PUBLICATIONS

This paper presents an adaptive speed tracking control scheme for an uncertain surface-mounted permanent magnet synchronous

motor (SPMSM) without any knowledge of the SPMSM parameters and the singularity problem; further, even the upper and lower

bounds of the parameters are not necessary. The contribution of this study is twofold. The first one is to introduce a coordinate

transformation so that the resulting controller does not suffer from a singularity problem caused by the denominator including the

parameter estimates. Besides, although the number of the unknown parameters is increased by two times, the number of estimators

is the same as the previous result. The second one is to prove that the slightly modified parameter adaptation law contributes in

enhancing the closed-loop robustness against the disturbance caused by the time-varying component of the load torque. The

effectiveness of the closed-loop performance is shown by performing the experiment using the 3-kW SPMSM without any SPMSM

parameter knowledge.