DSP-based minmax speed sensorless induction meter drive with sliding mode model-following speed controller

A speed sensorless induction motor (IM) drive with a sliding mode model-fol lowing speed controller is introduced. First, the speed estimation algorith m, based on the minmax control theory, and its stability analysis are descr ibed. An integral-proportional (IP) speed controller using the estimated sp eed signal is designed to obtain the desired control performance of command tracking. Moreover, to increase the robustness of the IM drive, a sliding mode model-following controller is added, where the state-space equation of the nominal designed IP speed control loop is selected as the reference mo del. To increase the accuracy of the estimator, the speed estimation algori thm is implemented using a digital signal processor.