Pl. Jansen et Rd. Lorenz, TRANSDUCERLESS FIELD ORIENTATION CONCEPTS EMPLOYING SATURATION-INDUCED SALIENCIES IN INDUCTION MACHINES, IEEE transactions on industry applications, 32(6), 1996, pp. 1380-1393
This paper explores the tracking of high-frequency magnetic saliencies
created by saturation as a means of continuously estimating the posit
ion and magnitude of flux for transducerless field oriented control at
zero and low frequency operation, Tracking is based upon inverter-gen
erated high-frequency signal injection with demodulation incorporating
heterodyning and a closed-loop tracking filter, Integration of the tr
acking scheme with the voltage model in a closed-loop flux observer to
pology is proposed as an attractive means of achieving very wide speed
range transducerless field oriented control, The focus is toward indu
ction machines, although the applicability to surface-mounted permanen
t magnet synchronous machines is also briefly discussed, Experimental
evaluation of saturation effects in two induction machines is included
, as well as simulation results demonstrating sustained torque control
at zero fundamental frequency.