Comparative study of three different bridge-less converters for reduction of harmonic distortion in brushless DC motor

Abstract

<p>This paper represents a comparative study of three different types of DC-DC<br />converter that can be used for reduction of Total Harmonic Distortion (THD)<br />in stator current, back electromotive force (EMF) and torque of brush less<br />DC motor. In addition, the topologies of these converters are analysed, and<br />the THD of the output characteristics have also been studied. In this work,<br />SEPIC, Zeta and Flyback converters are considered and their outputs are fed<br />to the BLDCM with the help of universal bridge or six step inverter.<br />Moreover the THD of the output voltages are not only measured for three<br />converters but also reduced by tuning the parameters. At first these three<br />converters are modeled in MATLAB/ Simulink based simulation platform<br />and studied the performance individually and further executed with hardware<br />circuitry. Finally the output parameters from both software simulation and<br />real time hardware are compared for these three converters separately and got<br />satisfactory similar results. Again we studied the performance with these<br />converters in terms of efficiency while fed in the commutation drive circuitry<br />of BLDCM by considering minimum THD. From this comparative<br />simulation results, it has been observed that Zeta converter showed maximum<br />efficiency. Therefore, in real time hardware implementation, the<br />commutation drive circuitry of BLDCM is studied with Zeta converter. With<br />this configuration, a comparatively low THD of stator current, back EMF and<br />electromagnetic torque have been achieved in BLDCM with PID controller.</p>