电瓷避雷器Issue(1)：1-9,9.DOI:10.16188/j.isa.1003-8337.2025.01.001
风机叶片-轮毂连接引下线及其接线端子雷击电磁热-力特性分析及结构改进
Analysis of Electromagnetic-Thermal-Mechanical Characteristics and Structure Improvement of Fan-Blade Hub Connecting Downlead and Its Terminals Under Lightning Strike
摘要
Abstract
Lightning accidents often lead to the burning of wind turbine communication components and automatic control,generator breakdown,electrical equipment damage,etc.Multi-physics field research is carried out for the engineering fault phenomenon of frequent sparking and terminal falling off on the blade-hub connection downlead during the transient process of lightning grounding in wind turbines:the lightning current is decomposed into independent impact analysis considering skin effect at each frequen-cy,Then,according to the calculated current density distribution of the downlead at different frequencies at each time,the electromagnetic heat mathematical model of the downlead is constructed;Calculate and analyze the influence of the axial electromagnetic force direction of the horizontal section and the vertical section of the downlead against the bending section;The terminal contact force model is established by combining the three important parameters of contact resistance,temperature and preload to explain the terminal shedding phenomenon of the connection channel.Finally,the design defects of the connection link are summarized through 7 conducted current tests.In view of the lack of thermal and dynamic stabil-ity of the connecting channel,the temperature rise model of multi-core stranded wire based on Tourkha-ni formula and the influence of different bolt fastening and lapping forms and different preload on the dy-namic stability of the terminal are verified by finite element software.The results show that selecting the 7-core stranded wire with a pitch ratio of 60 can reduce the temperature rise and fall to 27.4%of the o-riginal value,and the contact force of M16 bolts with a pretension of 230 N·m single-hole lap joint can be reduced to 8.4%of the original value,and the bending section of the down lead needs to be fixed with a T-shaped bracket.关键词
叶片-轮毂连接引下线/多物理场/电磁热/轴向电磁力/热、动稳定Key words
blade hub connection downlead/multiple physical fields/electromagnetic heat/axial electro-magnetic force/thermal and dynamic stability引用本文复制引用
黄煜涛,夏能弘,阮庆洲..风机叶片-轮毂连接引下线及其接线端子雷击电磁热-力特性分析及结构改进[J].电瓷避雷器,2025,(1):1-9,9.基金项目
国家自然科学基金青年项目(编号:51607110).Project supported by Youth Project Supported by National Natural Science Foundation of China(No.51607110). （编号:51607110）
