Permanent magnet brushless motor control techniques

This paper reviews various techniques for controlling a permanent magnet DC brushless motor used for compressor. A number of driving methods have been considered. The 120 degrees commutation, sensor-less back EMF detection and the full control on the bridge three-phase inverter circuit techniques employed in the motor driving scheme are presented. Speed control of the system is achieved by PWM technique. PSIM software is used for the design of a prototype driver circuit. The control is successfully implemented by using a low cost microcontroller and IGBT module.