This paper deals with sensorless constant v/f closed
loop control of high-power induction motor with synchronized
space vector pulse width modulation (SVPWM). The rotor speed
is estimated based on the difference between the rotor flux speed
expressed in stationary reference frame and slip speed. The
estimated stator flux and the synchronous speed are used to
generate the estimated back EMF. The difference between the
reference voltage and the estimated back EMF voltage is used to
generate the stator resistance voltage drop compensation
required to maintain constant flux at low speed. Synchronized
SVPWM technique is used in this closed loop drive.
Synchronization guarantees elimination of sub-harmonics and
reduces low order frequency harmonics. Thus, the proposed
scheme guarantees high performance at high power levels. The
simulation and experimental results are presented.