Adaptive Sliding Mode Observer for Back-EMF in Direct Torque control of Brushless DC Motor

摘要

The key issue of feedback torque calculation in BLDCM-DTC system is how to get the accurate estimation of back-emf. The influences form the deviation of resistance and inductance on traditional back-emf sliding mode observer (SMO) and relevant torque observation results are analyzed. To advance the accuracy of the torque estimation, an adaptive sliding mode observer is designed to estimate the back-emf of the BLDCM and then get torque estimation from the back-emf estimation. The proposed sliding mode observer can also implement the online identification of the stator resistance and inductance simultaneously. Simulation results demonstrate the proposed method is valid and effective.