A new integration algorithm for flux estimation using the voltage model

Vector control has very good transient and steady-state performance in induction motors. Furthermore, most direct stator flux orientation methods do not need speed information and these methods are not sensitive to parameters other than stator resistance. However, the performance of these control strategies depends on accurate estimation of the stator flux. The voltage model is one of the methods used for estimating the stator flux. In this paper, we discuss the integration methods for the voltage model which have an open integration problem, and those which have magnitude and angle errors in the stator flux. We then describe a new compensator to solve the problems associated with the integrator. The limiting level in the feedback loop of this compensator is estimated by using the intersection points of the two phases of the stator flux. The proposed new compensation method, which is computationally fast, has been both simulated and implemented on an experimental system. Experimental results show excellent performance, especially near zero speed.