Abstract-In a permanent magnet (PM) brushless dc motor (BLDC), the performance of Hall effect sensors are not reliable in some applications. The back electromotive force (back-EMF) signal is used instead since the zero-crossing points of back-EMF can be used to provide the rotor position information. In this paper, a new back-EMF difference detection method based on disturbance observer is proposed. The proposed structure can detect the back-EMF as well as back-EMF difference signal. The zero-crossing points of the back-EMF difference can be used directly for commutation, requiring no phase shift. Simulation and experiment results are provided to show the feasibility of the proposed method.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.