Nonlinear integral sliding mode control of SPMSMs using a dual-layer adaptive super-twisting algorithm

Surface-mounted permanent magnet synchronous motors (SPMSMs) require advanced speed regulation strategies due to their nonlinear dynamics and sensitivity to disturbances. Conventional integral sliding mode control (ISMC), when applied to these drives, faces critical drawbacks such as saturation effects caused by large initial speed errors and adaptive gain overestimation in super-twisting algorithms. To address these challenges, this paper proposes a nonlinear integral sliding mode control scheme enhanced with a dual-layer adaptive super-twisting algorithm (NISMC-DASTA). A novel integral sliding surface with a dynamic anti-saturation gain mechanism is introduced to accelerate error convergence, enhance disturbance rejection, and mitigate integrator windup. Additionally, a dual-layer adaptive mechanism is embedded within the super-twisting controller to adjust its gains dynamically. This two-tier adaptation not only suppresses chattering but also alleviates the trade-off between rapid convergence and excessive gain amplification commonly observed in single-layer adaptive STA approaches. Extensive simulations and experimental results on a practical SPMSM drive platform validate the superior performance and robustness of the proposed NISMC-DASTA method.