提出在风力机塔筒上加设碳纤维增强塑料(carbon fiber reinforced plastics,CFRP)拉索和相应的锚固体系形成CFRP锚索型风电结构。基于不随高度变化的台风功率谱和自回归(AR)法模拟并验证沿海某风电场的台风风场。建立风力机一拉索一基础有限元模型,进行模态分析和台风作用下的非线性动力时程分析。结果表明,锚索型风电结构的各阶自振频率较常规型风电结构有所增加,其中一、二阶频率增加约20%。其轮毂水平位移、塔筒底部等效应力、基础环等效应力和最不利单桩轴力均比常规型风电结构显著减小,拉索内力也留有足够的设计裕度。锚固体系估算成本仅占单体风力机建设成本的1.875%。
A new type of wind power structure with CFRP cables is proposed. CFRP cables are installed on the tower and fixed by a multiple CFRP tendons bond-type anchor system on the ground. Based on a power-spectrum-density (PSD) model of typhoon unchanged with altitude and the auto-regressive (AR) method, the typhoon wind field of a coastal wind farm is simulated and verified. A finite element model, including wind turbine, cables and pile foundation, is established. Modal analysis and nonlinear transient dynamic analysis are conducted not only on the conventional wind power structure but also on the presented one. Results showed that the natural frequencies of the presented structure are higher than the conventional structure. The primary and secondary frequencies increase about 20%. The horizontal displacement of the hub, the equivalent stress of the tower bottom and the anchor ring, and the axial force of the most unfavorable piles are reduced significantly in the presented structure. Moreover, the axial tensile stress in cables is much less than the ultimate tensile strength. The cost of anchor system is only 1.875% of that of the wind turbine construction.