Weld Strength Analysis And Structure Optimization Of Large Wind Turbine Tower

The large-scale wind turbine tower, as the important part of wind turbine-generator system, the fatigue property of its welded part affects the safety and reliability of wind turbine directly. For this purpose, the 2.0MW wind turbine tower was chosen as the research object, the ultimate strength and fatigue life of welded part of tower was analyzed.For the tower’s longitudinal weld which was produced, because the tower adopt steel plate to roll and weld, based on 18800-4 calculation method of section stress, using engineering algorithm and fatigue simulation software in combination, according to the requirement of GL2010 specification, the ultimate strength and fatigue property of the longitudinal weld was analyzed, a effective approach to analyze the static strength and fatigue strength of the longitudinal weld joint of tower structure was provided.For the T-fillet weld of tower door, based on establishment of finite element model of tower door, according to the requirement of GL2010 specification, using finite element method and fatigue simulation software in combination, the ultimate strength and fatigue property of T-fillet weld of tower door was analyzed, obtained the most dangerous position that was the weld toe of inner wall of tower door, and checked the fatigue of tower door whether met the requirement of 20 years, a effective approach to analyze the static strength and fatigue strength of the T-fillet weld joint of tower door was provided.Based on the analysis of fatigue property of tower door, the maximum accumulated damage of weld joint of tower door was optimized by altering thickness of tower wall, width of door frame, length of door frame, the optimized tower door’s fatigue strength met the requirement of GL2010 specification.Different analysis method was proposed for different weld part of tower, which could calculate the static strength and fatigue strength of weld joint, and the feasibility and effectiveness of the proposed approach were verified by a practical example, which provided theoretical significance and engineering practical value to the design and analyze of the structure of wind turbine tower.