【作者】 宋来收；

【导师】 夏品奇；

【作者基本信息】 南京航空航天大学 ， 飞行器设计， 2013， 博士

【摘要】 直升机的高振动水平会严重影响直升机的飞行性能和飞行安全，降低直升机振动水平一直是直升机技术领域期待解决的难题。结构响应主动控制具有控制效果好、适应性强等优点，已成为直升机振动控制的最重要发展方向。直升机结构响应主动控制的核心是准确的机体结构/作动器耦合动力学模型、高性能的控制器和作动器，要求控制器具有快速、自适应的控制能力，要求作动器质量轻、输出力大、工作频带宽、响应速度快。本文根据直升机机身振动的稳态谐波特性、压电叠层作动器的驱动特性及直升机振动主动控制要求，深入研究了压电叠层作动器驱动的直升机结构响应自适应控制，有效克服了现有直升机振动主动控制中采用惯性作动器及由于控制器性能差所带来的附加重量大、工作频带窄、控制速度慢、适应性差等缺点，为有效提高振动主动控制系统的性能、有效降低直升机振动水平建立了新的直升机结构响应自适应控制方法。本文研究取得的创新点主要有以下四个方面：（1）建立了直升机结构响应主动控制的机身/压电叠层作动器复合结构的耦合优化法，研究了压电叠层作动器安装对机身结构特性的影响，为直升机振动主动控制中建立准确的机体结构/作动器耦合动力学模型奠定了理论基础。通过建立直升机机身/压电叠层作动器复合结构的耦合频域方程及改进实数编码遗传算法，实现了同时优化作动器安装位置离散变量和控制器加权参数连续变量的混合优化，得到了在控制输入约束下的最有效振动控制。该耦合优化法与目前国际上把压电叠层作动器理想成力发生器的方法相比，得到的优化结果具有更好的振动控制效果。（2）建立了直升机结构响应自适应控制的谐波同步识别-修正法，克服了现有直升机结构响应主动控制的频域法中信号时/频转换采用离散傅里叶变换及其逆变换所带来的缺点，为直升机振动主动控制系统中构建高性能的控制器奠定了理论基础。采用递推最小二乘算法和基于最陡梯度法的自适应谐波控制，实现了直升机结构响应自适应控制中控制误差响应谐波系数识别与控制输入谐波系数同步修正。基于作动器安装位置和控制器参数的优化结果，采用稳态谐波激励及幅值快速周期时变谐波激励研究了压电叠层作动器驱动的机身弹性线梁模型的多输入/多输出结构响应自适应控制，结果表明建立的直升机结构响应自适应控制的谐波同步识别-修正法能有效降低直升机的振动水平，且具有较强的自适应控制能力。（3）把建立的直升机结构响应自适应控制的谐波同步识别-修正法用于控制器，建立了具有自适应控制能力的结构响应控制实验系统。把直升机机身结构模拟为自由-自由弹性梁，采用压电叠层作动器驱动梁模型，以控制点的加速度响应为控制目标，对由激振器模拟旋翼激励梁模型产生的稳态谐波振动和实测的某直升机机身振动进行了自适应控制的理论和实验研究，结果表明具有由谐波同步识别-修正法的控制器和由压电叠层作动器驱动的结构响应自适应控制系统能有效降低结构的振动水平，且具有较强的自适应控制能力。（4）建立了结构响应自适应控制中压电叠层作动器迟滞非线性的谐波输入补偿法，解决了压电叠层作动器迟滞非线性对结构振动控制的影响问题，为直升机振动主动控制系统中构建高性能的作动器奠定了理论基础。基于控制通道传递函数矩阵的下三角特性，对单频、多频振动控制证明了压电叠层作动器驱动的振动自适应控制系统的收敛性并给出了收敛条件，并证明了在存在压电叠层作动器的迟滞非线性时，线性谐波控制与线性控制通道具有相同的收敛性质。通过对压电叠层作动器迟滞非线性影响的理论与实验研究，表明了该谐波输入补偿法的有效性。更多还原

【Abstract】 The high vibration levels of helicopter will seriously affect the flight performanceand the flight safety of helicopter. To effectively reduce the vibration levels of helicopterhas been the difficult problem in the field of helicopter technology which has beenexpected to solve. Active control of structural response has the advantages such as thegood control effect and strong adaptability etc., and has become the most importantdevelopment direction in helicopter vibration control. The cores of active control ofhelicopter structural response are the accurate fuselage structure/actuator couplingdynamic model, high-performance controller and actuator, requiring the controller hasthe rapid and adaptive control ability, actuator has light weight, large output force, wideworking frequency range and fast response speed. Based on the steady harmoniccharacteristics of helicopter fuselage vibration, the driving characteristics of piezoelectricstack actuators and the requirements of active vibration control of helicopter, the adaptivecontrol of helicopter structural response driven by piezoelectric stack actuators has beendeeply investigated in this thesis, and has effectively overcome the shortcomings such asthe large additional weight, the narrow range of working frequency, slow speed of control,poor adaptability etc. brought by using the inertial actuator and the controller with poorperformance in the existing active vibration control of helicopter, establishing a newmethod for adaptive control of helicopter structural response to effectively improve theperformance of active vibration control system and to effectively reduce the vibrationlevels of helicopter. This investigation has made major innovation of the following fourareas:(1) A coupling optimization method of fuselage/piezoelectric stack actuatorscomposite structure for active control of helicopter structural response has beenestablished, to solve the effect problems of installation of piezoelectric stack actuators onthe structural characteristics of fuselage and to lay a theoretical foundation forestablishing an accurate dynamic model of fuselage structure/actuators couplingstructure in the active vibration control of helicopter. Through the establishment of thecoupling frequency-domain equations of helicopter fuselage/piezoelectric stack actuators coupled composite structure and improvement of real-coded genetic algorithm,the hybrid optimization of simultaneously optimizing the discrete variables of theactuator installed positions and the continuous variables of the weighted parameters ofcontroller was achieved and the most effective vibration control was obtained in theconstraints of control input. Comparing with the current method in the world which thepiezoelectric stack actuator was idealized as a force generator, the coupling optimizationmethod can obtain the optimal results with better vibration control effect.(2) A harmonic synchronous identification-updating method for adaptive control ofhelicopter structural response has been established, to overcome the drawbacks broughtby using the discrete Fourier transform and its inverse transform for time/frequencyconversion of signals in the existing frequency-domain method in the active control ofhelicopter structural response, and lay a theoretical foundation for building thehigh-performance controller in the active vibration control system of helicopter. Usingthe recursive least squares algorithm and the steepest gradient method based adaptiveharmonic control, the identification of control error response harmonic coefficients andsynchronous updating of control input harmonic coefficients in the adaptive control ofhelicopter structural response were achieved. Based on the optimization results ofactuator installed positions and the parameters of controller, the adaptive control ofmultiple input/multiple output responses of a fuselage elastic beam model driven bypiezoelectric stack actuators by using the steady harmonic excitation and the harmonicexcitation with fast cycle time-varying amplitude has been investigated. The resultsindicated that the established harmonic synchronous identification-updating method foradaptive control of helicopter structural response could effectively reduce the vibrationlevels of helicopter, and had strong adaptive control ability.(3) An experimental control system of structural response with adaptive controlability has been set up by using the established harmonic synchronousidentification-updating method in the controller for adaptive control of helicopterstructural response. The helicopter fuselage structure was simulated a free-free elasticbeam. Using piezoelectric stack actuators to drive the beam model, taking theacceleration responses at the control points as the control objectives, the theoretical andexperimental investigations on adaptive control of the steady harmonic vibrationgenerated by the exciter simulating rotor to excite the beam and the vibration measured in a helicopter fuselage have been carried out. The results indicated that the system ofadaptive control of structural response with the controller made by the harmonicsynchronous identification-updating method and driven by piezoelectric stack actuatorscould effectively reduce the vibration level of structure, and had strong adaptive controlability.(4) A harmonic input compensation method for the hysteresis nonlinearity ofpiezoelectric stack actuator in adaptive control of structural response has been established,to solve the effect of hysteresis nonlinearity of piezoelectric stack actuator on thevibration control of structure, and to lay a theoretical foundation for building thehigh-performance actuator in the system of active vibration control of helicopter. Basedon the lower triangular characteristics of transfer function matrix of control channel, forthe single-frequency, multi-frequency vibration control, the convergence of adaptivevibration control system driven by piezoelectric stack actuator was proved and theconvergence conditions were given, and it was proved that in the presence of hysteresisnonlinearity of piezoelectric stack actuator, the linear harmonic control and the linearcontrol channel have the same convergence properties. The theoretical and experimentalstudies on the effect of hysteresis nonlinearity of piezoelectric stack actuator verified theeffectiveness of the harmonic input compensation method.更多还原