Abstract:

The performance of the traditional sliding mode observer (SMO) depends on the accurate mathematical model of the motor; consequently the deviation values of stator resistance and inductance generated during operation impact the observation. The effects of their deviation values on the observed result are analyzed. Then, Lyapunov stability theory is employed to design a novel adaptive SMO by which the observation of linear back-electromotive force of a brushless direct current motor (BLDCM) is achieved and the online identification of the stator resistance and inductance is implemented simultaneously. Simulation and experiment results demonstrate that the proposed strategy can be used to mitigate the impact of parameter error on the observer performance to some extent and estimate the stator resistance and inductance.

Key words: electrical engineering, brushless direct current motor, back-electromotive force observation, sliding mode observer, parameter identification, Lyapunov stability theory