A Novel Nonsingular Terminal Sliding Mode Observer-Based Sensorless Control for Electrical Drive System

To improve the sensorless control performance of electrical drive systems, a nonsingular terminal sliding mode observer (NTSMO) and adaptive are proposed to solve chattering phase delay problems. Firstly, by defining new surface, based on fast reaching law is designed estimate back electromotive force (EMF). The enhances robustness system eliminates singularity attenuates chattering. Next, obtain accurate back-EMF signal, an instead traditional low-pass filter out harmonics. can avoid problem further signal observation accuracy. Then, rotor position speed information accurately tracked. method applied permanent magnet synchronous motor (PMSM), effectiveness feasibility demonstrated experiment.