AC motor power supply
AC motors generally use three-phase system, because three-phase AC motors have obvious advantages in terms of performance indicators, raw material utilization and price compared with single-phase motors. A three-phase motor of the same power is smaller, lighter, and less expensive than a single-phase motor. The three-phase motor has a self-starting capability. Single-phase motors do not have starting torque. To solve the starting problem, special measures must be taken. The torque of a single-phase motor is pulsating and the noise is relatively large, but the required power supply is relatively simple, especially in the home. Therefore, single-phase motors are often used for small household motors and instrument motors.