An Analysis of an Adjustable Speed PFC BL-SEPIC and ZETA Converter Fed PMBLDCM

This paper presents an analysis of speed control of a permanent magnet brushless DC motor (PMBLDCM) by using Bridgeless Single Ended Primary Inductor Convertor (BLSEPIC) and ZETA converter. A SEPIC converter is buck converter followed by buck-boost converter and ZETA converter is basically buck-boost converter. The proposed schemes combine the PFC and DC link voltage control at one stage. A DC link voltage is control to achieve better speed control of PMBLDCM. A controlled DC link voltage is proportional to desired speed of PMBLDCM. The proposed schemes are design to achieve power factor near to unity. Current multiplier approach is used in proposed scheme. A power factor correction (PFC) controller is designed in discontinuous Current Mode (DCM).A rate limiter is used for control torque and current in PMBLDCM at DC link. Conduction losses are less due to implementation of this scheme. The proposed PFC convertor provides better power quality at input AC mains. From the various results obtained after simulation of BL-SEPIC as well as ZETA converter different parameters also explain. BL-SEPIC gives better speed control of PMBLDCM as compare to ZETA converter. The proposed schemes are designed and results are shown in Matlab Simulink Environment.