Active-Flux-Based Super-Twisting Sliding Mode Observer for Sensorless Vector Control of Synchronous Reluctance Motor Drives

This paper proposes an active-flux-based rotor position and speed estimation scheme for sensorless-vector-controlled synchronous reluctance motor (SynRM) drives, which is comprised of two main parts: 1) a super-twisting sliding mode observer (ST-SMO) for estimating the derivatives of active flux components; and 2) a rotor position and speed estimator based on the phase-locked loop (PLL). The ST-SMO is designed based on the active flux model of the SynRM in the stator reference frame. The estimated active flux components, which are obtained based on the ST-SMO and the integrator, are received as inputs of the PLL, and the estimated rotor position and speed are provided as outputs of the PLL. The feasibility and effectiveness of the proposed estimation scheme have been verified by the simulation results.