Transition and Latest Technology of Power Electronics for Air Conditioners

40 years has pasted since the first inverter air conditioner was commercialized. With the advent of inverter air conditioners, the comfort and energy-saving performance of air conditioners have significantly improved over the past 40 years. Today, the global demand for energy is increasing year by year, and the importance of energy conservation is increasing. Under these circumstances, inverter air conditioners are rapidly widespread around the world. This paper describes the transition of energy-saving performance of air conditioners from the view of inverters and motors, and finally, control method, issues, and efficiency improvement effects of an open-end-winding motor and a dual inverter drive system are explained as an example of latest technologies applied in air conditioners.