Sensorless Disturbance Rejection Control Strategy for PMSM Based on SOGI-LTDFO

In order to address the problems of DC offset, harmonic filtering, low load torque capacity, and susceptibility to external disturbances in sensorless control of permanent magnet synchronous motors (PMSMs), this paper proposes a control strategy founded on a second-order generalized integrator load-torque disturbance flux observer (SOGI-LTDFO). The proposed method integrates an enhanced second-order generalized integrator flux observer (SOGIFO-X) with a load-torque disturbance observer (LTDO). The LTDO extracts torque information from the basic wave filtered by the SOGIFO-X and feeds it into the quadrature-axis input signal, improving the filtering performance, load-carrying capability, and disturbance rejection of the flux observer.