Cross and dot product based MRAS Observer of the rotor position of doubly fed induction machine

The paper presents a new type of rotor position observer using cross and dot products of the estimated and measured rotor current vector. A novel synchronization error function contains modified function atan2 and the vector products. The modification of error function is aimed at making the function monotonic, what provides faster response of the observer. Two rotor speed and position observers with the modified error function are presented. The former is based on the flux model of doubly fed induction machine DFIM and can be made in both αβ and dq frames, whereas the latter is based on the voltage steady state model of DFIM in dq frame.