Research Of Pitch-control System For Wind Turbine Based On Fractional Calculus

Recently One research is focus on the fractional calculus theory. Based on the fractional calculus theory, this paper works on control strategy of pitch-control hydraulic system for wind turbine,simulates with the Simulink tool of Matlab software and analyzes the control effects of pitch-control hydraulic system that each control strategy towards wind turbine. Some concrete contents are as follows:In the first instance, this paper studies the modeling of pitch-control system for wind turbine ,simply introduces the working principle of wind turbine as well as the theory basis of pitch-control system and how to apply automatic control theory of current fractional calculus to the control in wind turbine.In the next place, the article describes the fractional calculus theory which studies the time domain performances and the frequency domain performances ,judges methods of stability,robust and dynamic characteristics of control system for the controller on the theory basis of the fractional calculus and its control strategy .Meanwhile, we put how to find out the optimal value of both characteristics as our targets to adjust the parameters of the controller.For the second time,this paper uses the fractional-order control strategy based on Particle Swarm Optimization(PSO) and applies fractional control unit to pitch-control for wind turbin.In addition,we design the fractional controller based on Particle Swarm Optimization with the help of MATLAB/Simulink software designing controller and pitch-control system for wind turbin.The simulation results show that under the working of fractional controller, the pitch-control system for wind turbine has a good stability, good robust and dynamic performances. According to concepts and definitions of Particle Swarm Optimization,we compile programs with the combination with control theory and realize the algorithm of Particle Swarm Optimization using the powerful calculation of Matlab. The PSO optimization algorithm was introduced to obtain the minimal disturbance attenuation level and parameters of optimal controller which tabilized the closedloop system asymptotically.In conclusion, Simulation results show that the designed controller has good robust. The stability of the pitch-control hydraulic system for wind turbine shows obvious improvement after using the fractional control strategy, furthermore, the control system has a better dynamic characteristics.