Optimization-based Gain Tuning Method of Sliding-mode-based Flux Linkage Observer for PMSM with Wide Operating Range

The second-order sliding mode observers (SOSMOs) have proved to provide good robustness against parameter variation while maintaining a good dynamic response. This paper presents an efficient gain-tuning method for stator flux linkage SOSMOs in permanent magnet synchronous machines (PMSMs). The tuning of SOSMO gains is essential to achieve the adequate performance of the observer. However, this is challenging under varied operating conditions. To alleviate this issue, the proposed method involves two steps. Firstly, a set of optimal gains is obtained by optimizations at each operating point. Secondly, based on the optimized gains, lookup tables are created in order to adapt to the operating condition variation. A simulation study is conducted to demonstrate the effectiveness of the proposed tuning method.