Speed Tracking Switching Optimal Control Of Doubly Fed Wind Power Generator

The rapid growing construction of wind power plants around the world, researchersincreasingly focus on VSCF doubly fed wind power generation technology,because ofits high efficiency and good economy.So only double fed wind turbine is effectivelycontrolled well in VSCF wind power generation system, it can be of tracking capabilitywith high efficiency and precision and achieve maximum wind power tracking.The maincontents of this dissertation are that the switch control is applied to the double fedinduction generator(DFIG) control system combined with optimal control. Firstly, forthe double fed induction generators have the characteristics of more coupling andnonlinear.etc, a fifth.order nonlinear model be established in the based stator fluxoriented synchronous rotating coordinate system, which is closer to the actual objectand presents more good dynamic performance.Since this model is a fifth.order nonlinearmodel and the use of nonlinear control methods to solve it are complex, linearizing thenonlinear system around an operating point is presented so that.matural linear controlmethods can be used.Secondly, since the switching control nature of solving the problemof complex system, in recent years, its theory study is widely popular and onging maturein the world,along with begining to be applied to all areas of practice.so a generatorspeed tracking switching optimal controller is designed based on the combination ofswitch control and optimal control by the corresponding system parameters of doublefed motor at different operating points. when the generator is running at the time of thework state,then the appropriate controller is switched to it. The ideal of the control is bycontrolling the voltage of the generator rotor side to adjust the angular velocity of thegenerator to track the optimal angular velocity.thus,the dynamic performance of thesystem is improved.Then,A11kW wind generator is considered to illustrate the goodperformances brought by the proposed approach by presenting and discussing thesimulation results,and so the proposed switching system can meet the need of actualproject well.Finally,the full dissertation is summarized.