Fuzzy robust speed controller for detuned field-orientated induction motor drive

Abstract

The speed control performance improvement of a detuned indirect field-oriented (IFO) induction motor drive is studied. First, the dynamic behaviour of a detuned IFO induction motor drive is observed, and its transfer function model is established. Then a proportional plus integral-derivative (PID) two-degree-of-freedom controller (2DOFC) is designed for an ideal IFO induction motor drive for a nominal case with the desired dynamic response. As the variation of motor parameters occurs, the detuning of field-orientation accompanying the load parameter changes may significantly worsen the speed dynamic response. In this case, a compensation signal is yielded by a proposed fuzzy robust controller (FRC) in order to preserve the prescribed response. Since the compensation signal is adaptively tuned by a model following the error driven fuzzy weighting controller, and moreover, the compromise between control effort and performance is considered, the robust model following speed response is obtained. Effectiveness of the proposed controller is verified by simulation and by measured results.