Control strategies for three-phase asynchronous machines

This book presents an in-depth study of several speed sensorless control strategies for the asynchronous machine. Three main approaches are analyzed: rotor flux-oriented vector control (RFOC) direct torque and flux control (DTFC) and control based on the backstepping approach with integral action.Particular attention is paid to speed estimation using a fuzzy MRAS estimator recognized for its robustness. Speed control is then achieved using conventional PI and fuzzy PI controllers. To compensate for the sensitivity of performance to resistance variations two observers have been developed: a high-gain observer integrated into the RFOC strategy for rotor resistance estimation and a PI controller-based estimator integrated into the DTFC strategy for stator resistance estimation.This book is aimed at engineering students and PhD students specializing in electrical engineering.