document: Active pitch control in larger scale fixed speed horizontal axis wind turbine systems . I. linear controller design This paper reviews and addresses the principles of linear controller design of the fixed speed wind turbine system in above rated wind speed , using pitch angle control of the blades and applying modern control theory . First , the nonlinear equations of the system are built in under some reasonable suppositions . Then , the nonlinear equations are linearised at set operating point and digital simulation results are shown in this paper . Finally , a linear quadratic optimal feedback controller is designed and the dynamics of the closed circle system are simulated with digital calculation . The advantages and disadvantages of the assumptions and design method are also discussed . Because of the inherent characteristics of the linear system control theory , the performance of the linear controller is not sufficient for operating wind turbines , as is discussed
doc_bio_tags: B I I O O O O O B I I I I O O B I I O O O O O O O O B I I O O B I I I I O O O O O O O B I I O O O O O O B I O O O O B I O O O O O O O O O O O O O O B I O O O O O O O B I O O O O O O O O O O B I I I I O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O
extractive_keyphrases: fixed speed wind turbine system pitch angle control control theory nonlinear equations digital simulation linear quadratic optimal feedback controller closed circle system wind turbines horizontal axis wind turbine systems active pitch control linear controller design
abstractive_keyphrases: linear system control theory aerodynamics drive train dynamics