As the power source of electric vehicles, the importance of electric motors is self-evident. At present, most domestic electric vehicles adopt permanent magnet synchronous motors with low power consumption but high manufacturing cost, such as BYD, BAIC New Energy, Geely Emgrand, etc;
Of course, there are also a few models that use AC asynchronous motors with lower cost but more electricity consumption, such as Weilai ES8 and Jiangling e200.
This time, we will discuss the types of motors used by mainstream domestic brands and the recommendations of related models.
When it comes to permanent magnet synchronous motor, we have to mention the four-wheel drive motor played when we were young. Due to the principle of electromagnetism, the coil in the motor will generate a magnetic field after being electrified, at the same time, it starts to rotate with the internal magnet due to the same pole Repulsion. At this time, the increase of current drives the rotation speed of the coil.
Different from the design of permanent magnet synchronous motor using magnet coil, AC asynchronous motor uses coil core design, although the principle of electromagnetism is also adopted, however, compared with permanent magnet synchronous motor, which only needs to energize the coil, AC asynchronous motor needs to energize the coil and iron core at the same time.
After the magnetic field appears, with the change of alternating current, the direction and size of the magnetic field are also constantly changing. At this time, the coil begins to cut in the magnetic field and induce current at the same time.
At present, most domestic manufacturers like to use permanent magnet synchronous motors in the use of electric vehicles, but most European and American companies will choose AC induction motors for the following reasons: 1.
European and American manufacturers initially made electric cars mainly for electric sports cars, which required larger torque to achieve high acceleration. With the progress of technology, although permanent magnet synchronous motors have emerged and are more efficient, however, it is obviously impossible for European and American manufacturers to give up the mature induction motor technology and turn to the research and development of induction synchronous motors. The reason why domestic manufacturers use permanent magnet synchronous motors is also related to market environment factors. 2.
Put aside the market and technical factors, the rare earth materials used in permanent magnet synchronous motors are relatively rare overseas. According to the data, China currently has about 70% of the world's rare earth resources, moreover, the total output of NdFeB magnetic materials, the main raw material of permanent magnets, has reached 80% of the world's total. Under such circumstances, China will not be surprised that permanent magnet synchronous motors are the main ones.
Regarding the advantages and disadvantages of these two types of motors, the following table makes a summary: at present, the new energy brands using induction motors in China are mainly Weilai, among them, ES8 continues the previously released electric sports car with the design of asynchronous induction motor. The design of front and rear double motors can bring a maximum power of 478kW, and thus bring 4.
4 seconds of 100 kilometers acceleration, and the motor supplier is the power of their own.
Different from the design of ES8 full asynchronous induction motor, although the ES6, Weilai's second mass production model, adopts the design of double permanent magnet synchronous motor in the benchmark version, however, its performance version adopts the combination of asynchronous induction motor and permanent magnet synchronous motor. Its front axle is equipped with 160kW permanent magnet synchronous motor and its rear axle is equipped with 240kW asynchronous induction motor, this combination allows the ES6 not only to have a longer range, but also high performance.
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