A Bridgeless Cuk Converter for Power Factor Correction and Speed Control in BLDC Motor

ABSTRACT: In this paper a bridgeless Cuk rectifier is used for Power factor correction (PFC) for a BLDC motor. Bridgeless Cuk converter has only two semiconductor switches in the current flowing path. During each interval of the switching cycle it result in less conduction losses and an improved thermal management compared to the conventional Cuk PFC rectifier. To achieve almost unity power factor and to reduce the input current stress, the topologies are designed to work in discontinuous conduction mode (DCM). The DCM hasadditional advantage such as zero-current turn-on in the power switches, zero current turn-off in the output diode.The ac-dc conversion of electric power is usually required for the BLDCM drive, it causes many current harmonics and results in poor power factor at input ac mains. This paper deals with power factor correction of BLDCM with bridgeless Cuk converter.A three phase voltage source inverter is used as an electronic commutator to operate BLDCM.