The brushless dc motor is synchronous motor, means magnetic field generated by rotor and stator rotate at same speed. It is consist of stator in the form of poly phase armature winding and rotor in the form of permanent magnet. As name suggest, brushless dc motor does not have brushes for commutation as in case of brushed motors. The process of commutation in brushless dc motor is carried out with use of semiconductor switches. These switches are used to turn on and off the stator winding at appropriate time interval, since this process is often called as electronic commutation. The brushless dc motor is constructed in two types, in first case placement of winding is in core and rotor is outside, hence rotor magnet act as insulator and help to reduce rate of heat dissipation. It operate at low current therefore generally used in fans. In second type, winding is outside the core hence dissipate more heat consequently help in to increase its torque, it is typically used in ha...