地震对不同容量风力机塔架动力响应规律研究

Research on Dynamic Response for Different Capacity Wind Turbine Tower under Earthquake

为研究湍流风与地震联合作用下风力机塔架动力响应规律,以AOC 50 kW、WindPACT 1.5 MW和NREL 5 MW 3种不同容量风力机为研究对象,考虑土-构耦合模型效应,基于开源软件FAST预留数据接口,编译地震载荷计算模块,建立了湍流风与地震激励实时耦合的动力仿真模型。基于ASCE标准地震反应谱,得到20种不同强度的地震加速度,计算了不同强度地震与湍流风联合作用下的风力机塔架动力学响应。结果表明:地面加速度峰值(Peak Ground Acceleration,PGA)为0.3g时,湍流风与地震联合作用对塔基剪切力和弯矩影响较大;随地震强度的增大,塔架不同高度处的最大弯矩与高度之间的关系逐渐由线性转变为非线性;发现国际电工委员会(International Electrotechnical Commission,IEC)和美国风能协会/美国土木工程师协会(American Wind Energy Association/The American Society of Civil Engineers,AWEA/ASCE)对地震载荷与风载荷共同作用下的载荷预估模型结果误差较大,并提出了新的高精度模型,可为风力机塔架载荷预估及预防地震风险提供一定的参考。

For the analysis on dynamic behavior law of wind turbine,the AOC 50 kW,WindPACT 1.5 MW and NREL 5 MW wind turbines under turbulence and earthquake are selected as the subjects of study.The soil-structure interaction is considered.Based on the interface of open-sourced software FAST,a seismic module was compiled to evaluate the seismic load of wind turbine.The simulation model for the wind coupled with earthquake is built up.Based on the standard response spectrum defined by American Society of Civil Engineers(ASCE),twenty different seismic accelerations are obtained to investigate the dynamic response of wind turbine tower under different combined conditions of turbulence and earthquake.The results show that the coupled condition of turbulence and earthquake affects the bending moment and shear force significantly when the peak ground acceleration(PGA)is 0.3g.With the increase of earthquake intensity,the relationship between the peak of tower bending moment and tower height becomes nonlinear from linear.Furthermore,the methods of evaluating the tower load provided by International Electrotechnical Commission(IEC)and American Wind Energy Association/American Society of Civil Engineers(AWEA/ASCE)cannot estimate seismic load effectively.The new nonlinear methods proposed in this paper are more accurate.These findings can provide reference for estimating tower load and preventing the seismic risk for wind turbines.