CAJ | 학술논문

针对海上风力发电机组高转速叶轮对风机结构会造成强烈的周期性激励，而该强谐波作用往往会淹没响应中的结构模态信息，增加识别结构工作模态参数难度问题，以某海上风电试验样机振动响应原型观测信号为研究对象，采用基于改进特征系统实现法（Eigensystem Realization Algorithm，ERA）与概率密度函数法（Probability Density Function， PDF）结合的工作模态识别方法及判定思路，剔除不同工况下转频、倍频谐波成分干扰，实现风机结构多阶工作模态参数有效识别。该方法不仅能有效避免谐波干扰以获取结构的真实工作模态，同时对海上风机结构运行安全性实时在线监测、评估具有较好的工程适用性。
침대해상풍력발전궤조고전속협륜대풍궤결구회조성강렬적주기성격려，이해강해파작용왕왕회엄몰향응중적결구모태신식，증가식별결구공작모태삼수난도문제，이모해상풍전시험양궤진동향응원형관측신호위연구대상，채용기우개진특정계통실현법（Eigensystem Realization Algorithm，ERA）여개솔밀도함수법（Probability Density Function， PDF）결합적공작모태식별방법급판정사로，척제불동공황하전빈、배빈해파성분간우，실현풍궤결구다계공작모태삼수유효식별。해방법불부능유효피면해파간우이획취결구적진실공작모태，동시대해상풍궤결구운행안전성실시재선감측、평고구유교호적공정괄용성。
It is difficult to identify the operational modal parameters of an offshore wind turbine structure accurately because the structural modal information in its responses is buried by the strong recurring harmonic excitation induced from the wind turbine's impeller with high rotating speed.In order to solve the problem of structural operational modal identification,a method combining the modified eigensystem realization algorithm (ERA)with the probability density function (PDF)was proposed here.Subsequently,the interference coming from the rotating frequencies and frequency multiplication was eliminated and the effective identification for the multi-operational modal parameters of a certain offshore wind turbine test prototype was achieved based on the measured signals under different operational conditions.It was shown that this approach can not only avoid the strong harmonic interference so as to obtain the real structural operational modes effectively,but also has a better engineering applicability in online real-time monitoring and evaluation of the structural operational security for offshore wind turbine structures.