Speed control of BLDC motor with Four Switch Three Phase Inverter using Digital Signal Controller

The main purpose of this paper is to develop a low cost drive system for BLDC motor with reduced switches and minimum hardware. Due to the characteristics of the Brushless DC motor such as high efficiency, hig h power factor, high torque, low maintenance and ease of control, it is widely used in variable speed drives and industrial applications. The flexibility of the drive system can be increased by using dsPIC Digital Signal Controller which combines the features of Microcontroller and Digital Signal Processor on a single chip. The BLDC motor is excited by a Four Switch Three Phase Inverter with minimum number of switches which in turn reduce the associated amount of switching losses. It results in low electromagnetic interference, less complexity of control and reduced interference circuits. A simulation is carried out using MATLAB/SIMULI NK and in the experimental work, a prototype model of hardware is developed.