Regenerating-Mode Stabilization of the “Statically Compensated Voltage Model”

Reversal of rotation under load of sensorless induction motor drives is very challenging, as there is often an unstable region in the low-speed regenerating mode. In this paper, a variant of the classical "voltage model", i.e. the "statically compensated voltage model", is modified for stable regenerating-mode operation with accurate model motor parameters. The mechanisms behind two low-speed instability phenomena are thereafter explored, and methods for avoiding instability with inaccurate model parameters are developed. Experimental results verify the theory and show adequate performance