A brushless DC motor drive with power factor correction using isolated zeta converter

Abstract

This paper presents a brushless dc (BLDC) motor drive with power factor correction (PFC) for low-power applications. In this work, the speed of the BLDC motor is controlled by adjusting the dc link voltage of the voltage source inverter (VSI) feeding a BLDC motor. Therefore, VSI is used for achieving only an electronic commutation of the BLDC motor and operates in a low frequency switching for reduced switching losses. A PFC-based isolated zeta converter operating in discontinuous conduction mode (DCM) is used for controlling the dc link voltage of the VSI with inherent PFC at ac mains using single voltage sensor. The proposed drive is implemented to achieve a unity power factor at ac mains for a wide range of speed control and supply voltage fluctuations. An improved power quality is achieved with power quality indices within limits of IEC 61000-3-2 standard.