Gain-Scheduled H-infinity Control for WECS via LMI Techniques and Parametrically Dependent Feedback Part I: Model Development Fundamentals

Simulation has become the most important technique used today for evaluation of engineering solutions, and modeling plays a crucial part in the design of intelligent control paradigms for complex dynamic structures. For the analysis of a megawatt-class wind-energy conversion system (WECS), this research adopts the H-infinity control theory in designing an advanced control paradigm that accomplishes the dual purpose of energy capture optimization, as well as power train cyclic load alleviation by mitigating against wind-speed fluctuations. This work is presented in two parts: The first details the modeling of the subsystems of WECS and introduces the multiobjective H-infinity control concept, and the second deals with the implementation of the control paradigm. Presented herein is a modeling approach of individual subsystems as a basis for devising the unified control strategy for a 2-MW grid-connected pitch-regulated variable-speed WECS that incorporates a doubly fed induction generator. The credibility of the archetype, to establish the argument that the models produce sound insights and comparable results to data from the real system, is ascertained via validation.