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SSRN 2023年

作者： Wu, Chongtian Yuan, Xiaolu Kong, Benben Zou, Yitao Shi, Hong College of Energy & Power Engineering Jiangsu University of Science and Technology 2 Mengxi Jingkou Zhenjiang212003 China Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics & Astronautics 29 Yudao Street Nanjing210016 China

Lithium-ion batteries have garnered significant attention in the field of new energy technologies owing to their remarkable high energy density characteristics. This paper proposes a compact battery liquid-cooling system and perform structural optimization based on a stepwise optimization concept, aimed at comprehensively enhancing the performance of the Battery Liquid Cooling System (BLCS). Firstly, this paper conducts an energy consumption optimization of the flow velocity (V), diameter (D), and the contact angle (θ). Subsequently, the entropy weighted-TOPSIS method is utilized for objective optimization, thereby obtaining the optimal configuration based on comprehensive considerations of power consume (Pc), maximum temperature (Tmax) and maximum temperature difference (ΔT), with V=0.4 m/s, D=3 mm, θ=75°. When the initial temperature=25 ℃ and discharge rate=3 C, this structure yields the following results: Tmax =28.089 ℃, ΔT=2.884 ℃, and Pc=19.484 J. Furthermore, in the re-optimization phase, a lightweight design is applied to the system. In this phase, we optimize three parameters for the layered conductive fin: the number of layers (L), the height of each layer (Lh), and the thickness (Lw). By enumerating Lw=0, thirteen operating conditions are considered with L ranging from 1 to 4 layers, and Lh taking values of 5 mm, 7 mm, 9 mm, and 11 mm. Employing the entropy weight-TOPSIS method, the optimal solution is determined by comprehensively considering δ, Tmax, and ΔT. Under this condition, the weights for δ, Tmax, and ΔT are 41.02%, 30.82%, and 28.16%, respectively. Following comprehensive evaluation, the optimal solution is attained: L=3, Lh=7. Under these conditions, the BLCS achieves Tmax=29.196 ℃, ΔT=3.753 ℃, and δ=0.755, resulting in a weight reduction of 61 g (20.7%) for components of BLCS excluding the battery. This research through a stepwise optimization method, has accomplished a comprehensive enhancement of both energy consumption and mass for the BLCS,

关键词： Structural optimization

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Magnetic Field and Radial Force Analysis of Six-Phase Rotary Machine

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Guidance,Navigation and control 2022年第3期2卷 48-62页

作者： Ziwei Dong Liang Yan Chris Gerada School of Automation Science and Electrical Engineering Beihang University Science and Technology on Aircraft Control Laboratory Beihang University Ningbo Institute of Technology Beihang University Department of Electrical and Electronic Engineering University of Nottingham

Six-phase permanent magnet synchronous machine and the control system are also widely used in industry, precision instruments and aerospace. However, most PMSMs employ magnet patterns either in alternatively radial magnetization or Halbach array, which may constrain the performance improvement in a certain degree. Therefore, a novel six-phase trapezoidal Halbach magnet array(THMA) is proposed in this paper. Six-phase permanent magnet synchronous machines(PMSMs) can reduce the harmonic components of magnetic flux in air gap, and decrease the iron loss and electromagnetic vibration caused by harmonic torque. Thus, it helps to improve the working efficiency and depress the torque ripple of the electrical machine. Dual three-phase windings are employed for the stator design to further improve the power density and reliability of the machine. Six-phase vector model of the machine is built based on dual dq control. It can minimize the electric coupling, magnetic coupling and thermal coupling. The radial electromagnetic force of the machine under load or no load is extracted, then the harmonic decomposition of the radial electromagnetic force for the spatial with time Fourier decomposition is carried out to obtain the force amplitude of different orders which is conducive to analyze the vibration characteristics of the machine.

关键词： Six-phase permanent magnet synchronous machine radial electromagnetic force Fourier analysis

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Numerical Investigations of Phase Change Material (Pcm)-Based Battery Thermal Management System (Btms) Under Variable Gravity Environment

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SSRN 2023年

作者： Wu, Chongtian Qiu, Chenghui Yuan, Xiaolu Yuan, Nenglin Zhang, Bixiao Li, Yonghao Qin, Liwei Shi, Hong College of Energy & Power Engineering Jiangsu University of Science and Technology 2 Mengxi Jingkou Zhenjiang212003 China Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics & Astronautics 29 Yudao Street Nanjing210016 China

PCMs are widely employed in electronic thermal control systems for spacecraft because of their substantial energy storage competencies. Therefore, the influence of gravitational acceleration (GA) on PCM thermal performance is of particular importance. This study employs numerical simulation to assess PCM heat transfer efficiency and thermal behavior of BTMS cooled under varying gravitational environments (0.05 g, 0.1 g, 1 g, 10 g, and 20 g) and different inclination angles (θ=90°, 45°, 0°) via the enthalpy-porosity method. Research results indicate that as gravity increases from 0.05 g to 20 g, the melting time of PCM shortened by 15%, reducing from 95.05 s to 81.30 s. This phenomenon can be explained by the enhanced convective heat transfer capability, increasing the maximum velocity (Vmax) of the liquid PCM (PCMl) by over 12 times. Particularly, when GA= 10 g, increasing θ from 45° to 90° reduces PCM melting time by 59.05s (9.66% reduction) compared to θ=45°, while at θ=0°, it decreases by 65.75 s (10.75% reduction). Notably, at θ=45°, some unmelted solid PCM accumulates in the lower right corner of the enclosure hindering the BTMS heat transfer. Based on the characteristics of PCM melting and accumulation effects, three optimization structures for different θ are proposed in this study. It can be observed at t=240s that the enhancement of PCM melting phenomenon is particularly prominent with the presence of fins. Furthermore, by comparing CHTC curves before and after optimization, it is evident that the accumulated effect has been effectively eliminated after optimization. These research findings offer reference and insights for the design of BTMS in the aerospace field. © 2023, The Authors. All rights reserved.

关键词： Phase change materials

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Mixed Fault-Tolerant Sampled-Data Fuzzy control for Nonlinear Parabolic PDE Systems Under Deception Attacks

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International Journal of Fuzzy Systems 2022年第8期24卷 3513-3531页

作者： Li, Qian-Qian Wang, Zi-Peng Wu, Huai-Ning Li, Yueyang Li, Han-Xiong School of Electrical Engineering University of Jinan Jinan China Faculty of Information Technology Beijing University of Technology Beijing China Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing China Department of Systems Engineering and Engineering Management City University of Hong Kong Kowloon Tong Hong Kong

This paper addresses mixed $$H_2/H_\infty$$ fault-tolerant sampled-data (SD) fuzzy control for nonlinear space-varying parabolic partial differential equation (PDE) system under deception attacks. Firstly, a T–S fuzzy PDE model is given to exactly describe the nonlinear space-varying parabolic PDE system. Secondly, a fault-tolerant SD fuzzy controller via the spatial linear matrix inequalities (SLMIs) is developed based on a Lyapunov functional which is continuous at sampling times but not necessary to be positive definite in sampling intervals such that the closed-loop PDE system is exponentially stable with a mixed $$H_2/H_\infty$$ performance. Then, to solve the SLMIs, the fault-tolerant SD fuzzy control problem for space-varying parabolic PDE system is formulated as linear matrix inequality feasibility problem. Furthermore, the design condition of the suboptimal mixed $$H_2/H_\infty$$ fault-tolerant SD controller subject to deception attacks can be derived by considering the property of membership functions. Lastly, two examples are given to illustrate the design method.

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Optimal Scaled Average Consensus control of Discrete-Time Multi-Agent Systems Based on Adaptive Dynamic Programming

Optimal Scaled Average Consensus Control of Discrete-Time Mu...

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Chinese control Conference (CCC)

作者： Peiyu Zhai Mengji Shi Weihao Li Jiangfeng Yue Kaiyu Qin Jinwei Bai Ruhao Hua School of Aeronautics and Astronautics University of Electronic Science and Technology of China Chengdu China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Chengdu China China Aerodynamics Research and Development Center Computational Aerodynamics Institute Mianyang China

This paper investigates the data-driven scaled average consensus control problem of discrete-time (DT) multi-agent systems. An optimal distributed control scheme is designed to solve this problem and enable model-free online training based on adaptive dynamic programming (ADP). Firstly, the optimal scaled average consensus problem is defined via Bellman optimality principle. Then, the ADP algorithm is designed to calculate a proper approximate solution for the discrete-time Hamilton-Jacobi-Bellman (DT-HJB) equation based on generalized policy iteration. In addition, critic-actor neural networks are well constructed to fit the iterative control law and performance indices to realize the model-free online training for the data-driven control. Finally, some simulation results are given to verify the validity of the proposed optimal distributed control scheme.

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Bipartite Containment control of Nonuniform Delayed Fractional-Order Multi-Agent Systems Over Signed Networks

Bipartite Containment Control of Nonuniform Delayed Fraction...

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IEEE Conference on Decision and control

作者： Weihao Li Kaiyu Qin Jinliang Shao Lei Shi Mengji Shi Wei Xing Zheng School of Aeronautics and Astronautics University of Electronic Science and Technology of China Chengdu China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Chengdu China School of Automation Engineering University of Electronic Science and Technology of China Chengdu China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China School of Artificial Intelligence Henan University Zhengzhou China School of Computer Data and Mathematica Sciences Western Sydney University Sydney NSW Australia

In this study, the bipartite containment control problem of fractional-order multi-agent systems with nonuni-form time delays is addressed. An in-depth analysis of the system stability and bipartite containment control performance from a delay margin perspective is provided. Theoretically, the corresponding delay margin (maximum allowable time delay) over undirected and directed signed networks is obtained in the presence of nonuniform time delays, respectively. In addition, numerical relationships between the delay margin and the control coefficients, fractional order, and topology parameters are established, thus enabling easy and direct calculation of the maximum allowable time delay and facilitating distributed controller design and controller parameter tuning. Finally, some simulation examples are given to verify the effectiveness of the proposed bipartite containment controller and the obtained delay margin.

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Innovative Liquid Cooling Channel Enhanced Battery Thermal Management (Btm) Structure Based on Stepwise Optimization Method

SSRN

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SSRN 2023年

关键词： Structural optimization

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Fault-tolerant Model Predictive control for Hypersonic Vehicle Based on Sum of Squares

Fault-tolerant Model Predictive Control for Hypersonic Vehic...

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第40届中国控制会议

作者： Xiaohe Yang Weijie Lv Chaofang Hu Yongtai Hu School of Electrical and Information Engineering Tianjin University Aviation Key Laboratory of Science and Technology on Aircraft Control Facri

In this paper, a robust model predictive controller based on sum of squares（SOS-RMPC） is proposed to realize the trajectory tracking control of hypersonic vehicle with actuator fault. Firstly, the polytopic feedback linearization error model of hypersonic vehicle with actuator fault is derived. The integration of altitude and velocity are introduced to eliminate the steady state error. The lose efficiency fault of actuator is separated from control input and the additional bounded disturbance term is formed. Secondly, the real input constraint is converted to virtual state-dependent input constraint in polynomial. Finally,a composite control law with and without virtual state-dependent constraint is proposed, and the SOS-RMPC fault-tolerant controller is designed. By SOS technology, the virtual state-dependent input constraint in polynomial is transformed into convex optimization problem of linear matrix inequality（LMI）. The norm-bounded theory is applied to suppress the disturbance. The simulations show that the designed controller can realize trajectory tracking control of hypersonic vehicle with actuator fault.

关键词： Hypersonic vehicle Fault-tolerant control Feedback linearization Robust model predictive control Sum of Squares

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Explicit and Implicit Models in Infrared and Visible Image Fusion

arXiv

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arXiv 2022年

作者： Wang, Zixuan Sun, Bin School of Aeronautics and Astronautics University of Electronic Science and Technology of China Chengdu611731 China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Chengdu611731 China

Infrared and visible images, as multi-modal image pairs, show significant differences in the expression of the same scene. The image fusion task is faced with two problems: one is to maintain the unique features between different modalities, and the other is to maintain features at various levels like local and global features. This paper discusses the limitations of deep learning models in image fusion and the corresponding optimization strategies. Based on artificially designed structures and constraints, we divide models into explicit models, and implicit models that adaptively learn high-level features or can establish global pixel associations. Ten models for comparison experiments on 21 test sets were screened. The qualitative and quantitative results show that the implicit models have more comprehensive ability to learn image features. At the same time, the stability of them needs to be improved. Aiming at the advantages and limitations to be solved by existing algorithms, we discuss the main problems of multi-modal image fusion and future research directions. Copyright © 2022, The Authors. All rights reserved.

关键词： Image fusion

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Lvt-Pso: An Enhanced Task Assignment Algorithm of Dynamic Targets Attacks for Multi-Uav Systems with Complex Constraints

SSRN

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SSRN 2022年

作者： Kang, Ruimeng Li, Hui Li, Mingfu Qian, Xiaomei Li, Wanting School of Aeronautics and Astronautics University of Electronic Science and Technology of China Chengdu611731 China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Chengdu611731 China

Collaborative task assignment is the fundamental research of multi-UAV coordinated control problem. The key factors affecting the task assignment are analyzed and a comprehensive evaluation system is established considering the range, time window, attack reward and threat. In light of it, an optimal particle swarm (PSO) task assignment algorithm is proposed based on local random search (LRS), variable neighborhood search (VNS), and tabu list-variable neighborhood descent (TL-VND), and a particle swarm codec algorithm is designed to solve the "deadlock" problem caused by simultaneous attacks. In case of threats, an obstacle avoidance method is designed via the combination of the bisection method and PSO. Meanwhile, the adaptive learning factors are introduced during the process of particles updating. To improve the global search capability of the algorithm, the LRS algorithm is embedded in the framework of VNS-PSO, and a task sequence generated by TL-VND algorithm is seen as a particle in the swarm to improve the convergence speed of the algorithm. Finally, simulation experiments are conducted to demonstrate the effectiveness of optimized PSO. Compared with VNSPSO, the proposed algorithm can solve the attack task assignment problem of moving targets in a faster convergence speed. © 2022, The Authors. All rights reserved.

关键词： Particle swarm optimization (PSO)

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