一近海风力机结构响应分析的改进预报方法

An Improved Prediction Method for Structural Response Analysis of Offshore Wind Turbines

为了克服传统的罗森布拉特IFORM(反一阶可靠性法)环境轮廓法的缺点,提出用主成分分析-反一阶可靠性轮廓法来生成更精确的环境轮廓。比较使用主成分分析-反一阶可靠性轮廓法和用罗森布拉特IFORM环境轮廓法获得的一选定近海地点的环境轮廓,以验证主成分分析-反一阶可靠性轮廓法的精度和有效性。接着基于主成分分析-反一阶可靠性轮廓法或罗森布拉特IFORM环境轮廓法得到的最高非线性海况计算一安装在这一选定近海地点的单桩支持型5 MW近海风力机的50年极端结构动力响应。系统地分析和比较计算结果,突出强调利用更符合实际的环境轮廓(如用主成分分析-反一阶可靠性轮廓法所生成的)的必要性和重要性。

In order to overcome the shortcomings of the traditional Rosenblatt-IFORM(Inverse-First-Order Reliability Method)environmental contour method,the use of the PCA(Principal Component Analysis)-IFORM contour method is proposed for generating more accurate environmental contours.The environmental contours at a chosen offshore site obtained by using the PCA-IFORM contour method are compared with those obtained by using the Rosenblatt-IFORM environmental contour method,and the accuracy and effectiveness of the PCA-IFORM contour method are convincingly vali-dated.The 50-year extreme structural dynamic responses of a monopile-supported 5 MW offshore wind turbine installed at this chosen offshore site are calculated based on the highest nonlinear sea state from the PCA-IFORM contour method(or the traditional Rosenblatt-IFORM environmental con-tour method).The calculation results are systematically analyzed and compared,and the necessity and importance of using more realistic environmental contours(such as those generated using the PCA-IF-ORM contour method)are finally highlighted.