A PFC based switched-capacitor buck-boost converter fed BLDC motor drive

A PFC (Power Factor Correction) based singlestage, single-switch SC (Switched-Capacitor) buck-boost converter is proposed to feed BLDC (Brushless DC) motor drive. The speed of proposed drive is controlled by varying the DC link voltage of VSI (Voltage Source Inverter) feeding BLDC motor. Moreover, the BLDC motor is electronically commutated which has reduced switching losses in VSI. The SC buck-boost converter is designed to operate in DICM (Discontinuous Inductor Current Mode) to act as an inherent power factor corrector. A reduced sensor configuration of a BLDC motor is developed to realize a cost effective solution for low power household applications. The proposed drive is designed for speed control over a wide range with nearly unity power factor.