Full State Observer with Finite Time Convergence for Permanent Magnets Synchronous Motors

In this paper, we address the problem of observer design for permanent magnet synchronous motors (PMSM). The only measured signals are stator current and control voltage, and all parameters of the PMSM model except flux from permanent magnets are known. The load torque is unknown and assumed to be constant or slowly time-varying. The approach is based on a new way of applying the Dynamic Regressor Extension and Mixing method (DREM) to regression models with non-stationary parameters, which is recently proposed and called DREM-based adaptive observer (DREMBAO). In this work, we extend the previous result and design a full state observer with finite-time convergence. On the first step, the flux and position observer is constructed. On the second step with these estimates, the rotor speed and load torque are reconstructed.