Study of a New Rotor Flux Estimator for Induction Machine Based on Sliding Mode Control

A new rotor flux linkage estimator based on sliding mode control (SMC) is proposed for vector controlled induction machine (IM) to improve the performance of the flux orientation and torque control for IM. The stator current and rotor flux sliding mode estimators were constructed in stator coordinate frame. Furthermore, the adjusting parameters for SMC are optimized to improve the estimation accuracy and the choosing principle is given in the paper. Meanwhile, the stability of the SMC flux estimator is also analyzed, which verifies that the new estimator has excellent disturbance resistance to motor parameters change. The experiments show that the presented flux observer is able to deliver accurate estimation in both steady and transient state.