The reason for the wholesale of synchronous motors is that synchronous motors have the following advantages:
1. The rotor has no excitation winding, so there is no rotor copper loss, so the efficiency is high;
2. High performance permanent magnet materials provide excitation, and the given power is small, so the volume can be reduced;
3, the rotor inertia is small, so the dynamic performance is good;
4. High power and torque output at low efficiency.
However, it is unavoidable to have disadvantages, such as high cost, low reliability, complex processing technology, poor mechanical strength, and the performance of electric vehicles is greatly affected by the environment.The synchronous motor can adjust the power factor flexibly by excitation.The power factor of asynchronous motor can not be adjusted, so in some large factories, asynchronous motor application more, can be attached to a synchronous motor for adjusting camera, used to adjust the factory and the power factor at the grid interface.However, because of the high cost of synchronous motor, maintenance work is large, now generally use capacitor compensation power factor.
Because the synchronous machine has excitation winding and slip ring, the operator needs to have a higher level to control the excitation. In addition, compared with the non-maintenance of asynchronous motor, the maintenance workload is larger.Therefore, as a motor, now most of the choice of asynchronous motor.
