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Electrochromic Orbit control for Smart-Dust Devices

JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第5期35卷 1548-1558页

作者： Luecking, Charlotte Colombo, Camilla McInnes, Colin R. Univ Strathclyde Adv Space Concepts Lab Glasgow G1 1XJ Lanark Scotland

Recent advances in microelectromechanical systems technology are leading to spacecraft that are the shape and size of computer chips, so-called SpaceChips or smart-dust devices. These devices can offer highly distributed sensing when used in future swarm applications. However, they currently lack a feasible strategy for active orbit control. This paper proposes an orbit-control methodology for future SpaceChip devices, which is based on exploiting the effects of solar radiation pressure using electrochromic coatings. The concept presented makes use of the high area-to-mass ratio of these devices and, consequently, the large force exerted upon them by solar radiation pressure to control their orbit evolution by altering their surface optical properties. The orbital evolution of SpaceChips due to solar radiation pressure can be represented by a Hamiltonian system, allowing an analytic development of the control methodology. The motion in the orbital element phase space resembles that of a linear oscillator, which is used to formulate a switching control law. Additional perturbations and the effect of eclipses are accounted for by modifying the linearized equations of the secular change in orbital elements around an equilibrium point in the phase space of the problem. Finally, the effectiveness of the method is demonstrated in a test case scenario.

关键词： Optical Properties Eclipses control algorithm Orbital Eccentricity Earth Solar Radiation Orbital Elements Right Ascension Solar Sail Time Optimal control

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Study on the control Strategy and algorithm of Cooling Source Based on Cooling on Demand in Intelligent Building Management

Study on the Control Strategy and Algorithm of Cooling Sourc...

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2nd International Conference on Information Management, Innovation Management and Industrial Engineering

作者： Tian Peizhe Zhang Enxiang Li Chunwang Sun Yuying Beijing Union Univ Biochem Engn Coll Beijing Peoples R China Beijing Univ Technol Architectural Engn Coll Beijing Peoples R China

ISBN: (纸本)9780769538761

From the idea of unified energy management, this paper analyzed the composition and the energy saving ways of the cooling source in intelligent building, established the applicable chiller plant control algorithmic modules on the basis of the innovative control strategy of cooling on demand and the control module library. Study focused on the optimized control algorithms of the chilled water supply temperature set-point control according to the cooling request on demand, the chiller operating numbers and proper operating order and running cycle control, and the chilled water pump frequency conversion control according to the cooling request on demand. The feasibility and stability was tested and verified in the laboratory. The ideal effects were also achieved in a practical project in Ningxia Hui autonomous region, China. The results show that the system can be loaded/unloaded efficiently, and the fluctuation of water temperature at the chiller's outlet around the setpoint remains quite small, which reflect very good control precision and notable energy-saving effects.

关键词： control strategy control algorithm cooling on demand cooling source building management

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Smooth motion control of the adaptive cruise control system by a virtual lead vehicle

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INTERNATIONAL JOURNAL OF AUTOMOTIVE TECHNOLOGY 2012年第1期13卷 77-85页

作者： Kim, S. G. Tomizuka, M. Cheng, K. H. Univ Calif Berkeley Dept Mech Engn Berkeley CA 94720 USA Ind Technol Res Inst Hsinchu 31040 Taiwan

The adaptive cruise control system maintains the appropriate distance to the lead vehicle when the lead vehicle exists and maintains the desired speed when no lead vehicle is detected. A virtual lead vehicle scheme is introduced to make the switching between the speed control algorithm and the distance control algorithm unnecessary and simplify the structure of the control system. The speed and the position of the virtual vehicle can be decided by the control system according to the current situation. Smoother responses are achieved by the virtual lead vehicle scheme compared to the conventional mode switching scheme. This method is also shown to provide a good reaction for when a lead vehicle cuts in or out. A linear quadratic controller with variable weights is suggested to control the virtual lead vehicle. This scheme shows improved performance in terms of passenger comfort and fuel efficiency of the host vehicle.

关键词： Automotive control Cruise control Vehicle dynamics Switching algorithms control algorithm

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Centralized and Distributed Active and Reactive Power control of a Utility Connected Microgrid Using IEC61850

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IEEE SYSTEMS JOURNAL 2012年第1期6卷 58-67页

作者： Colet-Subirachs, Alba Ruiz-Alvarez, Albert Gomis-Bellmunt, Oriol Alvarez-Cuevas-Figuerola, Felipe Sudria-Andreu, Antoni Catalonia Inst Energy Res Barcelona 08019 Spain Endesa Network Factory Barcelona 08004 Spain Tech Univ Catalonia Dept Elect Engn Barcelona 08034 Spain

This paper describes the control algorithm of a utility connected microgrid, based on independent control of active and reactive power and operating in centralized and distributed operation mode. The microgrid is composed of several (three in the experimental tests conducted) configurable units, including generation, storage, and load units. These units are interfaced with the microgrid through a voltage source converter and are controlled by the nodes of the communication system by means of IEC 61850. The proposed control strategy is validated by simulation in MATLAB/Simulink and with experimental tests.

关键词： control algorithm IEC 61850 microgrid

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A COMPARATIVE STUDY ON THE POWER CHARACTERISTICS AND control STRATEGIES FOR PLUG-IN HYBRID ELECTRIC VEHICLES

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INTERNATIONAL JOURNAL OF AUTOMOTIVE TECHNOLOGY 2012年第3期13卷 505-516页

作者： Ma, C. Kang, J. Choi, W. Song, M. Ji, J. Kim, H. Sungkyunkwan Univ Sch Mech Engn Gyeonggi 440746 South Korea

A comparative study was performed on two types of plug-in hybrid electric vehicles (PHEVs): the GM Volt and the Toyota Prius Plug-in Hybrid. First, the powertrain models of the two vehicles were derived. Based on the dynamic models, a detailed component control algorithm was developed for each PHEV Specifically, a control algorithm was proposed for motor generator I (MG1) and MG2 to achieve optimal engine operation. Additionally, an energy management strategy for selecting the operation mode was developed from the viewpoint of fuel economy, battery state of charge and vehicle velocity. Using the dynamic model of the control algorithm for each PHEV, simulations were performed, and the simulation results were verified by comparing them with those obtained using the Powertrain System Analysis Toolkit simulator for the plug-in Prius. Based on the simulation results, a comparative study was performed, and it was found that the role and capacity of MG1 and MG2 and the mode selection algorithm must be determined depending on the configuration of the PHEV.

关键词： PHEV Powertrain control algorithm Energy management strategy Comparative study

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Model of Dynamics and control of Tracking-Searching Head, Placed on a Moving Object

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JOURNAL OF AUTOMATION AND INFORMATION SCIENCES 2012年第5期44卷 38-47页

作者： Krzysztofik, I. Koruba, Z. Kielce Univ Technol Poland Kielce Poland

We stated mathematical model of dynamics and control algorithm of tracking-searching head, placed on a ground moving object. Numerical analysis was performed for investigation of head dynamics under effect of kinemati... 详细信息

关键词： mathematical model dynamics control algorithm tracking- searching head moving object numerical analysis kinematic excitations

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Estimation of the state-of-charge of gel lead-acid batteries and application to the control of a stand-alone wind-solar test-bed with hydrogen support

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2012年第15期37卷 11090-11103页

作者： Gonzalez, I. Ramiro, A. Calderon, M. Calderon, A. J. Gonzalez, J. F. Univ Extremadura EII Dept Appl Phys E-06071 Badajoz Spain Univ Extremadura EII Dept Elect Engn E-06071 Badajoz Spain

In hybrid renewable energy systems, batteries act as a DC bus to provide constant voltage and to smooth out commutations between the generating devices. These batteries are usually of a lead-acid type and operate under harsh variable conditions due to fluctuations of both solar radiation and wind speed. Precise knowledge of the state-of-charge of the batteries, and hence of their available energy, play a key role in effecting efficient control and energy management of the installation. The present study had a twofold aim. One objective was to adjust and validate a method based on coulomb counting to estimate the state-of-charge (SOC) of a gelled lead-acid battery which is the DC bus of a hybrid wind-solar system with hydrogen storage. Other works evaluate SOC models based on several parameters, however, the present proposal based on experimental measurements involves only a few parameters. The second objective was to modify the installation's control algorithm to use the battery's calculated SOC as control parameter instead of its voltage. The results of a test-bed system, showing how the system evolved under real operating conditions, constitute a proof-of-concept of the validity of the method. Copyright (c) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Hybrid solar-wind hydrogen system Valve-regulated lead-acid battery Gel electrolyte State-of-charge control algorithm Power management strategy

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Design and control of a three degree-of-freedom permanent magnet spherical actuator

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SENSORS AND ACTUATORS A-PHYSICAL 2012年 180卷 75-86页

作者： Chen, Weihai Zhang, Liang Yan, Liang Liu, Jingmeng Beihang Univ Sch Automat Sci & Elect Engn Beijing 100191 Peoples R China

This paper presents a permanent magnet (PM) spherical actuator embedded with a novel three-dimensional (3D) orientation measurement system. The study covers actuator design, torque modeling, and motion control. The spherical actuator consists of a stator with 24 coils and a rotor with 8 PM poles. A high accuracy and resolution, non-blinding 3D measurement mechanism is designed for the rotor orientation detection. The torque output is formulated from finite element (FE) computation and curve fitting method. Due to the nonlinear property of dynamic model, computed torque control law is utilized for the three degree-of-freedom (3-DOF) system motion control. The space geometry method is employed to study the redundancy feature of current inputs, which offers the opportunity for control optimization to improve the power efficiency and the fault tolerance capability of the spherical actuator. Simulations and experiments are then conducted on the developed prototype to validate the design concept, mathematic models and control strategy. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Spherical actuator Orientation measurement Torque modeling control algorithm

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Robust Attitude Coordination control for Spacecraft Formation Flying Under Actuator Failures

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JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第4期35卷 1247-1255页

作者： Zou, An-Min Kumar, Krishna Dev Ryerson Univ Dept Aerosp Engn Toronto ON M5B 2K3 Canada

This paper examines attitude coordination control for spacecraft formation flying. A class of distributed adaptive fault-tolerant attitude coordination control laws is proposed. The proposed control laws do not require online identification of failures. Using the Lyapunov approach and graph theory, it is shown that the control laws guarantee a group of spacecraft that simultaneously track a common time-varying reference attitude, even when the reference attitude is available only to a subset of the members of a group. Finally, numerical simulation is presented to show that the distributed controller is successful in achieving high-attitude tracking and synchronization performance, even in the presence of an unknown mass moment of inertia matrix, bounded external disturbances, actuator failures, and control saturation limits.

关键词： Spacecraft Formation Flying Actuators Attitude Tracking Numerical Simulation Attitude Stabilization Spacecraft Attitude Terminal Sliding Mode control algorithm Adaptive control Systems Onboard Computing

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Regulation and force control using sliding modes to reduce rebounds in a mechanical system subject to a unilateral constraint

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IET control THEORY AND APPLICATIONS 2012年第18期6卷 2785-2792页

作者： Rascon, R. Alvarez, J. Aguilar, L. T. CICESE Res Ctr Elect & Telecommun Dept San Diego CA 92143 USA Inst Politecn Nacl Tijuana 22510 Mexico

In this study, a control algorithm is proposed, based on the sliding-mode technique, to regulate a single degree of freedom mechanical system subject to a unilateral constraint. The system may be in non-constrained motion at some time or in constrained motion at some other time. The system motion can be divided in three phases: free motion, constrained motion and transition (from non-constrained to constrained motion and vice versa). Only one control law is designed for the system, regardless of the motion phase. It is shown that the non-linear system is globally asymptotically stable and achieves zero steady-state position error. Numerical and experimental results show the performance of the proposed controller.

关键词： sliding-mode technique Multivariable control systems force control control law design variable structure systems Stability in control theory control system synthesis control system analysis and synthesis methods Nonlinear control systems unilateral constraint free motion phase nonconstrained motion system Mechanical variables control global asymptotic stability constrained motion phase nonlinear control systems nonlinear system transition phase steady-state position error 1-DOF mechanical system control algorithm single-degree-of-freedom mechanical system rebound reduction asymptotic stability

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