Adaptive speed identification for vector control of induction motors without rotational transducers

A model-reference adaptive system (MRAS) for the estimation of induction motor speed from measured terminal voltages and currents is described. The estimated speed is used as feedback in a vector control system, thus achieving moderate bandwidth speed control without the use of shaft-mounted transducers. This technique is less complex and more stable than previous MRAS tacholess drives. It was implemented on a 30 hp laboratory drive, verifying its effectiveness.<
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