Novel motion sensorless control of single phase brushless D.C. PM motor drive, with experiments

A motion sensorless control for single phase permanent magnet brushless d.c. (PM-BLDC) motor drives, based on flux integration and prior knowledge of the PM flux/position characteristic is proposed here and an adequate correction algorithm is adopted, in order to increase the robustness to noise and to reduce the sensitivity to accuracy of flux linkage estimation. An I-f strategy is used for starting, by prescribing a ramped reference frequency and a constant current, and then the seamless transition to close loop sensorless control takes place. The proposed control system is detailed and validated by simulation and experimental results.