Globally convergent nonlinear observer for the sensorless control of surface-mount Permanent Magnet Synchronous machines

For a surface-mount Permanent Magnet Synchronous Motor (SM-PMSM) with currents and voltages as only measurements, we propose an observer estimating the rotor electrical phase. It comes from an appropriate choice of coordinates and exploits convexity. We prove its global convergence under the only assumption that the rotor does not stop. Experimental results assess the validity of the proposed observer.