A Variable Speed BLDC Motor Drive Fed from A PFC Based Bridgeless Synchronous Buck Boost Converter

Abstract: A power factor correction (PFC) based Synchronous buck- boost converter fed brushless DC motor drive and an economic solution for low power applications is presented in this paper. A voltage source inverter which comprises low switching losses is fed from the dc link voltage is used to control the speed of BLDC motor. The dc link voltage is controlled by a synchronous buck boost converter which receives power from a diode bridge rectifier unit. Analysis of PFC synchronous buck- boost converter is made and its performance was assessed under continuous and discontinuous modes of operation. A BLDC motor is well known for its low maintenance, good efficiency and higher price. So reducing the cost of the BLDC motor has become essential. Pulse Width Modulation (PWM) technique has been broadly used to control power converter circuits. The results reveals that the harmonics in the output voltage and current has been reduced compare to buck boost converter.

Keywords: Synchronous buck- boost converter, power factor correction (PFC), Brushless DC motor, Pulse Width Modulation (PWM).