发布时间 : 星期日 文章Heat transfer—A review of 2005 literature更新完毕开始阅读0c0f94707fd5360cba1adbaa
Efficient design and simulation of an expandable hybrid (wind–photovoltaic) power system with MPPT and inverter input voltage regulation features in compliance with electric grid requirements Review Article Electric Power Systems Research
In this paper an efficient design along with modeling and simulation of a transformer-less small-scale centralized DC—bus Grid Connected Hybrid (Wind–PV) power system for supplying electric power to a single phase of a three phase low voltage (LV) strong distribution grid are proposed and presented. The main components of the hybrid system are: a PV generator (PVG); and an array of horizontal-axis, fixed-pitch, small-size, variable-speed wind turbines (WTs) with direct-driven permanent magnet synchronous generator (PMSG) having an embedded uncontrolled bridge rectifier. An overview of the basic theory of such systems along with their modeling and simulation via Simulink/MATLAB software package are presented. An intelligent control method is applied to the proposed configuration to simultaneously achieve three desired goals: to extract maximum power from each hybrid power system component (PVG and WTs); to guarantee DC voltage regulation/stabilization at the input of the inverter; to transfer the total produced electric power to the electric grid, while fulfilling all necessary interconnection requirements. Finally, a practical case study is conducted for the purpose of fully evaluating a possible installation in a city site of Xanthi/Greece, and the practical results of the simulations are presented.
Article Outline
1. Introduction
2. Configuration and modeling of a small-scale centralized DC—bus GCHWPPS via Simulink/MATLAB 2.1. Solar and wind potential analysis of a selected (candidate) installation site 2.2. Photovoltaic Subsystem
2.2.1. Photovoltaic generator (PVG) model
2.2.2. Buck-Boost DC–DC Converter (BBC1 and BBC2) models 2.2.3. Control unit (DSP1) of the PVS
2.3. Wind Energy Conversion Subsystem 2.3.1. Wind turbine model
2.3.2. Permanent magnet synchronous generator (PMSG) model 2.3.3. Embedded uncontrolled diode bridge rectifier model 2.3.4. Buck-Boost DC–DC Converter (BBC3 and BBC4) models 2.3.5. Control unit (DSP2) of the WECS 2.4. Power decoupling capacitor (CPD)
2.5. Necessary requirements (rules) for connecting a HWPPS to the Greek LV distribution grid 2.5.1. Electric grid model 2.5.2. Inverter model
2.5.3. Control unit (DSP3) of the inverter 3. Case study
3.1. Solar and wind potential analysis of the selected site in Xanthi, Greece 3.2. Simulation results 4. Conclusions
Appendix A. List of symbols Appendix B. Fuzzy rules References
Software design specification and analysis technique (SDSAT) for the development of safety-critical systems based on a programmable logic controller (PLC) Original Research Article
Reliability Engineering & System Safety
This paper introduces a Software Design Specification and Analysis Technique (SDSAT) for
safety-critical systems based on a Programmable Logic Controller (PLC). During software development phases, the design phase performs an important role in connecting the requirements phase and the implementation phase, and it is a process of translating software requirements into software structures. In this work, the Nuclear FBD-style Design Specification and analysis (NuFDS) approach was proposed for nuclear Instrumentation and Control (I&C) software. The NuFDS approach is suggested in a straightforward manner for effective and formal software design specification and analysis. Accordingly, the proposed NuFDS approach is composed of a software design specification technique and a software
design analysis technique. In addition, for tool support in the design phase, we developed the NuSDS tool based on the NuFDS approach; this tool is used specifically for generating software design specification and analysis for nuclear fields.
Article Outline
1. Introduction
2. Software design specification and analysis technique (SDSAT) 2.1. Design specification of the NuFDS approach 2.1.1. Database specification 2.1.2. Architecture specification 2.1.3. Behavior specification
2.1.4. Hardware configuration specification 2.2. Design analysis of the NuFDS approach
2.2.1. Software architecture analysis technique (SAAT) 2.2.2. Software behavior analysis technique (SBAT) 3. The NuSDS tool 4. Application
4.1. BP design using the NuFDS design specification 4.2. Software architecture analysis based on SAAT 4.3. Software behavior analysis based on SBAT 5. Conclusion Acknowledgements References
Design and application of the technical training set for plc- based power supply unit developed for industrial applications Original Research Article Procedia - Social and Behavioral Sciences
Design and control of a prototype training set, which especially the students studying in institutions offering education at undergraduate and associate levels can employ as a PLC (Programmable Logic Controller)-controlled simulator of the power supply unit of electroerosion machinery (electrical discharge machinery) that are used frequently during industrial manufacturing processes, has been actualized through this work, for the purpose of training qualified technical personnel needed by companies, who
are specialized in control and electromechanics. The training set, therefore, contributes to a large extent to the training process in favor of faculty members, who are to train personnel for the sector, and in favor of students, who should be able to acquire proper education. Working on the prototype allows students to acquire knowledge and practical skills and then make use of those skills for maintaintenance, repair and control of machinery.
Heat transfer—A review of 2004 literature Review Article International Journal of Heat and Mass Transfer
The present review covers the heat transfer literature published in 2004 in English language, including some translations of foreign language papers. Though extensive, some selection is necessary. Only articles published by a process of peer review in archival journals are reviewed. Papers are grouped into subject-oriented sections and further divided into sub-fields. Many papers deal with the fundamental science of heat transfer, including experimental, numerical and analytical work; others relate to applications or natural systems. In addition to reviewing journal articles, this Review also takes note of important conferences and meetings on heat transfer and related areas, major awards presented in 2004, and relevant books published in 2004.
Article Outline
Foreword 1. Introduction A. Conduction
B. Boundary layers and external flows C. Channel flows D. Separated flows
DP. Heat transfer in porous media E. Experimental methods
F. Natural convection—internal flows FF. Natural convection—external flows G. Rotating flows
H. Combined heat and mass transfer I. Bioheat transfer
J. Change of phase—boiling and evaporation