Sensorless Control of PMSM Drives Using Reduced Order Quasi Resonant-Based ESO and Newton–Raphson Method-Based PLL

This article proposes a novel sensorless control strategy for permanent magnet synchronous motor drives using reduced order quasi resonant-based extended state observer (ROQR-ESO) and Newton–Raphson method-based phase-locked loop (NRM-PLL). Due to the low-pass filtering characteristics, the conventional linear extended state observer (LESO) is not adequately able to track the fast-varying back electromotive forces (BEMFs). On this basis, the ROQR-ESO, which plants a ROQR controller into the internal model of conventional LESO, is presented to obtain BEMFs without phase lag. Moreover, the NRM-PLL, regarded as an improved finite position set-PLL, is proposed. After the rotor position is divided into four parts by utilizing a position quartering method, the extremely accurate rotor position can be obtained only by three iterations. In this method, no parameters need to be adjusted and great dynamic response can be achieved. The capacity of the proposed scheme is verified on a 750 W permanent magnet synchronous motor drive platform.