Electrolytic Capacitor-Less Single-Phase to Three-Phase Inverter with Harmonics Suppression Control for Air Conditioner

Global demand for highly energy-efficient inverter air conditioners is rising. However, the power converter must comply with harmonics regulations. This requires the converter to have a large inductor, PFC circuit and electrolytic capacitor. Therefore, the converter becomes expensive, which prevents inverter air conditioners from becoming popular around the world. In order to solve this problem, electrolytic-capacitor-less inverters were proposed. This paper proposes a harmonics suppression control of an electrolytic capacitor-less inverter. As a result of applying this control, the inductance and the capacitance of power converter have been reduced to 1/6 and 1/50, respectively, compared with those for conventional power converters, which has resulted in the commercialization of low-cost inverter air conditioners.