Modeling The Differential Gear Box Enbeded In A New Type Of Wind Turbine And Its DLL Development Under Bladed

With the global climate warming and energy crisis, countries all around the world are taking great effort in the development and utilization of wind power. The capacity of generator sets with wind turbine is gradually growing in electricity grid. At the same time the requirements for parallel operation of wind turbines would be increasingly strict that includes the riding-through ability with low voltage, the distortion of voltage waveform and the support capability of generating sets of wattless power. However, the double-feedback models, the leading ones in the market so far, are not competent well to cope with the requirements above. Besides, another leading category of turbine models of direct-drive with permanent magnetism only have limited prospects due to the excessive costs both in production and maintenance.With the basis of incorporation of the advantages of the current leading turbine models and the comprehensive consideration of the grid necessity, this project proposed a new type of wind turbine with variable speed and constant frequency based on a gear box with variable gear ratio which provided the advantages of friendly property to electricity grid, working with low-power frequency converter and strong low-voltage riding-through ability. And the project team carried out study around the turbine structure and the designing and simulation of the control system. The biggest difference between the new wind turbine and the ordinary type was the addition of the differential variable-ratio gear box which was just the keypoint this thesis focused on.The main contributions of the work are fourfold. First, analysis and comparison on the new wind turbine model and the control methods was provided. Secondly, meticulous exploration and explanation for the dynamic link library (DLL) interface of Bladed external gear box were carried out. Such effort has not been made in the wind turbine research area before. Then, the arithmetic model according to the relationship of different transmission components of the gear box was built with its simulation. The focus was on GH Bladed commercial wind turbine simulation software. Finally, this thesis briefly described the turbine simulation platform which was preliminarily built in accordance with the estimation of output axis torque of the gear box and laid the conditions for follow-up analysis of the load calculation...