This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz force.In contrast to existing numerical optimization methods,a novel an...This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz force.In contrast to existing numerical optimization methods,a novel analytical feedback control law is developed to stabilize the in-plane and out-of-plane motions of a tether by modulating the electric current only.The saturation constraint on the current is accounted for by adding an auxiliary dynamic system to the EDTS.To enhance the robustness of the proposed controller,multiple perturbations of the orbital dynamics,modeling uncertainties,and external disturbances are approximated using a neural network in which the weighting matrix and approximation error are estimated simultaneously,such that these perturbations are well compensated for during the control design of the EDTS.Furthermore,a dynamically scaled generalized inverse is utilized to address the singular matrix in the control law.The closed-loop system is proven to be ultimately bounded based on Lyapunov stability theory.Finally,numerical simulations are performed to demonstrate the effectiveness of the proposed analytical control law.展开更多
新能源随机性使得电力系统潮流复杂多变,加之大量新能源需要远距离输送消纳,输电阻塞问题日益严重。动态热定值(dynamic line rating,DTR)技术能够提升既有架空线路的输电能力,充分发挥系统的灵活调节能力。特别是在N-1事故场景下,采用...新能源随机性使得电力系统潮流复杂多变,加之大量新能源需要远距离输送消纳,输电阻塞问题日益严重。动态热定值(dynamic line rating,DTR)技术能够提升既有架空线路的输电能力,充分发挥系统的灵活调节能力。特别是在N-1事故场景下,采用DTR技术提升线路输送能力,能够缓解严重输电阻塞。然而,传统方法在考虑N-1事故时存在维数灾难问题,因此应用DTR技术仍然存在挑战性。为此,提出了一种两阶段分布鲁棒优化(distributionally robust optimization,DRO)方法以提升架空线路的输电能力。首先,构建了架空线路暂态温度计算模型并做适当简化处理,从而保证后续优化模型的凸性。随后,建立了考虑DTR和N-1安全准则的两阶段DRO模型以避免N-1事故下的持续停电,考虑无功与网损的线性化交流潮流模型能够更准确地计算线路潮流。最后,使用IEEE-24节点系统和IEEE-118节点系统验证了所提方法的有效性。展开更多
基金supported by the National Natural Science Foundation of China under Grant Nos.11902145 and 12232011China Postdoctoral Science Foundation under Grant No.2021M691574Fundamental Research Funds for the Central Universities under Grant No.NS2022002.
文摘This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz force.In contrast to existing numerical optimization methods,a novel analytical feedback control law is developed to stabilize the in-plane and out-of-plane motions of a tether by modulating the electric current only.The saturation constraint on the current is accounted for by adding an auxiliary dynamic system to the EDTS.To enhance the robustness of the proposed controller,multiple perturbations of the orbital dynamics,modeling uncertainties,and external disturbances are approximated using a neural network in which the weighting matrix and approximation error are estimated simultaneously,such that these perturbations are well compensated for during the control design of the EDTS.Furthermore,a dynamically scaled generalized inverse is utilized to address the singular matrix in the control law.The closed-loop system is proven to be ultimately bounded based on Lyapunov stability theory.Finally,numerical simulations are performed to demonstrate the effectiveness of the proposed analytical control law.
文摘新能源随机性使得电力系统潮流复杂多变,加之大量新能源需要远距离输送消纳,输电阻塞问题日益严重。动态热定值(dynamic line rating,DTR)技术能够提升既有架空线路的输电能力,充分发挥系统的灵活调节能力。特别是在N-1事故场景下,采用DTR技术提升线路输送能力,能够缓解严重输电阻塞。然而,传统方法在考虑N-1事故时存在维数灾难问题,因此应用DTR技术仍然存在挑战性。为此,提出了一种两阶段分布鲁棒优化(distributionally robust optimization,DRO)方法以提升架空线路的输电能力。首先,构建了架空线路暂态温度计算模型并做适当简化处理,从而保证后续优化模型的凸性。随后,建立了考虑DTR和N-1安全准则的两阶段DRO模型以避免N-1事故下的持续停电,考虑无功与网损的线性化交流潮流模型能够更准确地计算线路潮流。最后,使用IEEE-24节点系统和IEEE-118节点系统验证了所提方法的有效性。
