Control of induction motors for both high dynamic performance and high power efficiency

An attempt to control induction motors with high dynamic performance and maximal power efficiency by means of decoupling of motor speed (or motor torque) and rotor flux is discussed. For maximal power efficiency, the squared rotor flux is adjusted according to the Fibonacci search method until the measured power input reaches the minimum. Since the motor speed is dynamically decoupled from the rotor flux, this can be done successfully without any degradation of motor speed responses. Furthermore, the performance of the control scheme is robust with respect to variations in rotor resistance because an identification algorithm for rotor resistance is used