Electric vehicles are the development trend of the automobile industry. Everyone knows that the core of its principle is to replace the engine with a motor to achieve electric drive. Compared with conventional induction motors, electric vehicle motors are quite different in performance requirements and driving principles:

1. The electric vehicle motor should have a large starting torque, good starting performance and good acceleration performance to meet the requirements of frequent starting and stopping, acceleration and deceleration or climbing of electric vehicles. In motor testing, it is required that the response time of the motor should be short when speed or torque control is carried out; At the same time, when the external load changes step by step, the response of the motor itself should be fast enough to adjust the output power and speed;

2. The constant power range of motor of electric vehicle should be designed to be wide to meet the torque output of electric vehicle at high speed and ensure the high speed that the vehicle can achieve;

3. The motor of electric vehicle should have a wide range of speed regulation capability. It has a large torque at low speed and a high power at high speed. It can adjust the driving speed and corresponding driving force of electric vehicle at any time according to driving needs;

4. The electric vehicle motor should have good efficiency characteristics. It can obtain excellent efficiency within a wide speed/torque range. For the continuous driving mileage after raising the charge, it is generally required to obtain 85%~93% efficiency in the typical driving cycle area;

5. The overall dimension of electric vehicle motor shall be as small as possible, the weight shall be as light as possible, and the power density shall be optimized;

6. The electric vehicle motor should have good reliability, strong temperature resistance and humidity resistance, be able to work in a harsh environment for a long time, have low noise during operation, and be convenient for maintenance;

7. Whether the motor controller can effectively recover the energy generated by braking.

Brushed low-speed motor, no reducer gear device, simple structure, low cost, poor starting and uphill overload capacity, large power consumption. Because the speed of the brush high-speed motor is high (3000 rpm of the high-speed motor and 500 rpm of the low-speed motor), it needs to output large torque power after decelerating through the reduction gear device, so its noise is relatively higher than that of the low-speed motor. The production process of high-speed motor is more complex than that of low-speed motor, and the cost is high. The price is about 200 yuan expensive. For example, some famous brand electric vehicles use high-speed motor.