KMS of Xinjiang Astronomical Observatory, CAS
| 基于大口径射电望远镜指向需求的天线伺服控制算法的研究 | |
| Alternative Title | The study of antenna servo control algorithms based on high-precision pointing of large-aperture radio telescope |
李宁
| |
| Subtype | 博士 |
| Thesis Advisor | 王娜 |
| 2021-06-01 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Name | 理学博士 |
| Degree Discipline | 天文技术与方法 |
| Keyword | 射电望远镜天线 指向精度 伺服控制 扰动/不确定观测和补偿 H∞-GESO |
| Abstract | 射电望远镜天线在射电天文研究中扮演了一个重要角色。随着天文研究的深入，要求天线有更高分辨率，对更暗弱的物体进行观测。为了保证观测的有效性，需要天线有很高的角分辨率和灵敏度，因而单口径射电望远镜天线的口径越来越大，对天线指向精度的要求也越来越高。随着天线口径的增大，天线的惯量成倍增大，摩擦等非线问题和天线结构柔性问题也变得更加突出，这些问题为天线的高精度控制带来不小的挑战。本文围绕天线高精度指向控制问题，进行了如下研究：1.射电望远镜天线结构建模与分析：首先对天线伺服系统的构成进行了机理建模，指出了基于机理分析建立的模型存在的问题。继而分析了天线伺服系统中广泛存在的诸如摩擦、齿隙非线性特性以及系统结构的柔性特性。然后推导了复杂系统的模型辨识方法。进而指出真实系统与模型之间存在不确定性问题并介绍了几种典型的模型不确定性结构。最后分析了外部风载对天线伺服系统的影响。2.典型控制算法理论分析与实验：首先，研究了控制系统综合的性能指标，其次，重点分析了整数阶PID控制，回路成形控制设计，基于系统2/∞-范数的线性二次型最优调节控制(LQR)、线性二次型高斯控制(LQG)、H2、H∞控制，基于扰动观测器的控制(DOBC)，自抗扰控制(ADRC)，定量反馈控制(QFT)。结合模型的不确定性，对参数不确定对象设计了基于PID、LQG、混合灵敏度H∞、线性ADRC的实验，基于蒙特卡洛思想，考察了不确定系统的性能指标变化情况。此外，对非线性ADRC性能也进行了实验分析。3.复合控制算法设计与实验：基于典型控制算法的理论与实验分析，提出了基于回路成形和扰动/不确定观测和补偿的混合灵敏度H∞-GESO复合控制算法，其中GESO被用来观测和消除因系统不确定性和外部扰动带来的输出误差，H∞用来实现要求的系统的动态性能。继而设计相应实验，结果验证了所提方法在信号跟踪和抗扰方面的良好性能。最后，对本论文进行了总结，指出将本文提出的混合灵敏度H∞-GESO复合控制算法方法优点与不足，并讨论了后续工作。 |
| Other Abstract | Radio telescope antennas play an important role in radio astronomy research. With the deepening of astronomical research, the antenna is required to have higher resolution and be able to observe fainter objects. In order to guarantee the effectiveness of observation, the antenna needs to have higher angular resolution and sensitivity. Therefore, the diameter of single-antenna radio telescope is getting larger and larger, and the requirement for the antenna pointing accuracy is becoming higher and higher. With the increase of antenna aperture, the inertia of antenna doubles, and the nonlinear problems such as friction and the structural flexibility of the antenna become more prominent. These problems bring great challenges to the high-precision servo control of the antenna. This dissertation studies the high precision pointing control of the antenna. Main contents of this dissertation are shown as follows:1. Modeling and analysis of the antenna servo system: first, the mechanism modeling for the compositions of the antenna servo system is carried out, and the problems of the model based on mechanism analysis are pointed out. Then, the nonlinear characteristics of friction, backlash and the flexibility of the system structure, which are widely existed in the antenna servo system, are analyzed. And then the model identification method of complex system is derived. After then, the uncertainty between the real system and the model is pointed out and several typical model uncertainty configurations are introduced. Finally, the influence of external wind acting on antenna servo system is analyzed.2.Theoretical analysis and experiment of typical control algorithms: Firstly, the performance indexes of the control system synthesis are studied. Secondly, the integral order PID control、 mixed sensitivity H∞、 linear quadratic optimal regulation control (LQR)、 linear quadratic Gaussian control (LQG)、 H2 、 H∞ control based on the system 2/∞-norm, disturbance observer based control (DOBC)、active disturbance rejection control(ADRC), are analyzed emphatically. Finally, combined with the model uncertainty of the controlled plant, experiments based on the PID, LQG, mixed sensitivity H∞ and LADRC respectively are designed for the plant with uncertain parameters. based on Monte Carlo method, the performance index changes of the uncertain system under the action of different algorithms are investigated. In addition, the control performance of nonlinear ADRC is analyzed.3.Compound control algorithm design and experiment: Based on the theoretical and experimental analysis of typical control algorithms, a mixed sensitivity H∞-GESO composite control algorithm based on loop-shaping and disturbance/uncertainty estimation and attenuation (DUEA) is proposed, in which the GESO is used to observe and eliminate the output errors caused by system uncertainties and external disturbances, and H∞ is used to realize the desired dynamic performance of the system. Then experiments are designed to verify the performance of the proposed method in signal tracking and disturbance rejection. The last part of this dissertation sums up the work. The advantages and disadvantages of the mixed sensitivity H∞-GESO control algorithm proposed are pointed out, and the further work is discussed. |
| Pages | 116 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xao.ac.cn/handle/45760611-7/4736 |
| Collection | 研究生学位论文 |
| Affiliation | 中国科学院新疆天文台 |
| First Author Affilication | Xinjiang Astronomical Observatory, Chinese Academy of Sciences |
| Recommended Citation GB/T 7714 | 李宁. 基于大口径射电望远镜指向需求的天线伺服控制算法的研究[D]. 北京. 中国科学院大学,2021. |
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| 基于大口径射电望远镜指向需求的天线伺服控（8678KB） | 学位论文 | 暂不开放 | CC BY-NC-SA | Application Full Text | ||
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