Which kinds of motors are commonly used in new energy vehicles? What are their strengths and weaknesses?

As the power source of new-energy vehicles, the quality of electric motor determines how far the new-energy vehicles can go. In addition, the development of electric vehicles in recent years is like the situation of "starting a prairie fire", the importance of electric motors is self-evident. At present, new energy vehicles on the market are mainly used by two types of motor, permanent magnet synchronous motor and AC asynchronous motor.

The principle of permanent magnet synchronous motor is electromagnetism. When the current is switched on, the coil in the motor generates a magnetic field, and because the magnets inside repel each other, the coil starts to rotate. The higher the current, the faster the coil rotates.

The advantage of permanent magnet synchronous motor is its small size and light weight, which can save a lot of space. In addition, PMSM has excellent performance in use efficiency. Its high power density enables the working efficiency of PMSM to reach 97%, which ensures the power and acceleration for the automobile. However, the disadvantage of PMSM is that it is expensive and requires the use of rare earths as materials. As we all know, China has the largest reserves of rare earths in the world, and the total production of magnetic materials in China has reached 80% of the world's total. Therefore, domestic electric vehicles are basically using permanent magnet synchronous motors, such as BaiC New Energy, BYD and Xiaopeng Automobile.

Although ac asynchronous motor can also be seen as the principle of electromagnetism, it is different from permanent magnet synchronous motor in that it adopts the design of coil + iron core. The magnetic field appears when the current is switched on, and the direction and magnitude of the magnetic field change as the current changes.

Although there is no high power of permanent magnet synchronous motor, the price of AC asynchronous motor is relatively low, so the cost control is ideal. However, large volume also takes up a certain amount of space of the car. In addition, high energy consumption is also a major drawback, resulting in low operating efficiency. Therefore, ac asynchronous motor is applied in new energy bus more. Tesla is also one of the car brands that mainly use AC asynchronous motors.

The development of motor is still in a bottleneck need to break the period, about the permanent magnet synchronous motor and ac asynchronous motor comparison, in fact, there is not much difference. Like domestic electric cars, they pay attention to space, while tesla, a joint venture brand, pursues more power. Therefore, the motors that focus on use are different.