A computer-aided teaching package for microprocessor systemseducation

A computer-aided teaching (CAT) package for use in a microprocessor systems course is described. It uses the Z80 CPU as the basis for describing how an eight-bit CPU functions internally and as the master of a microcomputer system. The package, which consists of an assembler and a graphics simulator, aids as a powerful teaching tool that enables the student to learn about the internal architecture of a microprocessor as applied to the Z80 CPU and its instruction set with a step-by-step graphics animation of the instruction execution and timing. The package allows the user to execute a program step by step and to test the operation of the internal registers, buses, and memory contents at every clock edge. It also simulates read/write cycles from/to memory and input-output devices. Finally, it allows the user to write and debug problems at the assembly language or machine code level. The package is menu driven, interactive, flexible, and user-friendly     

动力环境监控系统的应用

介绍了通信电源系统的架构,分析了影响电源系统正常工作的5个主要因素,重点介绍了动环监控系统的网络架构和监控对象,并分析了其在通信电源系统日常运行维护中的作用。     

交互式电话会议系统在青海电力中的应用

在对青海电力系统先后使用的汇接式电话会议系统和交互式会议电话系统在接入方式、会议模式、通话效果等方面进行比较的前提下,充分肯定了交互式电话会议系统的两大优势:即通过提供一个全新的自由开放式语音会议通信平台,可以使与会者随时随地通过手中的话机参与会议,同时也为电力突发事件(如电力故障的分析、处理)提供了适时、便捷的会议召集手段。文中还介绍了交互式电话会议系统的网络结构、应用模式和在青海电力系统中的应用情况。     

超级电容储能在独立供电系统中的应用设计

近年来为克服常规能源的有限性和分布不均匀性,太阳能作为一种清洁的可再生能源,日益被独立供电系统所看重.而超级电容作为新生电能存储器件以其优势走进人们视野.采用C8051 F320做控制芯片,以太阳能最大功率跟踪技术为依托,探求超级电容在独立供电系统中的储能应用.     

穿戴式移动音视频交互系统在电力生产中的应用

介绍了穿戴式移动音视频交互系统建设的整体方案和结构,并从硬件构成和软件设计两方面进行了具体的阐述,总结了系统的技术特点,最后通过在220 kV宣州集控站的实地应用案例,总结分析了系统的应用价值和在保障电力安全生产工作中所发挥的效益.     

水火并有独立发电企业日前优化运行研究

电力市场环境下,水火并有独立发电企业在满足区域电网公司下达负荷任务的同时,整个企业的短期(日)运行费用最小是目前亟待研究的问题.从发电企业的角度出发,采用人工免疫系统建立优化模型进行问题求解,将该模型运用在某独立发电企业仿真中,通过日前现货市场计算,结果表明系统水火互补特征明显,约束条件完全满足,较大地节约了全系统的日运行费用.     

A personal computer based interactive software for power systemoperation education

The use of personal-computer-based interactive software to aid instruction in power system operations is described. The software was designed to be used as a teaching aid for the course power system operation at National Taiwan University. The main programs included in the package were short-term load forecasting and unit commitment. Other supporting routines included power flow analysis, static security assessment, small signal stability analysis, and transient stability analysis. To promote the students interest in the course, a user-friendly interface and interactive windows have been developed. The integrated software package proved to be useful for educational and research purposes     

Algorithms for control of buffer power supply for independent vehicle

It is proposed to use the buffer power supply to increase the power efficiency of an accumulator vehicle. Control algorithms that serve to increase the time between charging an independent electric vehicle are considered.     

Generators for independent power plants: performance and trends

Modern trends in designing generators for independent power plants require mass and volume reduction by means of increasing electromagnetic load. Conflicts arise with operational requirements regarding voltage drop limitation under sudden load increase. Practical methods to solve the problem at the present stage of generator design and manufacture are suggested. Several methods are outlined to limit generator reactances by selecting electromagnetic load levels, as well as choosing the geometry of stator teeth zone, of rotor poles, of damper winding. Besides, the problem of asynchronous motor starting from generators of independent power plants, working at no-load prior to the starting of the motor has been investigated in the article. Some additions to the standards for independent generators are proposed.     

A hierarchical interactive approach to electric power systemrestoration

The control problem of a power system which is operating in a restorative state, i.e., a power system that has lost some of its load and/or has separated into electrical islands as a result of a major system disturbance, is addressed. By means of a hierarchical interactive approach, this control problem is decomposed into three layers or time-hierarchies i.e., adaptive, optimizing, and direct. Restorative control actions are then determined and executed by the appropriate layer according to the time frame available for doing so. The authors describe the restoration control problem in power systems, and provide the conceptual details of the hierarchical interactive approach proposed for its solution     

可扩展的电力系统故障集成分析环境

随着我国电力系统的快速发展,各种故障分析算法层出不穷,对故障分析软件提出了越来越高的要求,然而目前国内的主要录波器和电力综合自动化设备提供商提供的专业分析软件,其公式编辑器环境相当简陋,且算法较为单一,不支持算法库的动态扩展,针对这种现状,采用设计模式的思想、插件技术和先进的C 模块库:STLPORT、BOOST实现了一个通用的电力故障集成分析环境,系统内集成了大量的通用电力算法库,并且采用插件技术实现了分析算法的可扩展性。     

可扩展的电力系统故障集成分析环境

随着我国电力系统的快速发展,各种故障分析算法层出不穷,对故障分析软件提出了越来越高的要求,然而目前国内的主要录波器和电力综合自动化设备提供商提供的专业分析软件,其公式编辑器环境相当简陋,且算法较为单一,不支持算法库的动态扩展,针对这种现状,采用设计模式的思想、插件技术和先进的C + +模块库:STLPORT、BOOST实现了一个通用的电力故障集成分析环境,系统内集成了大量的通用电力算法库,并且采用插件技术实现了分析算法的可扩展性.     

面向电力培训的三维交互仿真平台的设计与实现

针对电力三维交互仿真培训系统的运行和开发需求,设计和开发了基于XNA Framework的三维交互仿真平台PowerX.PowerX支持大规模三维虚拟场景实时渲染,能够很好地呈现具有仿真对象数量众多、虚拟设备三维模型精细以及操作状态实时动态变化等特点的电力仿真培训三维虚拟场景;同时PowerX设计并实现了支持操作者开放式操作行为的复杂操作交互过程逻辑控制,允许操作者根据自我认知进行自由的模拟操作,使电力仿真培训系统更加符合真实操作情境及满足培训要求.配电运行仿真培训系统的开发实例表明,PowerX能够简化系统三维视景仿真的开发复杂度,并且支持复杂操作过程控制逻辑的实现,使系统的仿真功能更符合现场实际状况、更贴近培训需求.     

不确定性环境下园区风光储互动运行的PPO强化学习策略

随着能源结构的不断升级,部署有新能源发电的新型园区将在未来新型电力系统中扮演重要的角色。需求的随机性、风光出力的间歇性、电力市场电价的波动性等不确定性因素耦合在一起,使得风光能源与电池储能系统的合理互动运行变得十分困难。考虑到传统优化方法的局限性,提出了一种基于PPO算法的深度强化学习方法,用于解决不确定环境下园区风光储互动运行问题。基于强化学习的理论框架,为园区互动运行构建了一个具有连续状态空间和连续动作空间且转移概率未知的马尔可夫决策模型,通过与新型负荷控制系统对接的能源管理系统控制园区微电网中的电池储能系统及柔性资源,在充分考虑电池退化成本的基础上,实现园区经济运行。     

A method of single-phase PWM for an independent power supply in photovoltaic power generation systems

We propose a method of single-phase PWM for an independent power supply in photovoltaic power generation systems. This new PWM is derived by comparing levels of signal waves with one of carrier waves which have bipolar swing different from unipolar swing in the conventional PWM. In this PWM, we can use a battery with lower voltage in combination with the photovoltaic power generation; fundamental level of output voltage is raised by about 11%, though poor in quality of waveforms. © 1998 Scripta Technica. Electr Eng Jpn, 122(4): 55–62, 1998     

A fast solution method for multiobjective optimal power flow using an interactive approach

In modern industrialized societies, it is mandatory to provide an uninterrupted supply of high-quality electric energy at modest cost while promoting a better environment. This can only be realized through very sophisticated power system operations that compromise several contradictory factors, namely, economy, security and environment. Since these factors are in trade-off relationships to each other, they should be analyzed appropriately. One class of problems that simultaneously satisfy several criteria in trade-off relationships is called “multiobjective optimization problems.” Optimal power flow (OPF) has been regarded as the most powerful means to obtain effective system operation plans since it only optimizes a single objective function. This paper proposes an efficient solution methodology for a class of multiobjective optimal power flow problems which makes use of a heuristic search method. An optimal solution can be found in the proposed heuristic search method based on local information about a preference index, which is chosen arbitrarily from a given set of objectives. This circumvents the exhaustive evaluation of all noninferior solutions needed in the existing multiobjective OPF algorithm proposed by the authors, thus dramatically reducing the solution time. The proposed method has been coded and applied to the IEEE 57 node test system. Simulation results have demonstrated the possibility of utilizing this method in on-line environments.     

考虑交互功率与可再生能源功率波动的微电网调度优化模型

电动汽车的发展普及与V2G (Vehicle to Grid)思想的提出,对微电网系统的经济、安全运行带来了新的挑战,如何合理调度电动汽车有序充放电,促进微电网的经济、平稳运行成为当下的研究热点。针对含电动汽车的风光储并网型微电网环境,构建了最小化微电网与外部电网交互功率和平抑可再生能源功率波动的多目标调度优化模型。通过对某商业区域微电网运行算例的仿真求解,从微电网运行经济效益、日交互电量以及出力功率平均变化量等方面验证了所建模型的合理性和正确性。算例结果表明,以微电网为平台集成利用具有一定出行规律的电动汽车与可再生能源是一种理想的协同利用模式,既可以提高微电网运行的经济效益,又能有效改善微电网的交互功率和出力波动。     

市场环境下的负荷备用容量

经济利益是市场环境下电网公司所追求的重要目标之一。利用概率统计方法，对切负荷措施的可行性、保留负荷备用容量成本及切负荷赔偿费用进行了分析，提出市场环境下负荷备用容量的确定应在综合考虑保留备用容量成本和切负荷赔偿费用的基础上，求取经济上最优的负荷备用容量。数字份真结果表明方法可行，且具有较好的经济性。     

一种带电压前馈的适用于独立小电网系统的有源电力滤波器控制策略

独立小电网中电压波动比较剧烈,用于大电网系统的传统有源电力滤波器在独立小电网工况下不能很好地工作.针对这种情况,本文分析了电压波动对有源电力滤波器的影响,并提出了带电压前馈的有源电力滤波器控制策略,通过电压前馈环节的引入彻底地消除了电压波动对有源电力滤波器的影响.最后通过实验验证了带电压前馈的有源电力滤波器具有较好的静态补偿效果,且对电网电压波动不敏感,完全可以应用于电压波动比较剧烈的独立小电网系统.     

Application of information system technologies to power control centers in a liberalized environment

This paper describes the new control centers that are incorporated with information system technologies to handle precise security margins on a wide level and secure information exchange between system operators and other actors emerging in the liberalized electric power supply environment in progress. To further realize the system stress analysis by high‐speed processing, symmetric multi processor (SMP) servers are adopted through cost‐effective performance from the standpoint of investment protection. The performance improvements and observations are shown with processing time measurements according to the peculiarity of the power system analysis software packages embedded in the client‐server‐based energy management system (EMS). To cope with malicious intrusions into the cyber space through data links with outside information systems, an information exchange method using tough Internet protocol (IP) separation between information system and control system portions is also presented using a practical example, with cyber security strictly maintained among the other internal information systems in an electric power utility. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.