Terminal voltage control of variable speed induction generator driven by a wind turbine supplying a DC load

This paper presents a new method for the voltage build-up process of an isolated-loaded induction generator (IG) driven by a wind turbine including the variation in the value of magnetizing inductance. The machine delivers an active power to the load via a converter connected to a single capacitor on the dc side. So, during the voltage build-up process, the necessary stator currents references to be injected by the converter can be calculated from the desired active power to be sent to the load which is determined by the dc-bus voltage regulation the reactive power required for the machine magnetization and finally from the three instantaneous voltages induced. Since the converter/capacitor model is nonlinear, a fast and simple control strategy based on the input-output feedback linearization technique is applied to ensure the dc-bus voltage regulation. The computer simulations are provided to verify the validity of the proposed control algorithm.