检索结果-内蒙古大学图书馆

IEEE Power and Energy Conference at Illinois (PECI)

作者： Ajala, Olaoluwapo Sauer, Peter IEEE United States

ISBN: (纸本)9781479948819

With appropriate control algorithms, grid-connected photovoltaic (PV) systems can provide real and reactive power to meet power system needs. However, the intermittency of solar irradiance and the stochastic nature of reactive power demand affect the dynamic performance of these systems. This paper presents a method for stochastic modeling and simulation of grid-connected three-phase photovoltaic systems. The state variables of concern are the real and reactive power delivered to the grid, and the line currents. The objective of this work is to model the statistics of the reactive power demand as a linear stochastic differential equation driven by a wiener process, model the solar irradiance and temperature as random variables, develop a dynamic performance stochastic model of the entire system, and ascertain the time evolution of the first and second moments of the state variables.

关键词： differential equations photovoltaic power systems power grids reactive power stochastic processes PV systems Wiener process control algorithms dynamic performance stochastic model grid-connected three-phase photovoltaic system grid-connected three-phase photovoltaic systems line currents linear stochastic differential equation random variables reactive power solar irradiance intermittency state variables stochastic modeling stochastic processes Arrays Equations IP networks Inverters Mathematical model Reactive power Stochastic processes

来源：评论

学校读者我要写书评

暂无评论

VEHICLE ROLLOVER DETECTION INDEX

引用

ASME International Mechanical Engineering Congress and Exposition

作者： Moshchuk, Nikolai Chen, Shih-Ken Gen Motors Corp Warren MI 48090 USA

ISBN: (纸本)9780791843864

Vehicle rollover resistance can be enhanced using differential braking control, rear-wheel steering, front steering control, suspension damping control, or the combination of any of them. In each control action, the controller receives the vehicle dynamics information from various sensors, such as a yaw-velocity sensor, a lateral accelerometer, a roll-velocity sensor (if available), and suspension displacement sensors (if available), and determines a control action to be taken. A balance between controlling vehicle roll motion and vehicle yaw motion needs to be reached to achieve the optimal vehicle response. Therefore, detection of the current and impending vehicle situations, especially pertaining to the vehicle roll, is vital for the quality of control. Various methodologies have been developed in the past to detect vehicle situations that may lead to rollover. Generally, rollover detection is based on roll velocity sensor and roll angle estimation. In most of these methods, thresholds for roll velocity and roll angle are established to detect imminent rollover. Even though roll velocity and roll angle are the two most important elements in vehicle roll motion, they may not be sufficient to timely detect impending rollover. This paper proposes a vehicle rollover detection index that can be used in a control algorithm to enhance vehicle rollover resistance. It uses roll angle and velocity (measured or estimated), yaw velocity, vehicle speed, and lateral acceleration. Further enhancement to the proposed algorithm is then briefly discussed that includes the effect of vehicle lateral load transfer on the detection.

关键词： Vehicle dynamics control algorithms algorithms Sensors Vehicles Braking control Displacement Accelerometers Wheels control equipment Stress Damping Yaw

来源：评论

学校读者我要写书评

暂无评论

Design and Implementation of Constant Wind Speed Turbine Emulator Using Matlab/Simulink and FPGA

Design and Implementation of Constant Wind Speed Turbine Emu...

引用

9th International Conference on Ecological Vehicles and Renewable Energies (EVER)

作者： Moussa, Intissar Bouallegue, Adel Khedher, Adel Univ Sfax Renewable Energy & Elect Vehicles Lab ENIS Sfax Tunisia Univ Sousse SAGE Lab Adv Syst Elect Engn ENISO Riadh City 4023 Sousse Tunisia

ISBN: (纸本)9781479937875

In this paper we present the interests of the hardware implementation of control algorithms for constant wind speed turbine emulator based on DC-Machine. This system includes wind speed profile, mathematical model of a horizontal axis wind turbine, a separately excited DC-Machine and a fourth quadrant chopper. Modeling, simulation and implementation are realized in Matlab/Simulink environments. Unlike other works developed in this regards and through the tool XSG, algorithms will be implemented directly on FPGA. The features of this emulator are presented. Moreover, simulation results are analyzed and discussed using Simulink and XSG showing the benefits of our application.

关键词： control algorithms control regulators PI DC machine implementation on FPGA wind energy conversion systems wind turbine emulator

来源：评论

学校读者我要写书评

暂无评论

UNSTEADY LOADING OF ROTOR BLADES BY HIGH PRESSURE AIR INJECTION

引用

ASME International Mechanical Engineering Congress and Exposition

作者： Chi, John N. MIT Gas Turbine Lab Cambridge MA 02139 USA

ISBN: (纸本)9780791843833

A gas turbine engine consists of three primary components: a compressor, a combustion chamber, and a turbine. The operating range, performance, and reliability of gas turbine engines are limited by aerodynamic instabilities that occur in the compressor at low mass flow rates. Two of such compressor instabilities are rotating stall and surge. The stabilization of compression systems by means of active control has been demonstrated on several research compressors using different actuators such as inlet guide vanes, bleed valves, and air injection to manipulate the compressor flow field. This paper presents experimental and model simulated results of the steady and unsteady behaviors of air injection in high speed axial flow compressors that can be used for feasibility studies and control algorithm development. A control oriented model of the unsteady response of the transonic compressor blade rows to steady air injection is presented. This behavior was modeled by one-dimensional flow in a diffusing passage subject to a time varying inlet flow condition in the rotor relative reference frame. The one-dimensional model was then used to provide simplified input boundary conditions for a computational fluid dynamic (CFD) model that predicted aerodynamic loading on a transonic rotor blade due to steady air injection. The aerodynamic loading on a transonic rotor blade due to steady air injection were then simulated from the computational fluid dynamic (CFD) model. The simulation results for an evenly circumferentially spaced discrete number of jet actuators show that the fluctuating loading due to jet injection are non-sinusoidal and periodic. Total pressure, total temperature, and absolute flow angle survey measurements that map out the effect of high pressure air injection on a transonic compressor rotor for different levels of steady injection and different orientations are also presented.

关键词： control algorithms Simulation results Blades Combustion chambers Rotors Turbines Compression Reliability Computational fluid dynamics High pressure (Physics) Flow (Dynamics) Inlet guide vanes Surges Pressure Axial flow Gas turbines Compressors Temperature Valves Boundary-value problems Actuators

来源：评论

学校读者我要写书评

暂无评论

Performance Directed Energy Management for Main Memory and Disks

引用

ACM Transactions on Storage 2005年第3期1卷 346-380页

作者： Li, Xiaodong Li, Zhenmin Zhou, Yuanyuan Adve, Sarita University of Illinois at Urbana-Champaign Siebel Center for Computer Science Urbana IL 201 North Goodwin Ave. 61801 United States

Much research has been conducted on energy management for memory and disks. Most studies use control algorithms that dynamically transition devices to low power modes after they are idle for a certain threshold period of time. The control algorithms used in the past have two major limitations. First, they require painstaking, application-dependent manual tuning of their thresholds to achieve energy savings without significantly degrading performance. Second, they do not provide performance guarantees. This article addresses these two limitations for both memory and disks, making memory/disk energy-saving schemes practical enough to use in real systems. Specifically, we make four main contributions. (1)We propose a technique that provides a performance guarantee for control algorithms. We show that our method works well for all tested cases, even with previously proposed algorithms that are not performance-aware. (2) We propose a new control algorithm, Performance-Directed Dynamic (PD), that dynamically adjusts its thresholds periodically, based on available slack and recent workload characteristics. For memory, PD consumes the least energy when compared to previous hand-tuned algorithms combined with a performance guarantee. However, for disks, PD is too complex and its self-tuning is unable to beat previous hand-tuned algorithms. (3) To improve on PD, we propose a simpler, optimization-based, threshold-free control algorithm, Performance-Directed Static (PS). PS periodically assigns a static configuration by solving an optimization problem that incorporates information about the available slack and recent traffic variability to different chips/disks. We find that PS is the best or close to the best across all performance-guaranteed disk algorithms, including hand-tuned versions. (4) We also explore a hybrid scheme that combines PS and PD algorithms to further improve energy savings. © 2005, ACM. All rights reserved.

关键词： adaptation algorithms algorithms control algorithms Disk energy management lowpower design memory energy management multiple-power mode device performance guarantee

来源：评论

学校读者我要写书评

暂无评论

"RoboPress" - An automated mobile press for manufacturing concrete products

"RoboPress" - An automated mobile press for manufacturing co...

引用

3rd International Conference on Information Technology and Applications

作者： Adam, G Grant, E Lee, G Higher Tech Educ Inst Larissa Dept Telecom IT Larisa 41110 Greece

ISBN: (纸本)0769523161

This paper presents innovative manufacturing and control procedures applied in the design, construction and operation, of a mobile hydraulic press machine (RoboPress). The research demonstrates how the design of an automated mobile manufacturing system can be optimized through using qualitative modeling and simulation from artificial intelligence.

关键词： autonomous machines control algorithms qualitative modeling and simulation

来源：评论

学校读者我要写书评

暂无评论

Particle Swarm Optimization for Efficient Selection of Hybrid Electric Vehicle Design Parameters

Particle Swarm Optimization for Efficient Selection of Hybri...

引用

IEEE Energy Conversion Congress and Exposition (ECCE)

作者： Desai, Chirag Williamson, Sheldon S. Concordia Univ Power & Energy Res PEER Grp PD Ziogas Power Elect Lab Dept Elect & Comp Engn 1455 Maisonneuve Blvd W Montreal PQ H3G 1M8 Canada

ISBN: (纸本)9781424452873

It has been proven in literature that both the drivetrain as well as control strategy parameters have significant effects on the performance of hybrid electric vehicles (HEVs). A global optimization methodology based on particle swarm optimization (PSO) is presented in this paper for the parameter optimization of parallel hybrid electric drivetrain and control strategy simultaneously. The developed methodology aims at improvement in terms of fuel economy, without compromising driving performance. Simulation results show an improvement in the fuel economy, emissions, and overall drivetrain efficiency, which prove the potential of the optimization technique.

关键词： Battery control algorithms electric vehicles motor drives optimization

来源：评论

学校读者我要写书评

暂无评论

EXPERIMENTAL INVESTIGATION ON A CABIN-SUSPENDED CATAMARAN FOR WAVE ENERGY HARVESTING 41

EXPERIMENTAL INVESTIGATION ON A CABIN-SUSPENDED CATAMARAN FO...

引用

ASME 41st International Conference on Ocean, Offshore and Arctic Engineering (OMAE)

作者： Han, Jialin Li, Qiao Mochizuki, Akito Maeda, Teruo Itakura, Hiroshi Kitazawa, Daisuke Osaka Prefecture Univ Grad Sch Engn Osaka Japan Univ Tokyo Inst Ind Sci Kashiwa Chiba Japan Univ Tokyo Gratuate Sch Engn Kashiwa Chiba Japan Management Strategy Corp Yokohama Kanagawa Japan

ISBN: (纸本)9780791885888

Wave energy can be a significant factor in the progress towards a carbon-free society. This paper demonstrates the wave energy harvesting performance of a 1/2 scale cabin-suspended catamaran in regular head waves. The catamaran has a twinseater, the length is 3.28 m, and the width is 2.10 m. It consists of a suspended cabin, a suspension unit, and a twin-hull. One brushed DC Motor/Generator (M/G) coupled with one gearhead is set at each of the four corners of the cabin's deck. The shaft of the gearhead connects to a shaft of a pinion gear which meshes with a rack that is fixed on a hull through a ball joint. In this way, the vertical motion of the rack can be transferred into the rotational motion of the pinion causing the M/G generates electrical power. The power generation of the catamaran is experimentally investigated using a Maximum Power Point Tracking (MPPT) technique in a towing tank. Two control algorithms are developed: indirect MPPT and direct MPPT. It is found that the wave energy capture width ratio (CWR) obtained at the direct MPPT is approximately 11% higher than the indirect MPPT when their control parameters are having equal magnitude.

关键词： Wave energy Hull control algorithms Model basin Rotation Electricity (Physics) Engines Motors Waves Corners (Structural elements) Carbon Energy generation Gears Generators

来源：评论

学校读者我要写书评

暂无评论

Fiber-optical system for visualization of inner pipe defects by microrobot.

Fiber-optical system for visualization of inner pipe defects...

引用

Conference on Current Developments in Lens Design and Optical Engineering V

作者： Gradetsky, V Krabchuk, L Kniazkov, M Solovtsov, V Tulaikova, T Simakova, M Russian Acad Sci Inst Prob Mech Moscow 119526 Russia

ISBN: (纸本)0819454613

The control systems of the miniature robots are suggested for their motion over internal surfaces inside of the small diameter tubes. The mechanical system information-measuring sensor and control systems are considered. Three versions of the mechanical systems are suggested: electromagnetic, triad wheels and conversion of rotation motion to translation one. The electromagnetic mechanism use push pull tipe method for translation motion realization. Developed schemes in the modules design of control systems were checked experimentally on the robot's prototypes. Some results of the computer simulation illustrate the multilink robot control motion along the internal diameters of the tubes. This work was fulfilled under financial support of the Russian Found of Fundamental researches N 01-01-00913 and in frames of Federal Multi Purpose Scientific and Technical Program of Ministry of Industry, Science and Technologies: "Researches and Developments on priority directions of science and technology", "Knowledgeable basic investigations" block, "Basic investigations at the field of physics sciences" part Mechanics.

关键词： minirobot in-tube motion mechanical system control algorithms on-board microprocessor control schemes

来源：评论

学校读者我要写书评

暂无评论

PROPER ORTHOGONAL DECOMPOSITION OF HUSIR'S TEMPERATURE AND VELOCITY FIELDS

PROPER ORTHOGONAL DECOMPOSITION OF HUSIR'S TEMPERATURE AND V...

引用

8th ASME/JSME Thermal Engineering Joint Conference

作者： Chung, Kimberly H. DiCarlo, Anthony A. Mitre Corp Bedford MA 01730 USA

ISBN: (纸本)9780791854549

Thermal distortion is a critical design consideration for the Haystack Ultrawide-band Satellite Imaging Radar (HUSIR) with respect to its performance at W-band. This design consideration is needed due to the thermal distortion effects on the surface accuracy of a parabolic reflector. For example, a tight surface tolerance of similar to 100 microns root-mean-squared is required to obtain 85 percent antenna performance efficiency for the 37 meter (120 foot) diameter reflector. An understanding of the temperature and velocity fields aids compensation of these losses. Computational fluid dynamics models (CFD) are too computationally expensive to implement in a control algorithm. Therefore, this work applies proper orthogonal decomposition (POD) to simulated CFD data and creates a reduced order model of the fluid system that characterizes the dominant features of both the temperature and velocity fields. A case study of the HUSIR's convective flow inside a dome is illustrated.

关键词： control algorithms Flow (Dynamics) Temperature Imaging Fluids Satellites Design Domes (Structural elements) Principal component analysis Radar Computational fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：