Improved power quality PMBLDC motor drive for constant speed variable torque load using non-isolated SEPIC converter

This paper presents an improved power quality permanent magnet brushless DC motor (PMBLDCM) drive for constant speed variable torque loads e.g. people/luggage carrier belts in airport lobbies, conveyor belts in industries etc. A non-isolated single-ended primary inductor converter (SEPIC) is used for power factor correction (PFC) and operated under current multiplier control. SEPIC converter is used to regulate the DC link voltage and also to ensure improved power quality (PQ) at AC mains. The proposed drive is designed and modeled for a PMBLDC motor rated at 1.07 KW, 4600 rpm, 350 volts and 2.2 Nm. Its performance is simulated in MATLAB/Simulink environment for constant speed and variable torque load as well as varying input voltage conditions. The simulated results demonstrate improved power quality at AC mains of the proposed drive along with the desired speed and torque control under varying load and voltage conditions.