Estimation of state variables in induction motors with closed loop observers

The aim of this thesis is to estimate the state variables (stator currents, rotor fluxes) of a three phase squirrel-cage induction motor driven at constant speed for different supplies. Full-order and reduced-order observers are used for estimation. In observer design, the state-space model derived in the d-q axis domain of constant-speed induction motor is utilized. Estimation algorithms developed for either observer are programmed on MATLAB software environment.In the estimation algorithms, some results for different observer gain matrices are obtained from input/output data of the state-space simulation of induction motor supplied by sinusoidal and six-step voltage sources.It is shown that estimation results are quite consistent with the simulation results of induction motor.