Permanent magnet brushless DC (PMBLDC) motors are the latest choice of researchers due to their high efficiency,
silent operation, compact size, high reliability and low maintenance requirements. These motors are preferred for
numerous applications; however, most of them require sensorless control of these motors. The operation of PMBLDC
motors requires rotor-position sensing for controlling the winding currents. The sensorless control would need estimation
of rotor position from the voltage and current signals, which are easily sensed. This paper presents state of the art
PMBLDC motor drives with an emphasis on sensorless control of these motors.