Speed sensorless vector control of induction motor based on full-order flux observer

This paper presents a DSP-based speed sensorless field oriented vector control system for induction motor. A full-order adaptive observer with stator current and rotor flux as its state variables is used here to estimate the rotor speed. Moreover, the stator resistance is also identified to update the stator resistance value used in the observer so that the rotor speed can be estimated accurately at low speeds. By using the proposed full-order flux observer, the drive system can operate well in a wide range of speed. The validity of the proposed method is confirmed by numerical simulations. Then a prototype is setup and experiments based on a DSP TMS320F2812 prove the excellent performances of the presented control algorithm.