Single sensor three-phase permanent magnet synchronous motor drive based on Luenberger style-observers

This paper presents a technique to estimate phase currents and rotor position in a vector-controlled PMSM drive using only dc-link current measurement. Three cascaded Luenberger style observers were used to perform this task. The first one estimates phase currents and motor back emf while the other two observers estimate the rotor position and velocity. The estimated signals were compared to the actual ones and their effects on the drive performance were reported.