海上风力发电机组单桩基础侧向位移估计研究

Research on Lateral Displacement Estimationof Monopile Foundation for Offshore Wind Turbines

常规海上风力发电机组单桩基础侧向位移估计模型的构建多采用粒子群优化算法。但该算法无法准确计算出海水与单桩基础之间的耦合力,估计准确率较低。对此,提出海上风力发电机组单桩基础侧向位移估计研究。首先,根据海上风力发电机组与连接单桩基础的基本结构,将单桩基础结构进行断面划分,建立单桩基础结构动力学方程。然后,结合海水域、桩基区域和两者交界处这三个场域,求取海水与单桩基础之间的耦合力,并计算单桩基础的受力值。基于此,采用风力和海浪循环荷载作用下单桩基础的累积应变指数型经验式,构建单桩基础侧向位移估计模型。以某海域NREL 5 MW单桩基础海上风力发电机组为算例,对所提模型进行仿真对比试验。试验结果表明,所构建的模型具有更高的估计准确率,即准确率在98%以上。该模型能够更好地监测和评估海上风力发电机组的结构安全性,及时发现潜在的问题并进行修复或维护。

The construction of the lateral displacement estimation model of monopile foundation for conventional offshore wind turbines mostly adopt particle swarm optimization algorithm.However,this algorithm cannot accurately calculate the coupling force between seawater and monopile foundation,and the estimation accuracy is low.In this regard,the lateral displacement estimation research of monopile foundation for offshore wind turbines is proposed.Firstly,according to the basic structure of offshore wind turbines and connecting monopile foundation,the monopile foundation structure is divided into sections,and the monopile foundation structure dynamics equation is established.Then,the coupling force between seawater and monopile foundation is obtained by combining the three fields of seawater area,monopile foundation area and the junction of the two,and the force value of monopile foundation is calculated.Based on this,the cumulative strain exponential type empirical formula of monopile foundation under wind and wave cyclic loading is used to construct the lateral displacement estimation model of monopile foundation.The NREL 5 MW monopile foundation offshore wind turbines in a sea area is used as an example for simulation and comparison tests of the proposed model.The test results show that the constructed model has a higher estimation accuracy,i.e.,the accuracy is above 98%.The model can better monitor and evaluate the structural safety of offshore wind turbines,and to detect potential problems and repair or maintain in time.