Rotor design for sensorless position estimation in permanent-magnet machines

A high-frequency injection sensorless rotor position estimation algorithm is incorporated directly into the finite-element design process to realize a permanent-magnet (PM) machine that is suited to zero- and low-speed sensorless control. The machine design is tightly constrained by an existing stator assembly, only enabling the redesign of the replacement PM rotor, and by the requirement that the manufacture of the resulting machine must be simple while meeting aerospace standards. Experimental results confirm that the resulting machine matches the original performance specification and that it operates under position sensorless control.