基于应变响应功率谱传递比的海上风机工作模态识别  

A strain response power spectrum density transmissibility-based operational modal identification of offshore wind turbines

作　　者：陈志为[1] 刘奎铭 陈华书 荣维栋 刘俊 CHEN Zhiwei;LIU Kuiming;CHEN Huashu;RONG Weidong;LIU Jun(School of Architecture and Civil Engineering,Xiamen University,Xiamen 361005,China;Envision Energy Limited Company,Shanghai 200051,China)

机构地区：[1]厦门大学建筑与土木工程学院,福建厦门361005 [2]远景能源有限公司,上海200051

出　　处：《厦门大学学报（自然科学版）》2021年第4期755-761,共7页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(51778550);厦门市科技计划项目(3502Z20193020);厦门大学校长基金(20720180060)。

摘　　要：利用传递比函数与应变响应的优势,提出了基于应变响应功率谱传递比(SPSDT)的海上风机工作模态识别方法.该方法无需通过复杂的信号预处理,仅基于传递比函数识别响应信号的统计特性差异,便可有效区分结构工作模态与谐波干扰.选择某海上风机结构为应用及验证对象,首先利用风机停机状态下的加速度和应变响应识别结构模态参数,验证了应变模态分析方法的可行性.随后利用风机在工作状态下多个工况的应变数据,进一步验证了通过结合SPSDT函数可使新方法有效克服转频谐波干扰,准确稳定地识别不同工况下风机工作模态.将该方法应用于风机结构的模态识别,具有良好的发展潜力和应用前景.Taking advantages of transmissibility function and strain response,we propose a strain response power spectrum density transmissibility(SPSDT)-based model identification method for applications to offshore wind turbines.Without a signal pre-processing step that normally appears complex,the proposed method can distinguish structural working mode and harmonic interference through statistical characteristics of a transmissibility function constructed by response signals.For purposes of applications and verifications,an offshore wind turbine structure is chosen as a case study.First,the structural modal parameters are identified respectively using acceleration data and strain data in the shutdown condition of wind turbines.Results of comparisons indicate the feasibility of the method in strain modal analyses.Subsequently,further verification is completed by using strain data in various working conditions.Results show that,by combining with the SPSDT function,the proposed method is able to effectively overcome harmonic interferences and accurately and stably identify working modes of wind turbines in different conditions.Finally,the likelihood of applying the proposed method to offshore wind turbines is highly expected.

关 键 词：模态识别 谐波干扰 功率谱传递比 应变响应 海上风机 

分 类 号：TB53[理学—物理]