First, ordinary motors can only work for a long time near the power frequency, while variable frequency motors can work for a long time under severe conditions, or below the power frequency; for example, the power frequency in our country is 50Hz. If the ordinary motor is in a condition of 5Hz or 2000Hz for a long time, it will soon appear faulty or even be damaged; and the occurrence of the frequency conversion motor will solve the problem of the ordinary motor.
Second, the cooling systems of ordinary motors and variable-frequency motors are different. The cooling systems and speeds of ordinary motors are closely related. Or, the speed of motors is fast, the cooling system is effective, the motor speed is slow, and the cooling effect is greatly reduced. Inverter motors do not have this problem.