Modeling And Intelligent Control Technology Research On Variable-speed Variable-pitch Wind Power System

Nowadays, the consumption of energy resources is growing and environment pollution isseriously, so people pay more attention to the development of new energy. As a renewable and greenenergy, wind power is taken seriously by the world and become focus of the research among scholars.Variable-pitch power control is one of the most important technologies on large scale wind turbine. Inthis thesis, base on variable-speed variable-pitch wind turbine, studied system controller design andsimulation, classical control method and intelligent controller design, then analysed the traditionalbinary switch logic and designed intelligent switching algorithm.Firstly, according to aerodynamics knowledge, established subsystem models of variable-speedvariable-pitch wind turbine and wind speed model, then verified validity and rationality of the model;According to the control requirements of the wind generator, in the case of below the rated windspeed, control generator torque so that tracking the best power curve, in case of above the rated windspeed, control pitch angle to restrict the transformation of the wind power, cooperate generator torquecontrol to make the output stable nearby rated power, then respectively design PID controller of thetwo stage, and verify two kinds of state under PID control through simulation.Secondly, Aiming at strong nonlinear characteristics on wind turbine, the performance of thetraditional PID control is not very ideal, so intelligent robust control technique is applied tovariable-speed and variable-pitch control of wind turbine in order to obtain more stable performance,then made comparative study with classic PID control and verified exactness and effectivenessthrough simulation platform.Thirdly, due to randomness of wind disturbance, the modal transformation and smoothlytransition between the two stage controller that even affect power quality and fatigue load of windturbine is especially important, so as the emphasis of optimized design, the transition mode is aimingat the good performance of the two stage controller, and ensuring the smooth transition of frequentswitching.Finally, combined with the switching algorithm and variable-pitch controller, this paper verifiedthe performance of the wind turbine generator through a system integrated design and simulation.Then designed a fuzzy-PI dual mode switch controller for variable-pitch, the simulation analysisresult showed the effectiveness and rationality of the control system design.