PMSM Disturbance Resistant Adaptive Fast Super-Twisting Algorithm Speed Control Method

To realize advanced velocity regulation for permanent magnet synchronous motors (PMSM) in servo control and enhance the capability to resist disturbances of load and inertia, a disturbance-resistant adaptive fast super-twisting algorithm (FSTA) speed control method is proposed. To address the challenge of of chattering caused by the conventional exponential reaching law in sliding mode control (SMC), a FSTA reaching law is proposed. Introducing an integral sliding surface simultaneously to avoid the requirement of PMSM acceleration in the control input, decreasing the static error of the system. Furthermore, replacing the sign function sgn(s) in the FSTA reaching law with the continuous function sigmoid(s) to further enhance the system’s responsiveness and stability in varying conditions. To address the issue of system instability caused by inertia and load variations, an extended sliding mode observer (ESMO) and model reference adaptive system (MRAS) method are for the purpose of achieving real-time observation of load torque and rotational inertia, respectively. The observed torque values and identified inertia values are then updated in the FSTA control, enabling adaptive FSTA speed control. The outcomes of the experiment show that, compared to the traditional adaptive SMC and STA speed control method, the proposed adaptive FSTA control method in this paper exhibits superior dynamic performance and stronger disturbance rejection capability against load and inertia.