The Desig And Development On The Variable Pitch System Of2MW Wind Turbine Group

With the rapid development on industry of the countries around the world, oil, gas, coal and other natural energy sources are depleting day after day. New energy sources have become the field that people are concerned about very much. As a kind of new energy sources, wind power generation has a wide source, and it do not have pollution. In addition, wind power generation is around the clock. Megawatt wind turbine power generation becomes the mainstream on wind power industry due to its large mainstream. Aiming at variable pitch system of2MW wind turbine, this paper has completed the design and development independently.Firstly, this paper analyzes the composition and working principle of wind turbine. The whole main circuit on2MW doubly-fed wind turbine machine is designed using PCC AD software. The main circuit of variable pitch system is also designed after analzing the composition and function on each part of the variable pitch system. The main circuit system designed fit well with wind turbines to meet the requirements of various operating conditions.Secondly, the analysis on how the tip speed ratio, pitch angle and other parameters affect wind turbines on getting wind power. Depth study is made on how to improve the efficiency of wind turbines by controlling these parameters and how to run best in all kinds of operating conditions, on which the control strategy of pitch system is raised based on.Thirdly, being aimed at2MW wind turbine, mathematical model such as wind model, wind turbine model, and transmission model are established in this paper, also,2MW wind turbine pitch control system model is simulated by Matlab/Simulink software based on the mathematical models and variable pitch control strategy.Finally, the ultracapacitor is choosed as backup power replacing batteries in variable pitch system. Then choose the model parameters for ultracapacitor. Afterwards, the experiments on automatically back paddle and self-discharge of ultracapacitor module have been done.Through the study on variable pitch system of wind turbine, it can be concluded as follows:First, the simulation results of the variable pitch system show that the power of wind turbine can be controlled around the rated power by changing the pitch angle in the designed variable pitch system; Second, the ultracapacitor experiment shows that it is feasible for ultracapacitor to replace batteries as the backup power of variable pitch system. Moreover, the voltage is well balanced.