A sliding-mode observer design for the unknown disturbance estimation of a PMSM

This paper proposes a sliding mode observer (SMO) for a permanent-magnet synchronous motor (PMSM). The unknown disturbance of a PMSM can be identified based on the measurable current and the position, then the estimation is used to enhance the robustness of the speed control dynamics. For ease of implementation in real application, such as DSP and FPGA, etc, the proposed observer is properly designed to avoid complex mathematical operators. The validity of the proposed sliding mode observer has been demonstrated with the simulation results.