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Nonreciprocity of energy transfer in a nonlinear asymmetric oscillator system with various vibration states

Applied Mathematics and Mechanics(English Edition) 2023年第5期44卷 727-744页

作者： Jian’en CHEN Jianling LI Minghui YAO Jun LIU Jianhua ZHANG Min SUN Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin 300384China School of Aeronautics and Astronautics Tiangong UniversityTianjin 300387China Agricultural Information Institute of Chinese Academy of Agricultural Sciences Key Laboratory of Agricultural Big DataMinistry of Agriculture and Rural AffairsBeijing 100081China School of Science Tianjin Chengjian UniversityTianjin 300384China

The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear *** slow-flow equation of the system is derived by the complexification-averaging *** semi-analytical solutions to this equation are obtained by the least squares method,which are compared with the numerical solutions obtained by the Runge-Kutta *** distribution of the average energy in the system is studied under periodic and chaotic vibration states,and the energy transfer along two opposite directions is *** effect of the excitation amplitude on the nonreciprocity of the system producing the periodic responses is analyzed,where a three-stage energy transfer phenomenon is *** the first stage,the energy transfer along the two opposite directions is approximately equal,whereas in the second stage,the asymmetric energy transfer is *** energy transfer is also asymmetric in the third stage,but the direction is reversed compared with the second ***,the excitation amplitude for exciting the bifurcation also shows an asymmetric *** vibrations are generated around the resonant frequency,irrespective of which linear oscillator is *** excitation threshold of these chaotic vibrations is dependent on the linear oscillator that is being *** addition,the difference between the energy transfer in the two opposite directions is used to further analyze the nonreciprocity in the *** results show that the nonreciprocity significantly depends on the excitation frequency and the excitation amplitude.

关键词： nonreciprocity strong nonlinearity energy transfer chaotic vibration higher branch of response

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Robust Delay-Dependent Stability for Uncertain Linear systems with Time-Varying Delay 49

Robust Delay-Dependent Stability for Uncertain Linear System...

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49th Annual Conference of the IEEE Industrial Electronics Society, IECON 2023

作者： Chen, Dong-Shuai He, Yong Shangguan, Xing-Chen School of Automation China University of Geosciences Wuhan430074 China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education China

ISBN: (纸本)9798350331820

This paper investigates the problem of stability analysis for the uncertain linear systems with time-varying delay. Firstly, an uncertain linear system model considering time-varying delay is established. Then based on the Lyapunov-Krasovskii functional (LKF) method, a novel robust delay-dependent stability criterion is proposed, which is benefited by a new augmented LKF with more effective time-delay information and the use of a tighter integral inequality to estimate functional derivative. The stability criterion obtained is less conservative. At last, a numerical example shows the superiority and effectiveness that the method used in this paper. © 2023 IEEE.

关键词： Time delay

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Fixed-time Sliding Mode control for Buck-Boost Converter 4

Fixed-time Sliding Mode Control for Buck-Boost Converter

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2022 4th International Conference on Energy systems and Electrical Power, ICESEP 2022

作者： Zhou, Yusheng Liu, Shilin Wang, Ning Key Laboratory of Advanced Perception and Intelligent Control of High-end Equipment Ministry of Education Anhui Polytechnic University Wuhu241000 China

To obtain stable state within the fixed time and reduce the influence of uncertain device parameters on the buck-boost converter, this paper proposes the fixed-time sliding mode control (FSMC) and fixed-time adaptive sliding mode control (FASMC). Firstly, we build the state-space average model on the basis of the continuous conduction mode (CCM) of the buck-boost converter. Secondly, the fixed-time sliding mode surface and FSMC are studied when the device parameters are known. By analyzing the Lyapunov stability, it has been proved that the system can reach a stable state within the fixed time, besides the maximum of the fixed time is merely determined by the parameters of the control strategy. Thirdly, when the system device parameters are unknown, the FASMC is developed ensuring the system can reach the adjacent domain of the equilibrium point within the fixed time. Finally, the effectiveness of the proposed control strategies was verified by the simulation experiments. © 2022 Institute of Physics Publishing. All rights reserved.

关键词： Buck-Boost converter

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Voltage control for Black-Start Based on Energy Storage Station and Wind Farm 4

Voltage Control for Black-Start Based on Energy Storage Stat...

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4th International Conference on intelligent Power and systems, ICIPS 2024

作者： Zhu, Yuanzhen Wei, Xinyu Li, Tianshu Chen, Yiheng Zhou, Ning Fang, Qiao Zhao, Kang Sun, Runjia State Grid Shandong Electric Power Company Electric Power Science Research Institute Shandong Smart Grid Technology Innovation Center Jinan China Key Laboratory of Power System Intelligent Dispatch and Control The Ministry of Education Jinan China

ISBN: (纸本)9798331532765

Energy storage station (ESS) and wind farm (WF) have the potential to serve as a black-start sources to accelerate the power system restoration after blackout. However, the voltage security problem when start the auxiliary machines of power plants limit their reliability as black-start sources. A voltage control method is proposed for ESS and WF combined black-start sources to improve the voltage security during black-start. Firstly, the black-start process based on grid-forming ESS and WF is presented, and the voltage control framework is established. Then, a predictive control method considering the impact of active power on voltage variations is proposed, in which different optimization modes are established to obtain the active and reactive control sequences for WF and ESS. Finally, black-start simulation with Matlab/Simulink demonstrate the proposed method can improve the voltage security level when starting auxiliary machines of power plants. © 2024 IEEE.

关键词： Predictive control systems

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Optical funnel:broadband and uniform compression of electromagnetic fields to an air neck

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Photonics Research 2021年第9期9卷 1675-1682页

作者： FEI SUN YICHAO LIU YIBIAO YANG Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceCollege of Physics and OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024China

An optical funnel,which performs as a passive electromagnetic compressor,can guide electromagnetic waves from a wide inlet to a narrow outlet without reflectance/scattering and squeeze electromagnetic fields uniformly to an air *** this study,an optical funnel is designed by precisely filling subwavelength ceramic blocks with a gradient refractive index inside a tapered *** gradient refractive index is designed by transformation optics,which is isotropic and all above unit,thus exhibiting a broadband *** to the mechanism of impedance matching over the whole funnel,extremely low reflectance/scattering and stable enhancement of fields can be *** field enhancement factor in different regions of the funnel(e.g.,in the air neck)can be flexibly designed just by modifying the funnel-width ratios.

关键词： scattering reflectance refractive

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PI-funnel and inverse hysteresis compensation cascade control of smart soft dielectric elastomer actuator

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control Theory and Technology 2024年第4期22卷 552-567页

作者： Peng Huang Yawu Wang Yue Zhang Jundong Wu Chun-Yi Su School of Automation China University of GeosciencesWuhan430074HubeiChina Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074HubeiChina Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of EducationWuhan430074HubeiChina Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQCH3G 1M8Canada

Smart soft dielectric elastomer actuators(SSDEAs)possess wide applications in soft robotics due to their properties similar to natural muscles,including large deformation ratio,high energy density,and fast response ***,the complicated asymmetric and rate-dependent hysteresis property,creep property and quadratic input property of the SSDEA pose enormous challenges to its dynamic modeling and motion *** this paper,first,we construct the dynamic model of the SSDEA by connecting a square module,a one-sided Prandtl–Ishlinskii(OSPI)model and a linear system in series to describe the above *** key and innovative aspect of the dynamic modeling lies in cascading the square module in series with the OSPI model to construct the asymmetric hysteresis ***,a PI-funnel and inverse hysteresis compensation(PIFIHC)cascade control method of the SSDEA is proposed to actualize its tracking control *** performing the inversion operation on the asymmetric hysteresis model,the inverse hysteresis compensation controller(IHCC)is designed to compensate the asymmetric hysteresis property and quadratic input property of the *** addition,a PI-funnel controller is designed to cascade with the IHCC to construct the PIFIHC cascade controller to obtain a good tracking ***,the stability analysis of the PIFIHC cascade control system of the SSDEA is performed to theoretically prove that the tracking error can be controlled within the performance funnel and the steady-state error converges to ***,several practical tracking control experiments of the SSDEA are conducted,and RRMSEs are less than 2.30%for all *** experimental results indicate the effectiveness and feasibility of the proposed PIFIHC cascade control method of the SSDEA.

关键词： Smart soft dielectric elastomer actuator Dynamic modeling Inverse hysteresis compensation controller PI-funnel controller Cascade controller

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3D bioprinting of a dermal scaffold for full-thickness skin tissue regeneration

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Bio-Design and Manufacturing 2025年第1期8卷 68-84,I0039-I0041页

作者： Lu Han Zixian Liu Meng Li Zhizhong Shen Jianming Wang Shengbo Sang Shanxi Key Laboratory of Micro Nano Sensors&Artificial Intelligence Perception College of Electronic Information and Optical EngineeringTaiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System of the Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China Shanxi Research Institute of 6D Artificial Intelligence Biomedical Science Taiyuan 030031China General Hospital of TISCO Taiyuan 030809China

Dermal substitutes have provided a template for the regeneration and reconstruction of the ***,the healed skin tissue often exhibits abnormal morphology and functionality,including scarring and *** this study,a composite bioink composed of methacrylated gelatin(GelMA)and chitosan oligosaccharide(COS)was proposed for printing a dermal scaffold using digital light processing(DLP)*** GelMA/COS bioink exhibited suitable porosity,swelling,degradation rate,and mechanical *** inclusion of COS demonstrated antibacterial effects against both Gram positive and Gram-negative bacteria,while simultaneously fostering the proliferation of human dermal fibroblasts(HDFs).Additionally,the application of COS could effectively reduce the expression levels of fibrosis-related genes,such as collagen I,collagen III,and fibronectin *** three-dimensionally printed cell-laden dermal scaffold exhibited excellent shape fidelity and high cellular viability,facilitating the extension of HDFs along the scaffold and the simultaneous secretion of extracellular matrix ***,the HDF-laden dermal scaffold transplanted into full-thickness skin defect sites in nude mice was shown to accelerate wound closure,reduce inflammation,and improve wound ***,the DLP-printed dermal scaffold provides an appealing approach for effectively treating full-thickness skin defects in clinical settings.

关键词： 3D printing Dermal scaffold Photo-cross-linking Skin tissue regeneration

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Data-Driven Early Warning for Dynamic Insecurity Risk of Hybrid AC/DC Power Grids

Data-Driven Early Warning for Dynamic Insecurity Risk of Hyb...

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2023 International Conference on Power system Technology, PowerCon 2023

作者： Yan, Jiongcheng Li, Changgang Liu, Yutian Zhu, Yuanzhen Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan China Electric Power Research Institute of State Grid Shandong Electric Power Company Jinan China

ISBN: (纸本)9798350300222

The dynamic interactions between AC and DC systems and the uncertainty of renewable generation increase the risk of cascading failures and bring challenges for the secure operation of hybrid AC/DC grids. Insecurity early warning identifies the security risk and guides the control decision-making, which is important for the secure power system operation. To achieve fast insecurity early warning, a data-driven early warning method for dynamic insecurity risk is proposed in this paper. First, Latin hypercube sampling and improved K-medoids algorithm are utilized to generate typical operating conditions (OCs) in the future. Then, stacking denoising autoencoders and ensemble extreme learning machines are deployed to construct security risk assessment models to fast assess the dynamic security of typical OCs. And model update is performed to ensure the assessment accuracy when cascading failures occur. Finally, the insecure OCs are ranked into different insecure levels based on the control cost needed to ensure the system security. Simulation results of the Northwest hybrid AC/DC grid in China demonstrate that the proposed method can achieve fast insecurity early warning and effectively track the security risk tendency during the process of cascading failures. © 2023 IEEE.

关键词： Risk assessment

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Enhancing Demodulation Performance of DCM Algorithm inφ-OTDR system Through Temporal Spline Interpolation

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Photonic Sensors 2024年第3期14卷 52-63页

作者： Tingyu WANG Jianzhong ZHANG Zhe MA Xiang HE Weizhe LI Binyuan YANG Mingjiang ZHANG Key Laboratory of Advanced Transducers and Intelligent Control Systems(Ministry of Education and Shanxi Province) Taiyuan University of TechnologyTaiyuan 030024China College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Physics Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China

For expanding the amplitude-frequency response range of the differential cross-phase multiply(DCM)algorithm in theφ-OTDR system,a temporal spline interpolation(TSI)method is proposed to pre-process Rayleigh backscattering(RBS)*** the TSI method,the discrete temporal signals characterizing RBS traces are subjected to interpolation,facilitating a reduction in differential approximation ***,in turn,establishes a heightened level of precision in phase demodulation,especially relevant across extensive sensing *** comparing the recovered time-domain waveforms and the corresponding power spectral densities without and with the TSI,the above improvement effect has been experimentally validated by utilizing the *** results show that,with the TSI,the amplitude-frequency response range of the DCM algorithm is enlarged by 2.78 times,and the new relationship among f_(pulse),f,and D under the root mean square error(RMSE)tolerance less than 0.1 can be expressed as 1.9(D+1)f≤f_(pulse).This contribution underscores a substantial advancement in the capabilities of the DCM algorithm,holding promise for refined performance in optical fiber sensing applications.

关键词： φ-OTDR DCM algorithm phase demodulation 3×3 coupler temporal spline interpolation

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Analytical Monodromy Matrix Method for Small-Signal Stability Analysis of Grid-Connected Modular Multilevel Converter systems

SSRN

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SSRN 2024年

作者： Jia, Xiaofan Ye, Hua Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University Jinan250061 China

Modular multilevel converters (MMCs) have been widely used in high-voltage direct current (HVDC) transmission systems, renewable energy and storage integration, static var compensation, and so on. The nonlinear time-periodic nature of MMCs leads to complex harmonic interactions and poses significant challenges to the small-signal stability analysis of grid-connected MMC systems. The Floquet theory-based monodromy matrix method can accurately achieve this task but requires time-consuming numerical integration to construct the matrix. To address this, an analytical monodromy matrix method is proposed in this paper for efficient and accurate small-signal stability analysis of grid-connected MMC systems. First, an analytical monodromy matrix of linear time-periodic (LTP) systems, i.e., the system's state transition matrix over a period, is efficiently constructed by applying the Chebyshev collocation method instead of numerical integration. In addition to low computational burden, the analytical feature of the matrix allows one to derive the derivative-based eigenvalue sensitivity. Then, the system free-response solution is efficiently computed by means of a set of analytical state transition matrices. By using the fast Fourier transform, the effective oscillation components in critical LTP modes and the related participation factors are identified. Both participation factor analysis and damping ratio analysis can be performed to gain insightful characterization of system dynamics. The correctness and effectiveness of the proposed method are verified on an exemplary grid-connected MMC system by both numerical and experimental results. © 2024, The Authors. All rights reserved.

关键词： Fast Fourier transforms

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