State observers for variable-reluctance motors

A sequence of progressively more complex state observers, each driven by measurements of phase voltages and currents, is developed for variable-reluctance motors. For the simpler observers, the exponential stability of their error dynamics in a neighborhood of the origin is proved. For all observers, the results of numerical or physical experiments are provided to demonstrate the globally stable error dynamics. In several of the physical experiments, rotor position is estimated to better than one part in 50000 of a revolution.<
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