Sensorless PMSM Control Algorithm for Rim-Driven Thruster Based on Second-order Sliding Mode Observer

In order to solve the problem of poor speed and position observation performance of the Permanent Magnet Synchronous Motor (PMSM) of rim-driven thruster (RDT), a second-order sliding mode observer based on super-twisting algorithm (STA) is presented. The new algorithm to external interference of and effectively weakens the “chattering“ phenomenon. The new algorithm can effectively suppress the sliding mode chattering and retains the advantages of traditional sliding mode observer algorithm such as strong robustness and insensitivity. The simulation results show that the speed and position error and chattering of the proposed second-order sliding mode observer are reduced compared with traditional SMO.