Microcontroller-based on-line self-tuning of the rotor time constant for field-oriented induction motor drives

A microcontroller-based online self-tuning of the rotor time constant for the field oriented control of an induction motor is presented, based on a power transfer method. The binary search approach to adaptation is considered, a method particularly suited for digital implementation with low-cost, fixed point devices. The robustness to discretization and quantization errors, the ease of the set-up and the inherent stability are the main characteristics of binary search. Simulation and experimental results confirm such a method as an interesting alternative to the standard-integrator solution