Design method of adaptive full order observer with or without estimated flux error in speed estimation algorithm

The performance of adaptive full order observer for sensorless induction motor drives can be improved further though it has been researched for many years. In this paper, two different design methods for improving the speed estimation stability and robustness are proposed: 1) In classical speed estimation algorithm used in adaptive full order observer, the estimated rotorflux error is neglected. A robust design method of feedback gains with classical speed estimation algorithm is proposed. Compared with existed three main design methods of feedback gains, the stability of speed estimation and estimated speed error are improved. 2) A robust speed estimation algorithm with estimated rotor flux error and the corresponding feedback gains are proposed in this paper. Through Lyapunov's theorem, the stability of proposed speed estimation algorithm is proved. The stability of flux estimation and estimated speed error can be improved much more. Finally, the feasibility of two proposed methods is verified by experiments.