谐波干扰下海上风机结构工作模态识别

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振动与冲击 ›› 2015, Vol. 34 ›› Issue (10) : 152-156.

论文

谐波干扰下海上风机结构工作模态识别

董霄峰，练继建，杨敏，王海军

作者信息 +

Operational modal identification of offshore wind turbine structure considering the harmonic interference

DONG Xiao-feng，LIAN Ji-jian，YANG Min，WANG Hai-jun

Author information +

文章历史 +

摘要

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。

Abstract

With the high rotating speed of blades, it is more difficult to identify the operational modal parameters of the offshore wind turbine structure accurately because the structural modal information of responses usually buried in the period components induced by the strong recurring harmonic excitation. In order to solve the problem of structural operational modal identification, a method, combined the modified eigensystem realization algorithm (ERA) with probability density function (PDF), was implemented in this paper. Subsequently, the interference resulted from the rotating frequencies and frequency multiplication was eliminated and the effective identification on the multi-operational modal parameters of one offshore wind turbine experimental prototype was also achieved based on the measured signals under different operational conditions. This approach can not only avoids the strong harmonic interference so as to obtain the real structural operational modes effectively, but also has a better engineering applicability on the online real-time monitoring and evaluation of the structural operational security for the offshore wind turbine structure.

导出引用

董霄峰，练继建，杨敏，王海军. 谐波干扰下海上风机结构工作模态识别[J]. 振动与冲击, 2015, 34(10): 152-156

DONG Xiao-feng，LIAN Ji-jian，YANG Min，WANG Hai-jun. Operational modal identification of offshore wind turbine structure considering the harmonic interference[J]. Journal of Vibration and Shock, 2015, 34(10): 152-156

参考文献

[1] Carne T G,James G H. The inception of OMA in the development of modal testing technology for wind turbines[J]. Mechanical Systems and Signal Processing,2010,24:1213- 1226.
[2] Hansen M H, Thomsen K, Fuglsang P,et al. Two methods for estimating aeroelastic damping of operational wind turbine modes from experiments [J]. Wind Energy,2006, 9: 179-191.
[3] Peeters B,Cornelis B,Janssens K. Removing disturbing harmonics in operational modal analysis[C]. In Proc. IOMAC,Copenhagen Denmark,2007.
[4] Jacobsen N J, Andersen P, Brincker R. Eliminating the influence of harmonic components in operational modal analysis [C]. IMAC XXV Conference, 2007.
[5] 张义民,张守元,李鹤,等.运行模态分析中固有模态和谐波模态区分方法研究[J].振动与冲击,2009, 28(1):64-67.
   ZHANG Yi-min, ZHANG Shou-yuan,LI He,et al. Study on method of distinguishing the natural modes from harmonic modes in operational modal analysis[J]. Journal of Vibration and Shock, 2009, 28(1):64-67.
[6] Brincker R, Andersen P, Møller N. An indicator for separation of structural and harmonic modes in output-only modal testing[C]. International Modal Analysis Conference (IMAC XVIII), San Antonio, TX, Society for Engineering Mechanics, Bethel, CT, 2000: 1649-1654.
[7] Mohanty P,Rixen D J. Identifying mode shapes and modal frequencies by operational modal analysis in the presence of harmonic excitation [J].Society for Experimental Mechanics, 2005, 45(3): 213-220.
[8] Mohanty P,Rixen D J. Modified SSTD method to account for harmonic excitations during operational modal analysis[J]. Mechanism and Machine Theory, 2004, 39: 1247-1255.
[9] 练继建,李火坤,张建伟. 基于奇异熵定阶降噪的水工结构振动模态ERA识别方法[J].中国科学E辑,2008,38(9):1398- 1413.
    LIAN Ji-jian, LI Huo-kun, ZHANG Jian-wei. ERA modal identification method for hydraulic structures based on order determination and noise reduction of singular entropy[J]. Science in China Series E: Technological Sciences, 2008, 38(9): 1398-1413.
[10] Li P, Hu S L J, Li H J. Noise Issues of modal identification using eigensystem realization algorithm[J]. Procedia Engineering, 2011, 14:1681-1689.
[11] Mohanty P,Rixen D J. Modified ERA method for operational modal analysis in the presence of harmonic excitations[J]. Mechanical Systems and Signal Processing, 2006, 20:114- 130.
[12] 李怀鹏.运行模态分析中周期性激励识别方法研究[D].南京：南京航空航天大学，2010.
[13] Lian Ji-jian, Sun Li-qiang, Zhang Jin-feng et al. Bearing capacity and technical advantages of composite bucket foundation of offshore wind turbines [J]. Transactions of Tianjin University, 2011, 17: 132-137.
[14] Lian Ji-jian, Ding Hong-yan, Zhang Pu-yang,et al. Design of large-scale prestressing bucket foundation for offshore wind turbines[J].Transactions of Tianjin University,2012,18:79- 84.
[15] 练继建,张建伟,李火坤,等. 泄洪激励下高拱坝模态参数识别研究[J].振动与冲击,2007, 26(12):101-105.
    LIAN Ji-jian, ZHANG Jian-wei, Li Huo-kun,et al. Study on modal parameter identification of high arch dam under flood discharge excitation[J]. Journal of Vibration and Shock, 2007, 26(12):101-105.