Self-adjusting and fuzzy logic gain schedulers for vector control of wind driven doubly-fed induction generator

Wind is one of the most efficient renewable energy sources available. Wound-rotor induction generators, specifically the doubly-fed induction generator, have numerous advantages in wind power generation in comparison to other generators. Doubly-fed induction generators use a converter cascade between the slip-ring terminals and the utility grid to control the rotor power. A vector control scheme developed to control the rotor side voltage-source converter allows independent control of the generated active and reactive power, as well as the rotor speed in accordance with the maximum power point. This paper proposes two different schemes by which the vector controller can fine-tune its proportional and integral gains. The first scheme is a self-adjusting gain scheduler, which uses different characteristics such as linear, exponential, etc. to generate a variation in the proportional and the integral gains. The second scheme is a fuzzy logic gain scheduler. The paper analyses and compares the transient responses of the system employing the proposed schemes. © 2012 Taylor and Francis Group, LLC.