【作者】 李洪超；

【导师】 史忠科；

【作者基本信息】 西北工业大学 ， 系统工程， 2006， 博士

【摘要】 气动伺服弹性(ASE)涉及了空气动力、惯性力、结构力、敏感元件、执行机构以及飞行控制系统之间的相互作用，它们之间的相互作用可能会造成整个飞机系统的不稳定。因此，对飞机进行气动伺服弹性稳定性分析研究，已经作为现代飞机设计、试验及试飞过程中必不可少的一项重要工作。本文结合现代多回路系统的稳定性分析理论和现代信号处理工具，主要研究了直接由飞行试验数据分析多回路气动伺服弹性系统稳定性的方法，其中的研究成果已成功应用于某型飞机多回路气动伺服弹性系统的分析，并产生了显著的军事和经济效益。其主要内容如下：1．设计并实现了采用扫频信号作为舵指令输入，确定飞机多回路气动伺服弹性系统稳定性的具体飞行试验方案，使得直接由飞行试验数据确定飞机气动伺服弹性稳定裕度成为可能；2．为克服飞行试验数据中噪声对稳定性分析的影响，首先提出了一种针对扫频激励的小波时频域去噪的方法，在时频域实现了信噪分离，显著提高了飞行试验数据的信噪比；3．在具体试验方案的基础上，提出了基于闭环系统回差矩阵最小奇异值理论的稳定性分析方法。该方法采用闭环系统回差矩阵的最小奇异值表示稳定程度。为便于工程描述，同时给出了最小奇异值与经典的幅值—相角裕度之间的对应关系；4．为克服回差矩阵方法的保守性，又提出了基于结构奇异值μ理论的多回路气动伺服弹性系统稳定裕度的确定方法。同时分析了用μ方法得到的多回路鲁棒稳定裕度与经典的幅值—相角裕度之间的对应关系，给出了多回路系统的μ值与幅值—相角裕度的对应关系图；5．设计并实现了飞机多回路气动伺服弹性系统稳定裕度的数据分析系统。该系统已通过实际飞行试验数据的测试，分析结果表明系统具有较强的可靠性和实用性。最后将本文提出的飞行试验方法应用于某型飞机气动伺服弹性系统稳定性分析，结合飞行试验数据，比较了经典的稳定裕度分析方法(Bode图)、闭环系统回差矩阵最小奇异值稳定裕度分析法和鲁棒μ方法稳定裕度分析法的分析结果，并对分析结果进行了具体说明。结果表明：本文提出的方法可以给出飞机多回路气动伺服弹性系统稳定裕度的满意结果，同时上述方法也可以用于飞行控制系统稳定裕度的分析。因此，本文的研究成果对于高性能飞机的设计和试验鉴定具有重要意义。更多还原

【Abstract】 Aeroservoelasticity (ASE) considers the interaction betweenaerodynamics,inertial,structural, actuation, sensing ,and control system.Theclosed-loop interaction of these elements may cause aircraft instabilities. Thus,aeroservoelastic stability analysis is an importance work for new aircraft designs andflight test. For this reason, some new methods based on advanced multi-loop systemstability analysis and advanced signal processing tools are presented to meet thedemand of new aircraft flight testing. The research results are applied to new aircraftASE stability analysis, and achieve great military and economy benefit. The mainresults of this thesis are described as follows:1. A detailed scheme for ASE flight testing is designed firstly, which uses the sweepsignal as command to actuator. Finally, a flight test to evaluate the ASE stability isaccomplished.2. A time-frequency filtering method based on Morlet wavelet is proposed to separatethe noise form flight data, which can reduce the effects of noise and provide a moreaccurate analysis result.3. The return difference matrix (RDM) method is investigated, which evaluates thestability margin of aeroservoelastic system by determining the minimum singularvalue of the system return difference matrix. And the relationship between singularvalue and classical gain and phase margins are given for tesing engineer.4. In order to overcome the conservativeness, a new method based on robustμanalysis is presented to evaluate the stability margin of multiloop aeroservoelasticsystem from flight test data. And the relationship betweenμand classical gainand phase margins is discussed in this paper, the evaluation diagram ofμand classical gain and phase margins for stability margins analysis is given.5. An ASE data processing system is constructed and validated by real flight testing data, thefinal results show effectiveness and efficiency of the system.Finally, the return difference matrix method and robustμmethod combined withtime-frequency filter are validated by real flight testing data, and the results arecompared with classical stability margin analysis method for single input single output(SISO) system, a detailed discussion is given.The results illustrate that these method presented in this paper can be used toobtain satisfied stability margin during flight for multiloop aeroservoelastic system.Also, These methods can used to analyse stability margins of MIMO control system.Thus these methods for system stability margin analysis play important role in moderncombat aircrafts design and test.更多还原