【作者】 姚照辉；

【导师】 鲍文；

【作者基本信息】 哈尔滨工业大学 ， 动力机械及工程， 2010， 博士

【摘要】 采用超燃冲压发动机推进的吸气式高超声速飞行器在可预见的未来空天运输和军事领域具有强烈的应用前景。吸气式高超声速推进系统即超燃冲压发动机面临很多关键技术亟待突破,目前美国、俄罗斯、欧洲、澳大利亚、日本等军事大国和组织都投入巨大的人力、物力和财力加紧进行攻关研究,尤其美国、俄罗斯等国已进入飞行试验阶段。为缩小我国在国防尖端技术领域与其他军事强国之间的差距,占据未来吸气式高超声速推进技术的制高点,有必要对该领域的相关关键技术难题进行探索和研究。本文针对高超声速飞行器机身/超燃冲压发动机一体化耦合建模与控制方面面临的挑战,对一些关键技术难题作了研究。首先,开展了高超声速飞行器机身/超燃冲压发动机一体化建模研究。针对高超声速飞行器机身/超燃冲压发动机一体化控制设计对建模提出的要求,采用特性分析、CFD计算、试验数据验证、数据拟合等多种方法,建立了含安全边界的高超声速飞行器机身/超燃冲压发动机耦合模型HIT-HAV。其中重点探讨了对各种安全边界的建模过程。最终建立高超声速飞行器机身/超燃冲压发动机耦合模型HIT-HAV不仅可以输出各种飞行状态,还包含超燃冲压发动机各个截面的气动参数、推力及各种安全边界。最后对所建立的模型进行了比较分析和验证。其次,分析了高超声速飞行器存在的特殊耦合特性。基于已建立的含安全边界的高超声速飞行器机身/超燃冲压发动机耦合模型HIT-HAV,分析了气动力/推力耦合特性对飞行动力学的影响;然后通过仿真分析了高超声速飞行器机身与超燃冲压发动机之间存在的耦合作用,以及耦合作用对机身及超燃冲压发动机在运行过程中的各种安全边界的影响;然后基于耦合特性对模型结构带来的影响以及传统飞行控制面临的挑战,分析阐述了进行高超声速飞行器机身/超燃冲压发动机一体化控制的必要性,并指出在一体化控制框架下的超燃冲压发动机切换控制必要性。接下来,开展超燃冲压发动机的性能调节/安全保护切换控制设计方法研究。针对高超声速飞行控制及超燃冲压发动机控制中普遍存在的多控制器切换问题,描述了一种基于Min/Max规则的调节/保护切换控制系统,给出了在Min切换规则下切换子系统的稳定性条件。分析了切换的必要条件即积分饱和受限的作用及其对切换快速性的影响。分析了切换系统依赖于初始状态的动态响应过程并在初始状态参数空间里求出了最大百分比超调量的最大值,定义其为闭环切换系统的一种保守动态性能。接下来给出了面向动态性能指标的切换控制系统一般设计方法,最后在超燃冲压发动机模型及高超声速飞行器耦合模型HIT-HAV上进行了仿真试验,验证了该切换控制方法的有效性。最后,探讨了进行高超声速飞行器全新飞/推协调控制的方案。基于尽量降低设计难度和节约成本的考虑,提出了一种基于安全裕度的高超声速飞行器飞/推协调控制方法。其基本思想是:在不改变原有飞行器控制系统和发动机控制系统结构的前提下,引入了一种基于飞行器和发动机安全裕度的动态协调因子,用动态协调因子来引导各个控制器改变控制信号对当前的工作状态进行控制。由于安全裕度表征了飞行器和发动机工作点距离安全运行边界的远近程度,因此通过实时检测安全裕度进而改变动态协调因子的方法,就能在飞行性能和飞行安全之间进行协调控制。最后通过一个设计实例,验证了该方法在高超声速飞行器飞/推一体化控制应用中的可行性。更多还原

【Abstract】 The scramjet-powered hypersonic air-breathing flight vehicle has a wide application background especially in space transportation and the military in the foreseeable future. And there are many key problems are urgent to be solved in hypersonic air-breathing propulsion technology. Nowadays, many military powers and organizations including the U.S., Russia, Europe, Australia, Japan, and so forth, have been engaged on this field with great human resources and financial support to conduct hypersonic air-breathing propulsion projects. And those programs in the U.S. and Russia are already under the flight test phase and will soon reach to a success. In order to reduce the gap and distance in the top defense technologies in the future between China and other great military powers, and take a place at air-breathing hypersonic propulsion technology, it is quite necessary for Chinese researchers to consider and solve some key technical problems related to the field at present.First, the model for the airframe-scramjet integrated hypersonic airbreathing flight vehicle with safety boundaries is developed. Based on the special request on the coupled flight dynamics analysis and control design for the modeling the hypersonic vehicle, the dissertation describes the overall diagram block for the hypersonic vehicle model HIT-HAV with a non-symmetrical configuration. By aerodynamics analyzing, CFD calculating, experimental data comparing, data fitting and other methods, the integrated hypersonic air-breathing flight vehicle and scramjet engine model HIT-HAV is built. The final finished model HIT-HAV can outputs any aerodynamic parameters, thrust and safety margins and is verified by comparison analysis.Next, the coupled dynamics between scramjet engine and aerodynamics is analyzed. Based on the hypersonic vehicle/ scramjet engine model HIT-HAV with safety boundaries, the impact of the integrated aerodynamics/propulsion on the flight dynamics is analyzed. The couplings between the flight vehicle and scramjet engine are revealed by model simulation. Due to the influence of the coupled dynamics on the model structure and the capacity lack in traditional control, the necessity to conduct an integrated flight/propulsion control for hypersonic air-breathing flight vehicle is discussed. Due to the multiple tasks and multiple operation modes in scramjet engine, the necessity to conduct a scramjet thrust tracking and safety protecting multiobjective switching control is discussed.Then, the research on the scramjet engine tracking/protecting switching control design problem is conducted. A tracking/protecting multiobjective switching control solution under Min/Max switching rule for flight control and engine control is presented and the basic principles are analyzed. Then the stabilization condition of the specific switching control problem is given and the stability of subsystems is proved. The function of the precondition and guarantee for effective switching, i.e., the integral saturation limiting, is analyzed. Consider the closed-loop system after switching under Min switching rule as a dynamic response with initial conditions and the output maximum percent overshoot are deducted, which are dependent on not only the system parameters and controller parameters, but also on the initial conditions at switching point. The global maximum value for the output maximum percent overshoot is deducted and solved in initial conditions space and is defined as a conservative dynamic performance for the closed-loop switched system. Then a general dynamic performance index oriented switching control design method is presented. The switching control method is verified by simulating both the simplified scramjet engine and the vehicle model HIT-HAV.Finally, the research work on the coordinated control for airframe-scramjet integraged hypersonic vehicle is carried out. Based on a consideration to reduce design difficulty and minimize expense, a hypersonic vehicle/engine coordinated control based on safety margin is presented. The basic consideration and idea of coordinated control is: under a precondition of not to change the original flight and engine control structure, a coordinated factor based on vehicle and/or engine safety margin is brought in to guide the flight controller and engine controller to fit new or different flight conditions. As the safety margin can characterize the‘distance’or‘degree’that the present operation state of the vehicle or engine is apart the unsafe state, a coordinated control between flight performance and flight safety can be realized by detecting the safety margin in time and thereby changing the coordinated factor. The simulation under the coordinated control method is conducted on the nonlinear hypersonic flight vehicle HIT-HAV and the results show a rationality and feasibility of this method.更多还原