Losses minimisation in an induction motor

the present work is a contribution to improve efficiency and the robustness of a indirect field oriented of induction motor drives. The efficiency of the motor deteriorates for two reasons: The variation of rotor resistance and operation under light loads, with a constant field. For these reasons, a method is proposed to choose the optimal field to minimize total machine losses. On the other hand, to avoid the problem of rotor resistance variation, a mechanism based on the fuzzy logic is proposed to maintain the decoupling and avoid supplementary losses. An extensive simulation works yields to selected results to highlight the efficiency of proposed methods.