Modified Discrete-Time Super-Twisting Control of PMSM Speed Regulation System: Theory and Experimentation

The article puts forward a modified discrete-time super-twisting (DTST) control strategy for the speed regulation system of permanent magnet synchronous motor (PMSM) to strengthen the control efficacy and resilience to disturbances in its digital execution. As opposed to the conventional DTST algorithm, the most discernible attribute for the developed scheme is to displace the discontinuous term in the conventional DTST by dint of a nonsmooth term in consequence of the constraint of the sampling frequency practically speaking. With consideration for this substitution, a flexibly tunable fractional power parameter is introduced to increase the control precision while mitigating the oscillations. The Lyapunov-based theoretical analysis is offered to rigorously validate the convergence for the correspondingly whole system. Eventually, in comparison with two existing control schemes, the effectiveness and superiority of the presented method are experimentally supported in real time through using a 1.5 kW PMSM hardware platform.