官亭变电站750 kV高压并联电抗器运行状况分析

官亭变电站750 kV 2#电抗器是国内目前运行电压等级最高的一组高压并联电抗器。分析了750 kV高压电抗器在官亭变电站的运行情况和技术监督数据:技术监督数据稳定,油色谱分析数据良好,继电保护和安全自动装置无动作,电抗器整体运行状况良好。提出了未来改造计划:重新建造3台电抗器的基础,将目前的条形基础改为方形基础,增强电抗器的底部支持面,放弃现在使用的千斤顶;制造一台新的电抗器,替换运行中的电抗器B相。     

官亭变电站750kV高压并联电抗器运行状况分析

官亭变电站750kV2＃电抗器是国内目前运行电压等级最高的一组高压并联电抗器。分析了750kV高压电抗器在官亭变电站的运行情况和技术监督数据：技术监督数据稳定，油色谱分析数据良好，继电保护和安全自动装置无动作，电抗器整体运行状况良好。提出了未来改造计划：重新建造3台电，抗器的基础，将目前的条形基础改为方形基础，增强电抗器的底部支持面，放弃现在使用的千斤顶；制造一台新的电抗器，替换运行中的电抗器B相。     

750kV输变电示范工程网损分析

对国家电网公司750kV输变电示范工程2006年1月至2007年6月期间损耗电量及损耗率进行了统计，分析了其构成及变化特征．指出在电量计量方面可能存在超标误差，导致750kV官亭变向兰州东变输送电量时出现零损，甚至负损；分析了750kV输电线路在运行初期输送功率较低的情况下，输送电量与线路损耗率之间的关系曲线，推算出使750kV输电线路损耗率最低的运行电流（功率）。     

750 kV输变电示范工程网损分析

对国家电网公司750 kV输变电示范工程2006年1月至2007年6月期间损耗电量及损耗率进行了统计,分析了其构成及变化特征,指出在电量计量方面可能存在超标误差,导致750 kV官亭变向兰州东变输送电量时出现零损,甚至负损;分析了750 kV输电线路在运行初期输送功率较低的情况下,输送电量与线路损耗率之间的关系曲线,推算出使750 kV输电线路损耗率最低的运行电流(功率)。     

世界海拔最高的750kV输变电工程成功投运

2008年11月30日,世界海拔最高的750kV输变电工程——官亭一西宁750kV输变电工程成功投运。官亭一西宁750kV输变电工程是国家电网公司和青海省重点建设项目之一,其中西宁750kV变电站是青藏联网工程的起点,海拔高度2630m,线路最高海拔2920m,是目前世界上同电压等级海拔最高的输变电工程。750kV主要电器设备外绝缘水平达到或超1000kV电压等级。官亭一西宁750kV输变电工程的建设和投入运行,对加快西北750kV主网架的建设步伐,     

某区域高压并联电抗器振动测试分析及优化

为厘清区域电网中高压并联电抗器的振动情况,合理优化电抗器振动测试工作,针对某省330 kV及以上的变电站,逐一开展了高压并联电抗器振动测试试验。通过试验测试、数据分析等手段总结了高压并联电抗器的振动特性,并根据最大振动值对所测电抗器进行等级划分,并针对性地提出振动测试建议。     

西北750kV示范工程输电线路OPGW光缆防振特性的研究

介绍了光纤复合架空地线（OPGW）光缆在国内第一个超高压西北750kV官亭-兰州东输电线路的应用。结合西北750kV输电线路的特点和对OPGW的要求，描述了750kV输电线路OPGW光缆的结构设计的特点，同时通过750kV官亭-兰州东输电线路大档OPGW光缆防振特性的研究，为西北750kV输电线路1235m大档距OPGW光缆推荐了满足技术条件的直线档防振方案，并提供了测试结果及分析意见，对探索和积750kV超高压等级上OPGW光缆的设计和运行经验具有现实意义。     

西北750 kV示范工程输电线路OPGW光缆防振特性的研究

介绍了光纤复合架空地线(OPGW)光缆在国内第一个超高压西北750 kV官亭-兰州东输电线路的应用。结合西北750 kV输电线路的特点和对OPGW的要求,描述了750 kV输电线路OPGW光缆的结构设计的特点,同时通过750 kV官亭-兰州东输电线路大档距OPGW光缆防振特性的研究,为西北750 kV输电线路1 235m大档距OPGW光缆推荐了满足技术条件的直线档防振方案,并提供了测试结果及分析意见,对探索和积累750 kV超高压等级上OPGW光缆的设计和运行经验具有现实意义。     

750kV示范工程系统调试综述

国家电网公司750kv示范工程系统调试范围为750kv官亭变电站变电工程、750kV兰州东变电站变电工程、750kV官亭变电站至750kV兰州东变电站一条140km的750kV线路。系统调试方案包括两部分：第一部分为750kV输变电示范工程系统调试方案．第二部分为750kV示范工程系统调试测试方案。本文详细叙述了系统调试方案中的试验项目和试验内容：并对系统调试测试项目进行了简单介绍。对系统调试结果进行了简单概括分析，并给出了系统调试结论。     

750 kV示范工程系统调试综述

国家电网公司750kV示范工程系统调试范围为750kV官亭变电站变电工程、750kV兰州东变电站变电工程、750kV官亭变电站至750kV兰州东变电站一条140km的750kV线路。系统调试方案包括两部分:第一部分为750kV输变电示范工程系统调试方案,第二部分为750kV示范工程系统调试测试方案。本文详细叙述了系统调试方案中的试验项目和试验内容;并对系统调试测试项目进行了简单介绍。对系统调试结果进行了简单概括分析,并给出了系统调试结论。     

Hydrogen release from a metal hydride tank with phase change material jacket and coiled-tube heat exchanger

Hydrogen fuel cells are received increasingly wide attention in order to develop green ships and reduce greenhouse gas emissions in the field of waterway transportation. Metal hydrides (MHs) can be used to store hydrogen for green ships due to their high volumetric storage capacity and safety. Various measures should be considered in the design and manufacture process of the MH reactor to strengthen its performance of heat and mass transfer and obtain an acceptable hydrogen storage capacity. In this work, LaNi₅ hydride is used as the hydrogen storage material and packed in the reactor. A basic axisymmetric numerical model for the hydrogen storage system without a heat exchanger has been developed and proved to be effective through the comparison between its simulation results and the published data during dehydriding. A hybrid heat exchanger, which is consisted of a phase change material (PCM) jacket and a coiled-tube, has been applied into the hydrogen storage system to relieve the thermal effect of MH in the dehydriding process on system performance. Effects of the heat transfer coefficient between the circulating heating water in the coil-tube and the MH bed, the temperature of circulating heating water and the pressure at the outlet on the dehydriding performance have been investigated. Based on parametric study, the relationships among the average dehydriding rate, the heat transfer coefficient, the heating water temperature and the outlet pressure have been found and fitted as simple equations. These fitted equations can be considered as a reference, which provides an important method to effectively control the dehydriding rate in order to satisfy the fuel requirement of the power unit and ensure the safe navigation of green ships in the future.     

聚苯乙烯反应器流体传热特性及换热系统结构改进的数值研究

聚苯乙烯反应过程中物料的升温速率及温度分布影响产品的质量和生产效率，反应器的设计与改造必须考虑物料搅拌过程中的升温速度和温度分布问题。在役聚苯乙烯反应器存在升温速率较慢，温度分布不合理等问题。利用ANSYS／FLORTAN程序计算了反应器内物料的温度场，找出了在役聚苯乙烯反应器存在的问题，提出了设备的改造方案。实践表明，第二种方案的装置内物料的升温速率较快，温度分布均匀，且降低了能耗。     

纵向振动圆管流场与阻力特性的数值模拟

在绝大多数换热设备中,流体绕流诱发的管束振动现象普遍存在,并在很大程度上决定强化换热的效果.由于对换热管束振动条件下的流场与换热特性缺乏深入的分析,影响了流体诱导振动强化传热技术的推广应用.利用CFD流场软件对换热管束强迫振动条件下的流场分布、换热特性及振动阻力状况进行了数值模拟研究,考察了管束振动频率在0.33～50 Hz范围内漩涡生成与脱落形态以及换热管束的局部场协同程度.数值模拟结果表明,管束较高频率的振动显著改善了流场的场协同度,提高了换热效率.     

Performance simulation and experimental confirmation of a mini-channel metal hydrides reactor

A theoretical and experimental study about a proposed mini-channel reactor was carried out to enhance heat transfer performance for metal hydrides applications, such as hydrogen storage, hydrogen compression and chemical heat pumps. The configuration of the reactor and working principles are described in detail. The predicted hydride bed temperature profiles in the reactor are compared with the experimental data from the performance test system, and a reasonable agreement is observed. The simulation of the hydrogen adsorption and desorption processes in a mini-channel reactor packed with LaNi₅ is conducted, and the influences of some important parameters, e.g. the bed thickness, the number of the mini-channels, hydrogen supply and discharge pressure are analyzed. Comparing with the traditional reactors, such as tubular reactor and disc reactor, the mini-channel reactor has some obvious advantages, therefore can be recommended for applications.     

±800 kV特高压直流工程干式平波电抗器关键技术分析

特高压直流是我国进行远距离、大规模电能传输的重要技术手段,平波电抗器为其中的一项重要设备。介绍了特高压直流输电系统平波电抗器绝缘控制、温升控制、噪音控制、防电晕控制措施及并联避雷器控制等关键技术,并对电抗器的运行维护工作提出了合理化建议。     

500 kV带高抗平行输电线路非全相谐振问题研究

从非全相状态下开断相谐振和邻线谐振的基本原理出发,分析了高抗中性点小电抗器限制谐振的数学模型,并计算了典型线路避开谐振的小电抗器数值解,通过理论推导和实际线路的仿真验证,分析了非全相谐振的影响因素,给出了抑制谐振的措施.     

Neutronics and thermal hydraulic coupling analysis of integrated pressurized water reactor

In this paper, three‐dimensional (3D) power distribution of newly designed small nuclear reactor core has been achieved by using neutron kinetic/thermal hydraulic (NK/TH) coupling. This is pressurized water reactor‐based small nuclear reactor in which plate type fuel element has been used and the core of the reactor has hexagonal type geometry. This paper depicts the design of the reactor core by using coupling approach of neutronics(Neutron Kinetic) and thermal hydraulic studies. For this purpose, neutronic analysis has been obtained by using lattice physics code, i.e. HELIOS and neutron kinetic code, i.e. REMARK. HELIOS code gives the cross‐section data which is being used as input to the REMARK code. At the same time, THEATRe code was used for the thermal hydraulic analysis of the reactor core. In the coupling process, some data (fuel temperature, moderator temperature, void fraction, etc.) from THEATRe code has been used in conjunction with HELIOS and REMARK codes. After finalizing the NK/TH coupling, 3D evaluation of the power distribution of the reactor core has been achieved and is included in the paper. The purpose of this paper is to evaluate the design and get the normal operational behavior of the reactor core by NK/TH coupling approach. Copyright © 2012 John Wiley & Sons, Ltd.     

Numerical simulations of HI decomposition in packed bed membrane reactors

Numerical simulations to develop an understanding of transport processes inside PBMRs (packed bed membrane reactors) and to evaluate effectiveness of PBMRs in increasing the conversion of HI (hydrogen iodide) decomposition reaction of IS (iodine–sulfur) thermochemical cycle are reported. The computational approach used in the simulations has been validated using the data reported for HI decomposition in a packed bed reactor (PBR). The validated computational approach has been used for parametric studies. Effects of different parameters (temperature, pressure, space velocity, membrane permeability, permselectivity, packed bed porosity and reactor diameter) on HI conversion are reported. The parameters having the maximum impact on the conversion are identified. The findings show that using a PBMR instead of a PBR leads to significant enhancement in conversion and the parameters having high impact on conversion are wall temperature, feed temperature, reactor diameter and packed bed porosity. Based on the findings of parametric studies, ranges of the parameters having maximum impact on conversion are suggested, e.g. the reactor wall temperature is recommended to be in the range of 690–700 K, the bed porosity is recommended to be in the range of 0.2–0.4.     

Chemical‐looping combustion — an overview and application of the recirculating fluidized bed reactor for improvement

This paper propose recirculating fluidized bed (RCFB) reactor for chemical‐looping combustion (CLC) to overcome some of the issues associated with the existing interconnected reactors arrangements like low residence time of bed material in the air reactor, high attrition of bed material in the cyclone separator, cluster formation in the air reactor, complex operation involving loop seals and high heat losses. RCFB has high solid circulation rate, long residence time, efficient fuel–oxygen carrier contact, low heat losses and low gas leak in between the reactors, as compared to the existing reactor configurations. A cold model study was performed on a Perspex made, semicircular, transparent RCFB reactor. A single RCFB reactor was operated in the alternate oxidation and fuel burning cycles to simulate the interconnected reactors arrangement for CLC. The generated experimental data has been used to predict the optimal RCFB reactor configuration for a RCFB‐based CLC power plant. Copyright © 2014 John Wiley & Sons, Ltd.