Dynamics and Control of Electrodynamic Tether Systems

电动系绳系统的动力学和控制

• 批准号: 341917-2013
• 负责人: Zhu, ZhengHong
• 金额: $ 2.33万
• 依托单位: York University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=638818
• 关键词: Dynamics; Control; Electrodynamic; Tether; Systems

Electrodynamic tethers (EDTs) are an innovative approach to generate propulsion for boost and deorbit maneuver and electricity onboard spacecraft without consuming propellant. Over the past five decades, 12 out of 26 orbital and suborbital tether missions flew with EDTs. However, the system is prone to the long-term instability caused by the time-varying excitation of Lorentz force. Thus, a thorough understanding of the long-term dynamic stability of an EDT system is essential for its useful application in space. In spite of great achievements in the EDT theory and electrodynamic tethered systems, a number of interesting challenges still exists in the fundamentals of coupled EDT dynamics and long-term dynamic stability. Therefore, the objectives of this discovery program are to systematically study the coupled electro-mechanical dynamics and optimal control of the long-term stability of EDT systems. In this new approach, we will formulate a multiphysics model of dynamics of a bare and flexible EDT coupled with electricity generation by orbit motion limited theory. Based on the new multiphysics model, the parameters of EDT systems will be optimized by applying multiobjective optimization procedure for (a) fastest time in boost or deorbit maneuver or (b) maximum energy generation for given payloads onboard spacecraft, while minimizing the EDT length and end masses. The long-term dynamic stability of an EDT system will be achieved by finding an optimal balance between a stable oscillation of a time-varying EDT system and given mission objectives using the nonlinear-programming optimization procedure and the robust finite receding horizon control theory. Finally, ground testing will be conducted to validate the dynamics and control strategy. The outcome of the proposed research program will be (i) a high-fidelity multiphysics EDT model essential for EDT systems, (ii) a robust optimal control algorithm, and (iii) training of 14 HQP in an interdisciplinary and collaborative environment. It will advance our knowledge in new propulsion or power generation for future space exploration and enhance the competitiveness of Canadian space industry.

电动力系绳（EDTs）是一种不消耗推进剂而产生推进力和离轨机动以及航天器上电力的创新方法。在过去的50年里，26次轨道和亚轨道系绳任务中有12次使用了edt。但由于洛伦兹力的时变激励，系统容易出现长期不稳定。因此，全面了解EDT系统的长期动态稳定性对于其在空间中的有效应用至关重要。尽管在EDT理论和电动力系索系统方面取得了巨大的成就，但在耦合EDT动力学和长期动态稳定性的基础方面仍然存在许多有趣的挑战。因此，这个发现计划的目标是系统地研究耦合机电动力学和EDT系统长期稳定性的最优控制。在这种新方法中，我们将根据轨道运动限制理论建立一个与发电耦合的裸柔性EDT动力学的多物理场模型。基于新的多物理场模型，EDT系统的参数将通过应用多目标优化程序进行优化(a)加速或脱轨机动的最快时间或(b)给定航天器有效载荷的最大能量产生，同时最小化EDT长度和末端质量。利用非线性规划优化程序和鲁棒有限渐退地平线控制理论，在给定任务目标和时变EDT系统的稳定振荡之间寻找最优平衡点，从而实现EDT系统的长期动态稳定性。最后，将进行地面测试以验证动力学和控制策略。拟议研究计划的结果将是(i) EDT系统必不可少的高保真多物理场EDT模型，（ii）鲁棒最优控制算法，以及（iii）在跨学科和协作环境中训练14 HQP。它将提高我们在未来太空探索的新推进或发电方面的知识，并提高加拿大航天工业的竞争力。