风力机叶片是风力机的关键部件,为了解决叶片受到阵风或随机风作用后振动衰减缓慢、叶片产生较大空间扭曲变形等问题,在叶片中嵌入压电材料,运用变分法、哈密顿(Hamilton)原理和扁壳理论,建立了压电板壳式复合材料叶片结构的机-电耦合动力学数学模型,并应用MATLAB软件对叶片在施加控制电压前后的响应特征进行了数值求解,根据计算结果分析了叶片各方向位移、转角随时间的变化和风载作用下控制电压对叶片振动的抑制情况.分析结果表明:施加控制电压前,叶片在受到阵风或随机风作用后,振动衰减缓慢,在给叶片中压电材料施加控制电压后,在压电材料的逆压电效应下,叶片的振动衰减迅速,在极端风速情况下能极大地提高风力机叶片的气动弹性稳定性.因此,采用压电材料,利用其逆压电效应,根据风载施加控制电压,能够有效抑制极端风载作用下叶片的振动,从而提高其服役周期.%The blade is the key part of wind turbine, in order to solve the problems of slow vibration attenuation and large distortion of blade when the blade is subjected to gust or random wind, the piezoelectric material was embedded in the blade, and the variational method, Hamilton principle and shell theory were used. The electro-mechanical coupling dynamics model of wind turbine blade of composite shell was conducted, and the response characteristics of blade before and after applying the control voltage were calculated by using MATLAB software. According to the calculation results, the change of the displacement and angle of the blade with time and the suppression of the blade vibration by the control voltage under the wind load were analyzed. The results showed that the vibration of blade under gust wind or random wind attenuated slowly before applying voltage, but, when the control voltage was applied to piezoelectric material on the blade, the vibration of blade attenuated quickly because of the reverse piezoelectric effect of piezoelectric material, which could improve aeroelastic stability of the wind turbine blade great in extreme wind conditions. Therefore, the piezoelectric material can be used to suppress the vibration of blade under extreme wind load by using its converse piezoelectric effect and applying control voltage according to wind load so as to improve service life of wind turbine blade.
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