases of motors and motor system components all over the world, but the energy-saving condition of the motors in China is not optimistic. The average value of the efficiency of the YE2 series motors widely applied at home at present is 90.08 percent; and the average efficiency of the international ultra-high efficiency motor (IE 4) is 93.3%. Therefore, the improvement of the energy efficiency of the motor system produced in China is not only beneficial to China economy, but also beneficial to sustainable energy supply of international markets.

As shown in fig. 1, a permanent magnet synchronous motor in the prior art is formed by connecting a front outer cover 1, a front end cover 2 and a front inner cover 3 through bolts, connecting the front end cover 2 and a base 4 through bolts, connecting the base 4 and a rear end cover 7 through bolts, connecting a rear inner cover 6, a rear end cover 7 and a rear outer cover 8 through bolts, mounting a rotor 5 on the motor through a bearing, mounting a fan 9 on the rotor, and mounting a fan cover on the rear end cover 8 through bolts.

In the prior art, the permanent magnet motor uses a coaxial fan, the fan rotates at the same speed when the motor rotates, but according to the actual working conditions used at present, the permanent magnet motor needs to operate at a speed regulation range which generally reaches 0-3600 revolutions, when the coaxial fan is used, the rotating speed of the fan is slowed down when the permanent magnet motor rotates at a low rotating speed, the air volume of the fan is reduced after the fan is slowed down, and the motor cannot obtain a good cooling effect. Currently, permanent magnet machines are designed with efficiencies equal to or higher than those of international ultra-efficient motors (IE 4). Therefore, the permanent magnet motor is reasonably and effectively designed, and the characteristic of high efficiency of the permanent magnet motor is better exerted on the basis of saving materials.

Disclosure of Invention

The invention aims to overcome the defects and provide the speed-regulating permanent magnet synchronous motor cooled by the fan, which can greatly improve the efficiency, reduce the temperature of the motor in the operation process and enlarge the operation range.

According to the technical scheme provided by the invention, the speed-regulating permanent magnet synchronous motor cooled by the fan comprises a front outer cover, a front end cover, a front inner cover, a base, a rotor, a rear inner cover, a rear end cover, a rear outer cover and the fan; the front outer cover and the front inner cover are respectively arranged on two sides of the front end cover, and the front outer cover, the front end cover and the front inner cover are sequentially connected through bolts; one side of the engine base is connected with the front end cover, and the other side of the engine base is connected with the rear end cover; the rear inner cover and the rear outer cover are respectively arranged on two sides of the rear end cover, and the rear inner cover, the rear end cover and the rear outer cover are sequentially connected through bolts; the rotor is connected with the front end cover and the front end cover in a matched mode through a bearing.

Furthermore, the rotor comprises a rotating shaft, a rotor iron core, a screw rod, a pressing plate and magnetic steel, wherein the rotor iron core is connected with the rotating shaft in a matched manner; and magnetic steel is plugged into the rotor core, two ends of the magnetic steel are pressed tightly by using the pressing plate, the screw penetrates through the pressing plate and the rotor core, and the screw, the pressing plate and the rotor core are connected by using the nut.

Further, the engine base is connected with the front end cover and the rear end cover through bolts.

The invention has the beneficial effects that: according to the invention, the main structure of the motor is changed by adjusting the connection mode of the fan of the permanent magnet motor, and the operation range of the motor is enlarged. The permanent magnet synchronous motor can greatly improve the efficiency of the motor, reduce the temperature of the motor in the operation process and enlarge the operation range of the motor.

Drawings

Fig. 1 is a schematic structural diagram of a conventional permanent magnet synchronous motor.

Fig. 2 is a schematic structural diagram of the present invention.

Fig. 3 is a schematic view of the rotor structure of the present invention.

Description of reference numerals: 1. a front outer cover; 2. a front end cover; 3. a front inner cover; 4. a machine base; 5. a rotor; 6. a rear inner cover; 7. a rear end cap; 8. a rear outer cover; 9. a fan; 10. A fan.

Detailed Description

As shown in fig. 2, a fan-cooled speed-regulating permanent magnet synchronous motor comprises a front outer cover 1, a front end cover 2, a front inner cover 3, a base 4, a rotor 5, a rear inner cover 6, a rear end cover 7, a rear outer cover 8, a fan 10, a rotating shaft 5-1, a rotor core 5-2, a screw rod 5-3, a pressure plate 5-4, magnetic steel 5-5 and the like.

The front outer cover 1 and the front inner cover 3 are respectively arranged on two sides of the front end cover 2, and the front outer cover 1, the front end cover 2 and the front inner cover 3 are sequentially connected through bolts; one side of the base 4 is connected with the front end cover 2, and the other side of the base is connected with the rear end cover 7; the rear inner cover 6 and the rear outer cover 8 are respectively arranged at two sides of the rear end cover 7, and the rear inner cover 6, the rear end cover 7 and the rear outer cover 8 are sequentially connected through bolts; the rotor 5 is connected with the front end cover 2 in a matching way through a bearing.

The rotor 5 comprises a rotating shaft 5-1, a rotor iron core 5-2, a screw 5-3, a pressing plate 5-4 and magnetic steel 5-5, wherein the rotor iron core 5-2 is heated to 200 ℃ and is connected with the rotating shaft 5-1 in a hot sleeve matching manner; magnetic steel 5-5 is plugged into rotor core 5-2, two ends of pressing plate 5-4 are used for pressing, screw rod 5-3 penetrates pressing plate 5-4 and rotor core 5-2, and screw rod 5-3, pressing plate 5-4 and rotor core 5-2 are connected through nut.

The engine base 4 is connected with the front end cover 2 and the rear end cover 7 through bolts. The fan 10 is connected with the rear end cover 7 through bolts.

The fan cools the permanent magnet motor, the fan is separated from the motor, when the motor runs at a low rotating speed, the rotating speed of the fan cannot be changed, and meanwhile, the fan can provide lasting and unchangeable air volume. The temperature of the motor does not change with the change of the rotating speed. The permanent magnet synchronous motor can greatly improve the efficiency of the motor, reduce the temperature of the motor in the operation process, enlarge the operation range of the motor and improve the cooling effect of the motor. Therefore, the permanent magnet motor is reasonably and effectively designed, and the characteristic of high efficiency of the permanent magnet motor can be better played on the basis of saving materials.

Claims

1. A speed regulation permanent magnet synchronous motor using a fan for cooling is characterized in that: comprises a front outer cover (1), a front end cover (2), a front inner cover (3), a machine base (4), a rotor (5), a rear inner cover (6), a rear end cover (7), a rear outer cover (8) and a fan (10);

the front outer cover (1) and the front inner cover (3) are respectively arranged on two sides of the front end cover (2), and the front outer cover (1), the front end cover (2) and the front inner cover (3) are sequentially connected through bolts; one side of the machine base (4) is connected with the front end cover (2), and the other side of the machine base is connected with the rear end cover (7); the rear inner cover (6) and the rear outer cover (8) are respectively arranged at two sides of the rear end cover (7), and the rear inner cover (6), the rear end cover (7) and the rear outer cover (8) are sequentially connected through bolts; the rotor (5) is connected with the front end cover (2) in a matching way through a bearing; the fan (10) is connected with the rear end cover (7);

the rotor (5) comprises a rotating shaft (5-1), a rotor iron core (5-2), a screw (5-3), a pressing plate (5-4) and magnetic steel (5-4), wherein the rotor iron core (5-2) is connected with the rotating shaft (5-1) in a hot-sleeved fit manner; the magnetic steel (5-5) is plugged into the rotor core (5-2), two ends of the magnetic steel are pressed tightly by using the pressing plate (5-4), the screw (5-3) penetrates through the pressing plate (5-4) and the rotor core (5-2), and the screw (5-3), the pressing plate (5-4) and the rotor core (5-2) are connected by using the nut.

2. The fan-cooled speed-regulating permanent magnet synchronous motor according to claim 1, wherein: the engine base (4) is connected with the front end cover (2) and the rear end cover (7) through bolts.