A determining method of flux level for deadbeat flux level controlled direct-field-oriented induction motors using adaptive flux observer

A method to determine the appropriate flux level corresponding to maximum efficiency of deadbeat flux level controlled direct-field-oriented induction motors has been proposed that employs an adaptive flux observer in consideration of change of parameters for operating conditions. Total losses in transient and steady states are required to be calculated in consideration of core loss from the equivalent circuit of an induction motor. By using deadbeat flux level control, this system can be applied to obtain quick response and high efficiency of the induction motor for a wide adjustable speed range. This paper describes the method as well as the fundamental characteristics of this system derived from experimental and simulation results