The Research On Independent Pitch Control Strategy Of Wind Turbine

Wind power plays an important role in the development of renewable energy due to its characteristics of green,clean,and high development and utilization.With the increasing use of large wind turbines,problems with wind turbines in terms of starting,braking performance and output power stability have also emerged.The pitch system with traditional PID parameters is not ideal for large wind turbines.Independent pitch technology is a variable pitch control system based on unified pitch technology.By individually adjusting the pitch angle of each blade according to the realtime wind condition feedback,the uneven load generated by the wind shearing effect,the tower shadow effect and the turbulence effect can be better reduced,and the power output is stabilized.Improve the output performance of the unit and increase the service life of the unit and various components.In the design process of this paper,the basic theory of the fan,the power control model,the improvement based on the standard particle swarm optimization algorithm and the PID controller of the pitch system are deeply analyzed and discussed.The main work includes the following aspects:(1)Explain the background and significance of the topic,and introduce the prospects and development trends of wind power generation,the development of wind power technology worldwide,and the research of pitch technology.Some problems in the current research on independent pitch technology are proposed.(2)The aerodynamic principle and the principle of leaf momentum are introduced.Based on these principles,the characteristic parameters and vibration analysis of wind turbines are described,and the theory of pitch control of wind turbines is introduced.The principle of independent pitch and collective pitch control of wind turbines is analyzed,and the advantages of independent pitch control systems are proved.A joint pitch control system is also introduced.(3)The main components of the wind turbine power control are introduced,including: generator model,gearbox model and inverter model.The model of 5MW wind turbine was built in Matlab/Simulink,and the traditional PID control method was used to simulate the independent pitch control system of the unit.The control effect of the traditional PID controller under large wind speed and fluctuation was obtained.Not an ideal conclusion.(4)The basic theory of particle swarm optimization algorithm is introduced,including the original particle swarm optimization algorithm and the improved standard particle swarm optimization algorithm.In order to enhance the local and global search ability of the algorithm,an improved algorithm based on standard particle swarm optimization algorithm is proposed.The principle of the PID controller is elaborated,and the improved particle swarm algorithm is combined with the PID controller.The simulation of 5MW wind turbine independent pitch control system based on improved particle swarm optimization PID parameters was carried out,and the independent pitch system using traditional PID controller was compared in terms of unit speed,power and load,which proved the former.The superiority and feasibility.(5)Finally,the design and analysis of this design are summarized,and the shortcomings in the design process and the prospects for future work are put forward.