Modelling and Simulation of Cost Effective Sensorless Drive for Brushless DC Motor

Abstract

This paper deals with a new commutation approach to achieve the sensorless drive of permanent magnet BLDC motor over the conventional six switch commutation circuitry. In the simulation model, we have introduced four switch three phase Brushless DC (BLDC) motor drive in which the rotor position is estimated using back EMF detection technique. In sensorless concept, the electronic commutation circuit plays an important role to drive motors because of their non-self commutating nature. In this work, power electronics based inverter along with logical circuitry has been employed in order to perk up the sensorless technique of BLDC motor. This driving procedure is always advantageous over sensored drives of BLDC motors, which come with bulky module using Hall-effect position sensors to detect the rotor position. Thus, this sensorless performance not only reducing the hardware complexity but also minimizes the consumption of power by associated circuitry. The effectiveness of the design is demonstrated through simulation results. The performance of this design is first evaluated by MATLAB based SIMULINK platform which gives a satisfactory result. Finally, this study helps us to develop a real time implementation of cost effective drive without hall sensors for BLDC motor.