Green Power GPST series full-automatic AC voltage regulator collects sample and amplifies it and automatically control circuit, and drives the servomotor to rotate the rocker arm and brush in required direction, and finally adjusts the output voltage to the rated value, finally reaches the aim of stabilizing the voltage. It can be widely used in areas, where the mains voltage often comes across sharp fluctuation or sharp seasonal variation, such as industrial production, scientific research, medical treatment & hygiene, household electrical appliances, it can provide any loads with excellent power supply.