Bridgeless PFC Converter for SMPS & BLDC Drive Applications

Abstract

The devices generally used in industrial, commercial and residential applications need to undergo rectification for their proper functioning and operation.  Hence there is a need to reduce the line current harmonics so as to improve the power factor of the system. This has led to designing of Power Factor Correction circuits. This concept presents a power factor corrected (PFC) bridgeless (BL) buck–boost converter-fed SMPS. The brushless DC (BLDC) motor is becoming increasingly popular in sectors such as automotive (particularly electric vehicles (EV)), HVAC, white goods and industrial because it does away with the mechanical commutator used in traditional motors, replacing it with an electronic device that improves the reliability and durability of the unit. Because a BLDC motor dispenses with the brushes – instead employing an “electronic commutator” – the motor’s reliability and efficiency is improved by eliminating this source of wear and power loss. In addition, BLDC motors boast a number of other advantages over brush DC motors and induction motors, including better speed versus torque characteristics; faster dynamic response; noiseless operation; and higher speed ranges. This paper deals with the design, analysis, simulation, and development of a power-factor-correction (PFC) multiple output switched-mode power supply (SMPS) using a bridgeless buck–boost converter at the front end. Single-phase ac supply is fed to a pair of back-to-back-connected buck–boost converters to eliminate the diode bridge rectifier, which results in reduction of conduction losses and power quality improvement at the front end. The performance of the proposed multiple-output SMPS is evaluated under varying input voltages and loads by simulating this circuit in MATLAB/Simulink environment.