The Research Of Rotate Speed Control Of Wind Turbine Blade Based On Friction

Wind power is a kind of clean renewable energy. It can ease the environmental pollution and promote economic development. So it is very important to develop wind power. Wind turbine is a mechanical appliance which to use wind power. With the capacity of wind turbines increasing, how to improve unit efficiency of wind power technology becoming an important part of the wind power generator technology. The main three methods to control wind turbine are:pitch control system, fixed pitch stall control and variable speed control. Where the speed mode control of variable-speed constant-frequency wind energy generation system with double fed induction generator can achieve maximum wind energy tracking under the control of variable speed control, which has become a new focus in the field of wind power technology. Variable speed constant frequency technology is a high-speed operation of the current program.The blade of wind turbine is the only unit that can capture wind energy. It transforms the wind power into mechanical energy by the running of blade of wind turbine. The capturing power is determined by wind power source、wind energy performance coefficient of the wind turbine and the responding ability of impact wind of wind energy conversion system. The running of wind turbine can divide into four groups, which include potential promoter region, maximal wind energy conversion, rated power controlling and brake region. The paper introduces the interrelated knowledge of wind power generator, analyzes the present situation of wind energy utilization, and the speed control and the aerodynamics. At the same time, the paper analyzes the aerodynamic theory. According to the principles of how wind turbine to capture the maximum power, determined the variable speed constant frequency wind power operational phase and the mode, and then we made three types of speed control program. We designed the control device of rotating speed control of wind turbine. Through wind tunnel experiment, we got the correlated data. In this experiment, we use three type springs, different wind velocity and different eccentricity of blade.From analyzing the experiment data, we got the conclusion:the rotating angle is proportional with the wind speed; the bigger eccentricity, the bigger rotating angle in the same wind velocity; and the bigger spring constant, the smaller rotating angle in the same wind velocity. The experimental results and conclusion have certain reference value for designing and rotating speed control of wind turbine blade.