基于高阶统计量的海上风电单桩支撑结构损伤监测研究

Monopile support structures of offshore wind power are high and flexible, and the nonlinear vibration characteristics under random load are obvious. As more and more offshore wind turbines have been put into operation, the performance degradation and health monitoring of monopile support structures in complex marine environment have attracted great attention. A precise numerical simulation model of wind power structures is established. The evolution law of dynamic characteristics of monopile support structures and the influence of typical damage on the dynamic responses are studied by using this precise numerical simulation model. The layout of monitoring sensors is optimized, and the software of monitoring system is developed for managing massive monitoring data. Aiming at multi-source vibration signals, a damage monitoring method based on high order statistics and a damage inversion method based on sample clustering are proposed. A robust health monitoring index of monopile support structures of offshore wind turbines is put forward based on the stationarity test theory for dynamic system. A cooperative analysis method is further proposed to analyze the safety in the view of the whole wind farm. Finally, the project establishes a set of safety assessment technology for monopile support structures of offshore wind power by the integration of numerical model, theoretical method and test system above-mentioned. The results are helpful to improve the damage warning ability and safety management level for wind power structures, and can also promote interdisciplinary with important theoretical significance and engineering application prospect.

海上风电单桩支撑结构高度大、柔度大，在随机荷载作用下非线性振动特征明显。随着越来越多海上风电建成投产，单桩支撑结构在复杂海洋环境下的性能劣化和健康监测日益引起关注。通过建立海上风电单桩支撑结构的精细化数值模型，掌握支撑结构的动力特性演变规律，揭示典型损伤缺陷对支撑结构动力响应的影响。开展监测点优化布置，开发监测系统软件，实现海量监测数据的可靠采集和管理。针对多源混叠振动信号，提出基于高阶统计量的风机单桩支撑结构损伤监测方法，提出基于样本聚类的损伤反演方法。基于动态系统的平稳性检验理论，提出海上风电单桩支撑结构的健康监控指标，实现风电场多台风机监测数据的协同分析。通过对上述数值模型、理论方法和测试系统的集成，建立一套海上风电单桩支撑结构安全评估技术。成果有助于提高海上风电单桩支撑结构损伤预警能力，提高风电结构安全管理水平，并促进学科交叉，具有重要的理论意义和广阔应用前景。

海上风电单桩支撑结构高度大、柔度大，在随机荷载作用下非线性振动特征明显。随着越来越多海上风电建成投产，单桩支撑结构在复杂海洋环境下的性能劣化和健康监测日益引起关注。本项目主要研究内容和成果包括：建立海上风电单桩支撑结构的精细化数值模型，开展风电结构振动响应特征及演变规律研究，掌握基础刚度弱化对海上风电结构动力响应的影响。研究风电结构不同部件的疲劳累积损伤机制，研究掌握气动阻尼比取值、风浪耦合等对基础疲劳损伤的影响，提出基于概率密度演化的风机结构疲劳概率计算方法。开展多源混叠振动信号分离方法研究，开发基于高阶统计量的振动信号隐含信息识别算法与结构损伤识别方法，提高强背景噪声中识别弱故障信号的能力。开展监测点优化布置，开发监测系统软件，实现海量监测数据的可靠采集和管理。通过对上述数值模型、理论方法和测试系统的集成，建立了一套海上风电单桩支撑结构安全评估技术。项目发表论文18篇，授权发明专利2项，获软件著作权3项。成果有助于提高海上风电单桩支撑结构损伤识别与预警能力，提高风电结构安全管理水平，并促进学科交叉，具有理论意义和应用前景。