Research On The Hydraulic Mechanical Control System Of Wind Turbine

Nowadays, energy and environment is an urgent problem to solve for the survival and development of human beings. Conventional energy sources are coal, oil and natural gas, which not only have limited resources, but also cause serious air pollution. Therefore, the development and utilization of renewable resources, especially the development and utilization of wind energy, has been highly valued by countries around the world. China’s wind power installed capacity and wind power equipment manufacturing scale are all among the best in the world, but in terms of the technical level of wind power generation, no matter is in the wind power equipment manufacturing or in wind farm connected to power system operation, our country still has a big gap from the world advanced level. Although we have learned from the foreign advanced technology, we are still in the stage of digestion, understanding and absorption. In general, the research on the constant speed control system of the wind power generation hydraulic machinery has just started in China.Compared with the traditional variable speed constant frequency wind turbine, the hydraulic variable speed wind turbine by mechanical speed and not variable frequency device can ensure the synchronous generator power frequency constant, so as to improve the wind turbine reliability, reduce the cost of power generation, the weight of the wind turbine, decreases the size of the cabin, convenient installation. At the same time, the hydraulic transmission is applied to the field of wind power, to broaden the application scope, to promote the development of the hydraulic transmission hydraulic transmission is very important.The main research contents of this paper:(1)The mathematical model of the adjustable hydraulic torque converter is established based on the principle of curved surface fitting. The influence of order and weight function on fitting precision is studied, and the conclusion is drawn that the higher the order is, the higher the fitting precision is, and the fitting accuracy can be improved by adjusting the size of the weight function.(2)Establish a static mathematical model of the wind power transmission system, the static mathematical model of the wind power transmission system is the basis of the design and analysis of the hydraulic mechanical control system of wind power generation. The mathematical models of wind turbine, gear b ox, synchronous generator and guide vane control mechanism are established respectively. Wind power generation system use hydraulic servo position control system to regulate the guide vane opening. Use the model library of AMESim software to build the model of the valve controlled hydraulic cylinder system. Set the parameters reasonably and obtain the ideal response curve.(3) Establish the dynamic mathematical model of wind power generation system, then build a dynamic simulation model of transmission system in the platform of MATLAB/Simulink. According to the characteristics and requirements of wind turbine, design the corresponding control system. The hydraulic speed wind turbine drive system is simulated using MATLAB/Simulink and AMESim software. Under different wind speed, the designed controller can quickly response to the changes of wind speed. At the same time, adjusting guide vane opening makes the wind wheel track the optimal wind energy utilization coefficient, ensures the speed of synchronous generator keep synchronous speed and limit the power within the range of maximum power.