Back EMF Estimation-Based Sensorless Control of PMSM: Robustness with Respect to Measurement Errors and Inverter Irregularities

In this paper, the influence of measurement errors and inverter irregularities on the performance of sensorless control is studied. The control algorithm is based on the back-electromotive-force estimation whose robustness with respect to the machine parameter uncertainties has been already studied by supposing that the current measurements and the power stage are ideal. Here, these hypotheses are removed and it is shown, analytically and experimentally, that the control performances at low speeds are highly affected by the imperfection of the electronic components. Finally, the interest of online stator resistance estimation improving the sensorless control performances in spite of the above disturbances is presented.