Research on a Novel Motor Flux Observer Based on Voltaje Model

Motor stator flux linkage observer is important in the direct torque control which used to estimate the torque and to determine the voltage vector. The most ways of stator flux observer is based on motor voltage model to avoid the variation of the motor induction parameter which is caused by saturation. Classic strategy of flux observer is to get the flux by integrating the voltage, and the common problem is delay and drift with DC error. This paper makes a farther study on stator flux observer based on PLL which can avoid the delay and drift. A small-signal model of the observer is first established and then the translation function is yielded. The optimal parameter of the observer is selected by the automatic control theory; simulation and experiment validate the small signal model and the choice of the parameter