An improved flux observer based on PLL frequency estimator for sensorless vector control of induction motors.

Mihai Comanescu Longya Xu An improved flux observer based on PLL frequency estimator for sensorless vector control of induction motors. 50-56 2006 53 IEEE Trans. Ind. Electron. 1 https://doi.org/10.1109/TIE.2005.862317 db/journals/tie/tie53.html#ComanescuX06