A simple rotor current observer with an arbitrary rate of convergence for the brushless doubly-fed (induction) machine (BDFM)

The BDFM shows economic promise as a variable speed drive or generator. One practical obstacle to commercial exploitation is the presence of operating speeds at which BDFM synchronous action cannot be maintained under open loop conditions. The authors proposed a control strategy using feedback linearization, requiring full state feedback. We present a simple rotor current observer with an arbitrary rate of convergence. Simulation results are given to validate the performance.