高速电气化铁路新型电能质量补偿系统

针对高速电气化铁路牵引供电系统面临的谐波电流含量高且较分散、负序电流大的电能质量问题,建立一种新型电能质量补偿系统。该系统主要由电气化铁路功率调节器、两组晶闸管控制电抗器和两组晶闸管控制3次滤波器组成,其中电气化铁路功率调节器只用来转移有功功率和治理部分谐波,3次滤波器用于滤除3次谐波和改变供电臂电流相角,电抗器也用来改变供电臂电流相角。该系统以最小的有源容量和较低的成本进行谐波抑制和负序电流补偿。本文在阐述其工作原理的基础上,建立了其基波域和谐波域的统一等效电气模型,并深入研究了其负序补偿和谐波抑制原理,分析了电气化铁路功率调节器最佳容量选取的原则,同时还对整个系统的谐振特性进行了分析,并模拟京沪高速电气化铁路实际供电系统进行了仿真,仿真结果验证了本文研究内容的正确性和有效性。     

电网可视化技术

电力系统互联区域的扩大和市场竞争的引入，使电力系统的运行日趋复杂，关心系统运行特性的机构也有所变化和增加。如何生动、明了地显示系统运行信息并予以共享，就是电网可视化技术要解决的问题。文中详细介绍美国北美电力可靠性委员会(NERC)所辖区域采用电网可视化技术的思路，涉及线路潮流可视化、电网特性数值轮廊线的绘制及三维空间表示法、输电线路数据图等内容。     

电力系统无功优化在线计算的算法研究

通过在线无功优化,降低网损、保证电压质量,对供电企业的经济运行是非常必要的。文章针对此问题就无功优化方法中具有代表性且差异较大的两种方法——内点法和遗传算法进行研究和比较,在IEEE30节点系统中进行实例计算,比较这两种算法在收敛性能、计算速度、对离散变量的处理等方面的优劣性,给出了两种算法相结合的无功优化算法,得到了比较满意的结果。     

Simulation Techniques for Rural Electric Power Systems Planning

This paper introduces an effective method for rural electrical systems planning. All three-phase, two-phase, and single-phase lines are simulated in one computer study. Typical load flow results are obtained from the study. The method emphasizes simplicity and flexibility. Very little computation time is required. Once the data are prepared the amount of work required to incorporate the changing of the system is small and very inexpensive. This type of flexibility is one of the most important contributions of this new method. The method applies to both long-range and short-term system planning.     

广域电力系统负荷整体建模方法

针对广域电力系统中负荷节点面广量大的特点,明确了广域电力系统负荷建模的思路,即充分利用广域测量信息来建立系统化评价指标,探索广域多点同步确定负荷模型参数的方法,对节点分类,对参数分级。提出了广域电力系统负荷建模的方法,即确定负荷节点分类的特征变量,进行负荷节点分类,建立系统化指标,辨识负荷参数。通过仿真算例,验证了多负荷节点同步建模的可能性和所提出的方法的有效性。最后对广域电力系统负荷建模进一步研究的内容提出了建议。     

Corrosion Control in Electric Power Systems

The electrochemical mechanism of aqueous corrosion is outlined, and it is demonstrated that the process depends on a complex interaction between the material and its environment given the particular circumstances of exposure. Failure to recognize the full implications of the environment or the circumstances will often lead to unexpected corrosion failure. The technique for controlling corrosion are subdivided into material selection, coatings, electrical insulation, cathodic protection, etc. Each technique is described and explained. The need to apply a considered corrosion control package, rather than the use of a single technique, is stressed.     

电力系统短期预报频率控制

随着火电厂的DCS系统和水电厂的计算机实时控制系统的广泛应用 ,如何发挥其优势以提高电力系统的稳定、可靠及高质量的运行 ,越来越引起人们的重视。本文对主调频水电站进行系统频率短期预报 ,并把预报结果直接应用于水电站的计算机频率控制。文中建立了频率调整的辨识模型、频率预报模型和主调频电站的有功出力控制模型 ,并分析了计算机仿真结果。     

电力电子技术及在电力系统中的应用现状及前景

介绍了电力电子技术的发展和在电力系统发电、输电、配电等各系统中的应用,并预测了其发展趋势及在电力系统中的应用前景。     

Power Conversion and Control for Fuel Cell Systems in Transportation and Stationary Power Generation

Abstract—Fuel cells are being explored for several applications, such as transportation, microgrids, back-up power, grid-connected and stationary power generation, portable appliances, etc. Fuel cells are preferred because of their secured and continuous output, zero or low emissions, and high efficiency. This article presents a review of the power conversion and control strategies for fuel cell systems for transportation and stationary power generation. The control characteristics and properties of fuel cells being used in these applications are discussed. A few power conversion system architectures for propulsion and power generation are presented. The present status and future strategies for advancement of fuel cell based systems are also presented.     

电力信息系统建模和定量安全评估

提出一种用于电力信息系统安全设计的建模语言和定量化评估方法。设计了安全体系设计迹语言,统一描述系统结构、系统业务、安全策略、攻击行为和安全措施等;构造了风险自动分析算法,以获得电力信息系统的攻击迹;基于攻击迹提出相对安全度概念,用于定量评估安全体系的安全性;通过实例验证了所述方法的有效性。该方法可用于定量评估各类安全措施的控制效果,如增加新的安全功能、调整系统自身结构和用户业务需求等,减少了选择安全措施的主观性。     

电动汽车与电力系统的交互作用

发展电动汽车产业已成为许多国家应对能源危机和环境污染这两大难题的战略选择, 可入网电动汽车的规模化应用会对电力系统的多个方面带来新的问题甚至挑战。在此背景下, 首先介绍动力电池的研究现状和发展动向, 详细评述现有考虑时空分布的电动汽车集群负荷特性方面的研究进展。之后, 阐述电动汽车规模化应用对电力系统多方面可能带来的影响与挑战, 着重分析电动汽车接入对配电系统的影响, 电动汽车与电力系统的交互与协调问题, 概述对电动汽车充放电管理以改善电力系统运行的安全性与经济性的可能途径。最后, 从用户侧和系统侧简要评述大量电动汽车与电力系统交互所能带来的经济价值。     

基于强夯与强夯置换法的电厂地基处理

针对某电厂饱和软粘土的特殊地质条件,分别采用强夯与强夯置换法进行了地基加固处理。详细介绍了设计方案,通过平板载荷试验、超重型动力触探试验、密实度试验等检测方法对地基加固效果进行综合评价分析,进一步验证了强夯与强夯置换法的适用条件,对此类工程的地基加固处理具有一定的参考意义。     

Analysis of tools for simulation of Shipboard Electric Power Systems

Navy Shipboard Power Systems have different characteristics when compared with utility power systems. To conduct system studies on shipboard power systems, an effective simulation tool is required to model the Shipboard Electric Power Systems. This paper presents the results of the analysis of three popular simulation tools, ATP, PSpice and Saber for transient simulation of Shipboard Electric Power Systems (SPSs). The results suggest that ATP is a good tool for generating detailed component models and calculating model parameters directly from standard specifications and ratings of the equipment. PSpice and Saber have an excellent graphical interface for building complex SPSs and flexibility in establishing monitoring points and processing output data.     

Optical Voltage and Current Measuring System for Electric Power Systems

Recently, optical voltage and current measuring methods based on a principle different from that of the existing apparatus have been developed. As the most promising method among them, a voltage measuring method which uses an electrooptic effect called the Pockels effect and a current measuring method which uses a magnetooptic effect called the Faraday effect have been proposed. The authors have developed an optical voltage measuring system based on the electrooptic effect in bismuth germanium oxide Bi4Ge3O12 and a current measuring system based on the magnetooptic effect of borosilicate crown glass for the purpose of utilization in electric power systems. As a result of the development, high accurate voltage and current measuring systems such as non linearity error less than ±0.4% and temperature stability less than ±1.0% were obtained. Furthermore, short-circuit current was measured with the current measuring system, and an accuracy within 0 to -4% in the range of 30 kApeak to 150 kApeak was obtained. When the measuring systems were mounted on the model of 70 kV class gas insulated switchgears, it was verified that the measuring systems had satisfactory linearity and temperature stability.     

On Power Quality of Variable-Speed Constant-Frequency Aircraft Electric Power Systems

In this paper, a comprehensive model of the variable-speed constant-frequency aircraft electric power system is developed to study the performance characteristics of the system and, in particular, the system power quality over a frequency range of operation of 400 Hz to 800 Hz. A fully controlled active power filter is designed to regulate the load terminal voltage, eliminate harmonics, correct supply power factor, and minimize the effect of unbalanced loads. The control algorithm for the active power filter (APF) is based on the perfect harmonic cancellation method which provides a three-phase reference supply current in phase with its positive-sequence fundamental voltage. The proposed APF is integrated into the model of a 90-kVA advanced aircraft electric power system under VSCF operation. The performance characteristics of the system are studied with the frequency of the generator's output voltage varied from 400 Hz to 800 Hz under different loading conditions. Several case studies are presented including dc loads as well as passive and dynamic ac loads. The power quality characteristics of the studied aircraft electric power system with the proposed active filter are shown to be in compliance with the most recent military aircraft electrical standards MIL-STD-704F as well as with the IEEE Std. 519.     

Methods for Improving the Quality of Electric Power in the Unified Marine Power Systems

At present, the unified electric-power systems using multilevel converters, Azipod systems, various types of screw-rotor columns, and new types of electric motors have become widespread. These power systems make it possible to provide high quality of consumed power, as well as to increase the reliability and maneuverability of marine vessels. In this paper, the requirements for modern unified electric-power systems and the methods to control electricity parameters have been considered.     

超导材料在电力系统中的应用

在电力系统中采用超导技术,可扩大电网的输送容量,降低传输损耗,提高系统运行的稳定性和可靠性,改善电能质量,并有利于保护环境。超导材料的发展促进了超导应用技术的发展,超导技术在电力系统中具有非常广阔的应用前景,是21世纪电力科学技术最具发展潜力的应用之一。超导材料在超导电缆、超导变压器、超导电机、超导故障电流限制器、超导储能器等超导电力设备中的实用化将把电力科技的发展带入一个崭新的阶段。     

Severe Multiple Contingency Screening in Electric Power Systems

We propose a computationally efficient approach to detect severe multiple contingencies. We pose a contingency analysis problem using a nonlinear optimization framework, which enables us to detect the fewest possible transmission line outages resulting in a system failure of specified severity, and to identify the most severe system failure caused by removing a specified number of transmission lines from service. Illustrations using a three-bus system and the IEEE 30-bus system aim to exhibit the effectiveness of the proposed approach.     

防火墙技术与电力企业网络安全

为了解决电力企业在信息化建设中面临的网络信息安全问题，通过分析现今防火墙技术的分类及各种类型防火墙的优缺点，为电力企业在构建防火墙时对防火墙的选择与设置问题提出建议，并在此基础上以屏蔽子网防火墙为例介绍电力企业防火墙的主要构建方法。