【作者】 张晓峰；

【导师】 谈和平；

【作者基本信息】 哈尔滨工业大学 ， 能源与环保（专业学位）， 2022， 博士

【摘要】 随着航天技术的发展,各类新型航天器不断出现,航天器的性能指标要求愈加苛刻,与之对应的航天器热控技术也有了更高的要求。特别是一些科学仪器,其温度指标直接与科学仪器的性能关联在一起,因此精密控温技术已经成为提升未来航天器性能的关键技术之一。本文基于航天器高精度热控的需求,梳理了温度精密测量与精密控制的指标体系,开展了高精度的温度信号测量与处理、高稳定度的精密控温和高精度的温度梯度控制方面的研究,并应用到工程型号研制中,攻克了型号中的精密控温关键技术,通过空间在轨试验成功验证了相关技术的可靠性。针对当前航天器传统热设计多基于传热理论进行主被动的热控设计与现代控制理论应用缺乏结合,本文尝试融合热解析理论、控制理论、数值传热学及实验传热学,构建针对航天器μK级精密控温的新方法。基于控制理论,明晰精密控温方法的信号与系统,探究温度信号的时频特性;基于热解析理论,构建温控过程热量传递函数,并结合航天器热分析的热网络法揭示阻尼防护等被动热控系统的热量传递特性;研究反馈、前馈控制回路特性,针对大热源、大扰动等控温难题,基于现代控制论,研究模型预测控制的基本原理,根据航天器热控制系统的目标需求、条件约束等,发展基于MPC的优化算法,提出基于前馈-反馈结合的防控一体化精密控温方法;搭建高精度控温验证性实验装置,评估该理论体系下信号、系统、防控一体化控温方法的正确性、可行性,进行评估与验证。针对航天器高精度测温系统中的各类误差导致的精度不足现状,本文分析温度测量信号的影响机制,识别了测温方法、测温器件带来的测温偏差,探讨了影响测温分辨率的传感器噪声、电流激励噪声、电桥噪声等各类噪声机理;并针对测温偏差提出星载校准方法,针对测温系统中的噪声引入卡尔曼滤波方法,实现了在轨温度数据的高分辨率处理;研制了高分辨率的测温仪器,实现了μK级的精密测温试验。在航天器的精密控温方面,既有空间上的精度要求,又有时间上的温度稳定度要求。针对引力波探测航天器10^-5K/Hz^1/2@1m Hz～0.1Hz的温度稳定度需求,本文基于防控一体化的精密控温方法,开展了引力波航天器核心载荷舱的精密控温设计。通过对核心舱外部边界环境复杂热源扰动的闭环反馈控温,结合基于热阻尼传递函数设计的隔热组件,并采用基于热场扰动识别的前馈控制方法,设计了核心舱的精密控温方案,经仿真分析验证该方案可以达到μK级的稳定度。随后开展了核心载荷舱的试验件研制,完成了核心载荷舱真空热平衡试验,利用研制的高分辨率测温仪获取了试验数据,试验结果经分析达到了34μK@1m Hz～0.1HZ,完成了引力波探测航天器精密控温的关键技术攻关,解决了型号研制过程中的难题。针对X射线望远镜聚焦镜组温度梯度的精密控制需求,在详细分析聚焦镜组的热边界特性,镜片的非连续介质特点,聚焦镜组的径向（<0.4℃）、轴向（<1℃）、周向（<1℃）温度梯度需求的基础上,提出基于闭环主动加热器的精密控温方法;采用基于热容热阻差异设计的非均匀加热器对非线性的镜片进行差异化的主动热补偿,实现镜片间小温差控制;控温方案经过整星级的热平衡试验验证,试验结果表明聚焦镜组的各向温度梯度均满足指标要求,解决了X射线望远镜的研制中的热控问题,实现了望远镜的高灵敏度探测。面向温度场的高精度预测与智能控制需求,本文提出了一种基于空间外热流预测的智能控制方法,通过外热流的预测实现对温度场的智能控制,这种热流预测的前馈控制方法,能够有效的配置航天器的资源。基于这种控制方法,本文设计了一套展开辐射器的散热系统,根据在轨任务规划,自动完成辐射器的展开和收拢,能够大幅度降低瞬时工作仪器的温度波动和补偿功率;研制的辐射器经地面试验验证和在轨验证,解决了大功率载荷的热控问题。更多还原

【Abstract】 With the development of space technology,a variety of new types of spacecrafts are emerging,with more demanding performance,thus have higher requirements in the corresponding thermal control technologies.In particular,the temperature control precision of certain scientific instruments is directly related to their detection performance.As a result,temperature control of high precision has become one of the key technologies to improve the performance of spacecrafts in the coming future.Based on the requirements for high-precision thermal control of spacecraft,this study focuses on the classifying the budget systems for precise temperature measurement and control,and we have performed a systematic series of studies on high-precision measurement and processing of temperature signals,precise temperature control with high stability,and high-precision temperature gradient control.Furthermore,we have applied these technologies to the engineering design of some mission to overcome the critical challenges of precise temperature control.The reliability of the relevant techniques is successfully verified by in-orbit tests.Considering the fact that most of the traditional approaches to spacecraft thermal design are based on heat transfer theory for active and passive thermal control design,which fails to the combination with the application of modern control theory.This study has tried to combine the thermal analytical theory,control theory,numerical and experimental heat transfer theory,to establish a new precise temperature control method forμK-level temperature control of spacecraft.Based on the control theory,the signal and system of precise temperature control methods are clarified,and the time-frequency properties of temperature signals are explored.The heat transfer function of the temperature control process is constructed based on thermal analysis theory,and the heat network approach of spacecraft thermal analysis has been used to reveal the heat transfer properties of passive heat control systems such as damping protection.The characteristics of feedback and feedforward control circuits are studied.The basic principle of predictive control of models based on modern control theory is studied for difficulties such as large heat sources and disturbances.An MPC based optimization algorithm and a precise temperature control method combining feedforward and feedback control are proposed based on the requirements and conditions of the spacecraft thermal control system.Moreover,a high-precision experimental setup for temperature control is constructed to assess the accuracy and feasibility of the integrated temperature control approaches for signal,system and prevention control.Considering the lack of control precision due to various types of errors in the temperature measurement system,this study analyzes the mechanisms affecting the temperature measurement signal.Deviations due to temperature measurement methods and devices are identified,and noise mechanisms that affect the resolution of temperature measurements,such as sensor noise,current excitation noise,and bridge noise are discussed.The onboard calibration method is proposed and the Kalman filter method is introduced to address the bias of the temperature measurements and the noise of the temperature measurement system,enabling high-resolution processing of the on-orbit temperature data.The high-resolution temperature measuring instrument is developed,and the precision ofμK-level in temperature measuring test is realized.In precise temperature control of spacecraft,there are not only spatial accuracy requirements,but also temporal temperature stability requirements.Aiming at the temperature stability requirement of gravitational wave detection spacecraft(10^-5K/Hz^1/2@1m Hz～0.1Hz),we have carried out the precise temperature control design of the core payload module of gravitational wave spacecraft based on the precise temperature control method of integrated prevention and control.The precise temperature control scheme of the core module is designed through the closed-loop feedback temperature control of the complex heat source disturbance in the boundary of external environment of the core payload module,combined with the heat insulation component designed based on the thermal damping transfer function,and the feedforward control method based on the thermal field disturbance identification.The simulation analysis shows that the scheme can achieve the stability ofμK level.Based on the temperature control scheme,we have developed the core payload module and carried out vacuum thermal balance test of the core payload module.The high-resolution temperature measurement equipment developed is used to collect the test data.The analysis results of the thermal test shows that a precision of 34μK@1m HZ～0.1HZ has been reached,suggesting that by employing these key technologies mentioned above,the critical challenge of precise temperature control in the mission of gravitational wave detection spacecraft has been successfully overcome.Considering the requirements of precision control of the temperature gradient of the focusing mirrors set of X-ray telescope,a precision temperature control method based on closed-loop active heaters is proposed on the basis of detailed analysis of the thermal boundary characteristics of the mirrors set,the characteristics of the discontinuous medium of the mirrors,and the radial（<0.4℃）,axial（<1℃）and circumaxial（<1℃）temperature gradient requirements of the mirrors set.Non-uniform heaters based on differences in heat capacity and heat resistance are used to perform the differentiation and active thermal compensation of nonlinear mirrors,enabling simple control of small temperature difference between different mirrors.The temperature control scheme has been validated by thermal balance tests of the satellite.The test results show that the temperature gradients in all directions of the mirrors group satisfy the requirements,which solves the thermal control problem in the development of X-ray telescopes and enables high sensitivity detection of the telescopes.To meet the demands for high-precision prediction and intelligent control of the temperature field,we propose an intelligent control method based on space heat flux prediction.The intelligent control of the temperature field is achieved by the prediction of the external heat flux.This feedforward control method via heat flux prediction can be used to configure spacecraft resources efficiently.Based on this control method,a set of radiator cooling systems is designed.Depending on the on-orbit mission plan,the radiator can be automatically expanded or folded,which can greatly reduce the temperature fluctuations and compensate for the power of the instantaneous working instrument.The radiator developed has been validated by ground and in-orbit tests,and the thermal control of high power loads has been addressed.更多还原