BLDCM speed observer based on scale-corrected minimal skew simplex sampling UKF

In this paper, a scale-corrected minimal skew simplex sampling UKF algorithm for BLDCM sensorless control has been studied to cancel the position sensor by use of a systematical, analytical approach. Compared with general UKF, to reduce amount of computation and increase the estimation precision, the sampling method with the least Sigma points called minimal skew simplex sampling is adopted. Moreover, the scale-corrected strategy is introduced into the minimal skew simplex sampling UKF to overcome the nonlocal effects. On the other hand, for more easily calculating the value of back-EMF, the shape function of counter electromotive force is approximated by a series of sine and cosine functions based on the law of Fourier series. Finally, the effectiveness of proposed sensorless technique is verified through simulation in MATLAB/Simulink, which is validated by complete simulation results on BLDCM.