Adaptive torque-ripple minimization in switched reluctance motors

This paper addresses torque-ripple reduction in current-fed switched reluctance motors (SRMs). Ripple-free torque production in SRMs requires an accurate model that is often too complex for practical implementation. The algorithm proposed here combines the use of a simplified model with adaptation. Explicitly, it includes dynamic estimation of low harmonics of the combined unknown load torque and the ripple in the produced torque (due to model simplification), and adds appropriate terms to the commanded current to cancel these harmonics. Several simulations are presented first, suggesting that our method is effective for constant-speed reference commands, even when a very simple model is used in control design. Experimental results are included next to demonstrate that the algorithm performs well in reducing the torque ripple. Finally, limitations of the adaptive algorithm are explored and quantified.