开关电源的变频器、逆变器项目研发--DSP嵌入式电力电子系统-电力系统及自动化设计.doc

Simplified models of a single-phase power electronic inverter for railway power system stability analysisDevelopment and evaluation交通系统稳定性的简化仿真模型分析 电力电子逆变器的开发与评估方法Electric Power Systems ResearchUse of power electronic equipment has increased and introduced new dynamical phenomena in power systems. For example, new electric rail vehicles (locomotives) equipped with modern power electronic traction chains have caused situations of low-frequency power oscillations and instability in single-phase railway power supply systems. This paper presents the development and implementation of an instantaneous value model and simplified fundamental frequency (RMS) models of such an advanced electric rail vehicle in order to investigate their representation of low-frequency dynamics. The dynamical behaviour is studied by use of both time-domain simulations and linear analysis (eigenvalues) and the degree of simplifications regarding controller dynamics and power system dynamics are presented and discussed. An enhanced RMS model is tested in order to account for the impact of fast current dynamics on the low-frequency behaviour. The results show that this enhanced model is corresponding more closely to the instantaneous value model than what can be obtained by the traditional RMS simplifications and indicate that current dynamics should be included in stability studies involving power electronic inverters.Review of control techniques for inverters parallel operationThis paper presents state-of-the-art review of control methods applied currently to parallel power electronic inverters. Different system architectures, their modes of operation, management and control strategies will be analyzed; advantages and disadvantages will be discussed. Though, it is not easy to give a general view at the state of the art for the research area since it is rapid and going in different directions, this paper will focus on the main streams. This paper will start by briefly reviewing the current trends in power supply systems and the increasing importance for including power electronic devices. Next, the different techniques to parallel inverters suggested in the literature will be checked. These can be categorized to the following main approaches: master/slave control techniques, current/power sharing control techniques, and frequency/voltage droop control techniques. Finally, based on the reviewed state of the art, the study concludes by comparing the different approaches reported. In addition, their weaknesses and strengths are strained.Control of inverter-based micro-gridsThe predicted growth of small-scale non-50/60Hz power sources and the desire to be able to support loads independently of the public electricity grid requires the development inverter-based micro-grids. Power electronic interfaces have very different characteristics to conventional electrical machines and, therefore, different operation, control and protection schemes are required. Attention also needs to be given to the dominance of single-phase harmonically distorting loads in some networks and control schemes put in place that maintain voltage quality. A control scheme that exploits the controllability of inverters to operate a micro-grid and provide good power quality is examined and compared with both traditional power systems and with control of dc/dc power converters. The limitations of communication and control bandwidth are discussed. Experimental results are used to illustrate the performance that can be achieved with various combinations of linear and non-linear, three-phase and single-phase loads.基于变频功能的微电网/独立式电网/区域电网控制实施与研究Quality-driven model-based architecture synthesis for real-time embedded SoCsSystems ArchitectureThe recent spectacular progress in modern microelectronics created a big stimulus towards development of embedded systems. Unfortunately, it also introduced unusual complexity which results in many serious issues that cannot be resolved without new more adequate development methods and electronic design automation tools for the system-level design. This paper discusses the problem of an efficient model-based multi-objective optimal architecture synthesis for complex hard real-time embedded systems, when using as an example a system-level architecture exploration and synthesis method that we developed.系统结构与架构学学报基于质量驱动模型的结构分析与实施嵌入式控制/反馈/仿真软件方法Research and development of maximum power transfer tracking system for solar cell unit by matching impedanceRenewable EnergyEmploying the theorem that matching impedance produces maximum power transfer, the current study develops a low-cost and highly efficient “maximum power point tracker for a solar cell unit,” for the purpose of allowing a solar cell to achieve optimal power transfer under different solar intensities and temperatures. Circuit control takes a single-chip microprocessor as the core and the booster circuit design undergoes the solar cell charging operation even though the solar cell output voltage is lower than the rated storage battery voltage. Experiments conducted in this study prove that the tracker this study develops effectively enhances the utilization efficiency of a solar cell. When a solar cell is at an output voltage above 30% of the rated voltage, it can charge a storage battery. When it reaches above 80% of the rated voltage, its power conversion efficiency can reach above 85%. The charge and discharge management mechanism of the device also avoids excessive charge and discharge of the storage battery, and extends storage battery longevity.A review of power converter topologies for wind generators大型/中型/小型风力发电机用逆变器/变频器技术回顾与总结反思Wind energy conversion systems have become a focal point in the research of renewable energy sources. This is in no small part due to the rapid advances in the size of wind generators as well as the development of power electronics and their applicability in wind energy extraction. This paper provides a comprehensive review of past and present converter topologies applicable to permanent magnet generators, induction generators, synchronous generators and doubly fed induction generators. The many different generatorconverter combinations are compared on the basis of topology, cost, efficiency, power consumption and control complexity. The features of each generatorconverter configuration are considered in the context of wind turbine systems.Revival by automation of induction generator for distributed power systems, in Romanian academic research改进型的自动化导航式分布电力系统发电机 学术研究的开发阶段The paper approaches the half-century history and the main research results of the academic staff and researchers from “Politehnica” University of Timisoara (Universitatea “Politehnica” TimisoaraUPT) and their collaboration with the academic, research and production environment concerning the use of induction machine as power supply in microhydro plants and windmills in particular; from among these collaborators we mention: The Romanian AcademyTimisoara Branch, The Institute for Automation IPATimisoara Branch, The Research and Modernization Institute for Energetics ICEMENERG Bucharest, The National Institute for Heat Engines INMT Bucharest, The Machine Construction Works UCMRResita, “Electroputere” WorksCraiova and “Electromotor” WorksTimisoara. The paper aims at presenting the original research results at UPT against the background of general research from all over the world focused on revival the induction generator by automation.Front-end electronics and trigger systemsStatus and challengesNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentThe past quarter century has brought about a revolution in front-end electronics for large-scale detector systems. Custom integrated circuits specifically tailored to the requirements of large detector systems have provided unprecedented performance and enabled systems that once were deemed impossible. The evolution of integrated circuit readouts in strip detectors is summarized, the present status described, and challenges posed by the sLHC and ILC are discussed. Performance requirements increase, but key considerations remain as in the past: power dissipation, material, and services. Smaller CMOS feature sizes will not reduce the power required for the desired noise levels, but will improve digital power efficiency. Significant improvements appear to be practical in more efficient power distribution. Enhanced digital electronics have provided powerful trigger processors that greatly improve the trigger efficiency. In data readout systems, they also improve data throughput, while reducing power requirements. Concurrently with new developments in high energy physics, detector systems for cosmology and astrophysics have made great strides. As an example, a large-scale readout for superconducting bolometer arrays is described.核电用电力电子、电力系统及自动化设备 电子电路的功率放大循环智能化供电系统：能量储备电池 储能与户用新能源供电/家庭取暖装置Intelligent uninterruptible power supply system with back-up fuel cell/battery hybrid power sourceThis paper presents the development of an intelligent uninterruptible power supply (UPS) system with a hybrid power source that comprises a proton-exchange membrane fuel cell (PEMFC) and a battery. Attention is focused on the architecture of the UPS hybrid system and the data acquisition and control of the PEMFC. Specifically, the hybrid UPS system consists of a low-cost 60-cell 300W PEMFC stack, a 3-cell leadacid battery, an active power factor correction acdc rectifier, a half-bridge dcac inverter, a dcdc converter, an acdc charger and their control units based on a digital signal processor TMS320F240, other integrated circuit chips, and a simple network management protocol adapter. Experimental tests and theoretical studies are conducted. First, the major parameters of the PEMFC are experimentally obtained and evaluated. Then an intelligent control strategy for the PEMFC stack is proposed and implemented. Finally, the performance of the hybrid UPS system is measured and analyzed.Photovoltaic scavenging systems: Modeling and optimizationMicroelectronics 微电子学学报太阳能系统发电效能/效率/转化率的建模与优化The interest in embedded portable systems and wireless sensor networks (WSNs) that scavenge energy from the environment has been increasing over the last years. Thanks to the progress in the design of low-power circuits, such devices consume less and less power and are promising candidates to perform continued operation by the use of renewable energy sources. The adoption of maximum power point tracking (MPPT) techniques in photovoltaic scavengers increases the energy harvesting efficiency and leads to several benefits such as the possibility to shrink the size of photovoltaic modules and energy reservoirs. Unfortunately, the optimization of this process under non-stationary light conditions is still a key design challenge and the development of a photovoltaic harvester has to be preceded by extensive simulations. We propose a detailed model of the solar cell that predicts the instantaneous power collected by the panel and improves the simulation of harvester systems. Furthermore, the paper focuses on a methodology for optimizing the design of MPPT solar harvesters for self-powered embedded systems and presents improvements in the circuit architecture with respect to our previous implementation. Experimental results show that the proposed design guidelines allow to increment global efficiency and to reduce the power consumption of the scavenger.Transform-domain and DSP based secure speech communication system基于DSP的工作场合、近距离户外活动对讲装置设计 时/频域互换 安全保密 通话稳定性Microprocessors and Microsystems 微处理器和微系统学学报Secure speech communication has been of great significance in civil, commercial and particularly in military communication systems. Speech scramblers play a major role in these systems and transform-domain, specially, DCT (Discrete Cosine Transform) based encryption of speech has often been a preferable choice for researchers and engineers. In such systems, besides security, removal of redundant information and the execution speed of the algorithms have also been the main focus of research and exploration. In this paper, we concentrate on the investigation of these three parameters in general and security and speed in particular. In this research these attributes are envisaged by exploiting ITU-T G.723.1 speech codec, DCT based speech encryption algorithm and Texas Instruments 32-bit floating-point DSP (Digital Signal Processor) TMS320C6711, respectively. This work, in fact is a continuation and an advancement of the work carried out by Jameel et al. A. Jameel, M.Y. Siyal, N. Ikram, A Robust Secure Speech Communication System using G.723.1 and TMS320C6711 DSP, Microprocessors and Microsystems 30 (1) (2006) 2632. in which they presented a redundancies-free, secure and fast speech communication system using G.723.1 codec, time-domain speech scrambling techniques and Texas Instruments TMS320C6711 DSP. On the contrary, in this exploration the same system is improved significantly in terms of security and speed. In order to reduce residual intelligibility thereby to enhance security a new DCT based algorithm using sub-framing and lookup table is proposed, implemented and analyzed. In terms of speed, the reference code of G.723.1 is further optimized on advanced level. Additionally, the schemed is designed in such a way that it also diminishes talk spurt and intonation present in the original speech signal which, as a result, increases the level of security. Hence a redundancies-free, secure and high speed communication system has been proposed, implemented and analyzed using various types of speech segments. The results show that the proposed system is suitable for real-time civil, commercial and military applications.Study of a multiphase interleaved step-up converter for fuel cell high power applications大功率公交车/供电站的储能/备用燃料