Starter for AC motor

The utility model discloses a starting device of an alternating current motor, aiming to reduce the starting current at the time of starting a motor. The utility model adopts a technical scheme that the alternating current motor is driven to run at a preset speed by a starting motor, and then the alternating current motor is started; a machinery clutch method is adopted, which makes a rotor of the motor generate rotation in advance; the more the preset speed approaches to the rated speed of the motor, the more the preset speed approaches to the rated working current value of the motor, and the starting current of the motor is smaller. When a large motor is started by adopting the utility model, the starting current is small, which makes an electric network have small fluctuation and the large motor easy to be started, and the influence on other machines in operation is small, which is in favor of the stabilized production.