In high performance applications like servos to traction
drives BLDC motor drives are used extensively rather than
permanent magnet synchronous motor (PMSM). BLDC
motor possesses high efficiency, high power density, high
torque to inertia ratio and simple in control compared to
PMSM. In applications like silicon wafer manufacturing,
medical, robotics and automation induatries to the military
high precision control is required and this can be achievable
with the help of ripple free torque control[1]. BLDCs
achieve commutation electronically by incorporating a
feedback from the rotor-position into a control system
instead of mechanical commutators found in brushed dc
motors. Such a controller excites the stator coils of the
motor in a specific order to rotate the magnetic field
generated by the coils to be followed along by the rotor. In