张力腿式浮动风力机极限载荷分析

Extreme load analysis for a TLP-type floating wind turbine under operating conditions

针对所提出的新型多立柱张力腿式浮动风力机在正常工作工况下的运行,进行了时域耦合动力响应仿真分析和极限载荷预报.选取了在此工况下可能出现极值的叶片根部弯矩(面内弯矩和面外弯矩)作为研究对象,依据IEC61400-1和IEC61400-3标准要求,运用极限载荷统计外推法得到了不同重现期内的极限载荷.采用将分块最大值法和过阈最大值法相结合的方法来提取局部最大载荷.选用三参数威布尔分布作为局部最大载荷概率分布函数,并使用最小二乘法对其进行参数估计,验证了在不同风速下所拟合的极限载荷短期分布的收敛性.

Time domain coupled dynamic simulation and extreme load prediction were carried out for the proposed multi-column TLP（tension-leg-type）floating wind turbine under operating conditions.The blade root in-plane and out-of-plane bending moment were shown maximum responses during these conditions and which were selected to perform load extrapolation analysis,based on the requirements of IEC61400-1and IEC61400-3.The long-term extreme loads with different return periods were thus obtained.Local extremes were extracted by using the method integrated time separation and peak-over-threshold method.The three parameters Weibull distribution was chosen to fit the local extremes.Distribution parameters were estimated by least square method.A convergence test was examined for the fitted distributions of different wind speeds.