有机朗肯循环技术在低品位余热发电系统中的应用

介绍了有机朗肯循环(ORC)技术的原理和特征,阐述回收低品位余热进行发电的ORC技术在国内外的发展现状与趋势,并以有色金属工业中电解铝工艺环节余热回收为例说明ORC发电系统主要部件的设计选型思路。     

Proposal and characteristics evaluation of a CO2-recovering hybrid power generation system utilizing solar thermal energy

A CO₂-recovering hybrid power generation system utilizing solar thermal energy is proposed. In the system, relatively low temperature saturated steam around 220°C is produced by using solar thermal energy and is utilized as the working fluid of a gas turbine in which generated CO₂ is recovered based on the oxygen combustion method. Hence, solar thermal utilization efficiency is considerably higher as compared with that of conventional solar thermal power plants in which superheated steam near 400°C must be produced for use as the working fluid of steam turbines; the requirement for solar radiation in the location in which the system is constructed can be significantly relaxed. The proposed system is a hybrid energy system using both the fossil fuel and solar thermal energy, thus the capacity factor of the system becomes very high. The fuel can be used exergetically in the system; i.e., it can be utilized for raising the temperature of the steam heated by utilizing the turbine exhaust gas more than 1000°C. The generated CO₂ can be recovered by using an oxygen combustion method, so that a high CO₂ capturing ratio of near 100 percent as well as no thermal NO_x emission characteristics can be attained. It has been shown through simulation study that the proposed system has a net power generation efficiency of 63.4 percent, which is higher than 45.7 percent as compared with that of the conventional power plant with 43.5 percent efficiency, when the amount of utilized solar energy is neglected and the temperature of the saturated steam is 220°C.     

风-光-水多能互补发电系统(火用)分析模型

将?的概念引入风、光、水等多种异质能源资源的同质化表征,采用?分析方法建立有效的风力发电、光伏发电和水力发电系统的?分析模型。基于?分析模型,计算各发电系统的输入?值和输出?值,同时,建立风-光-水多能互补发电系统(MEGPS)总?效率、可持续性指数和单位?损失比等能效分析指标,对风-光-水MEGPS进行能效分析。通过算例分析,验证了所提?分析模型的正确性和能效指标的适用性。所提出的方法为提高MEGPS利用效率提供了科学依据。     

汽车尾气的余热发电及有效利用

基于热电偶温差发电原理,对汽车尾气废热进行回收,将排气中所含低品位能源转换为电能;为了使电能充分利用,结合热电制冷原理,设计一车载冰箱,将冷端置于车载冰箱中,实现汽车冰箱冷冻冷藏的功能。通过对废热回收、温差发电、半导体制冷及冰箱结构进行设计和计算,完成了新型车载冰箱的设计工作。该设计具有结构简单、坚固耐用、无运动部件、无噪声、使用寿命长等优点,同时还可降低尾气废气温度,减少温室效应,节省能耗,提高汽车经济性。     

发电行业的节能与节电

电力行业由于自身特点,总体能效的提高涉及生产、供应和使用各个方面。发电侧在完成能源转换的同时,也是自身消耗能源较大的行业,需求侧管理的开展对发电侧能效的提高也有积极的影响。简要介绍了我国发电行业节能节电的成绩,提出了主要目标和技术政策建议。     

An experimental study of the characteristics of a Darrieus turbine for tidal power generation

The Darrieus turbine was initially developed for wind turbines. An example of its application to water turbines is found in the Darrieus turbine installed in a duct for low head power generation, but no example is known of its application in a natural water channel. The authors have developed a Darrieus turbine that is suitable for tidal current power generation with the aim of establishing tidal current power generation technology through demonstrations in test channels and oceans. The efficiency of tidal current power generation is influenced by the characteristics of the turbine. The characteristics of the Darrieus turbine are mainly affected by the solidity and the number of blades. The Darrieus turbine was tested in test channels to find the most suitable values for the rotor solidity and the number of blades. This paper describes and examines those test results. © 2000 Scripta Technica, Electr Eng Jpn, 132(3): 38–47, 2000     

溴化锂吸收式热泵机组在电厂余热回收中的应用

针对传统的热电厂供热系统热能利用率低的问题,在供热系统中首次采用溴化锂吸收式热泵机组的热电联产技术,结果表明：热泵技术在热电厂中的应用,提高了机组热效率,节约了燃煤量,使电厂能源综合利用水平得以提升;减少了CO2和SO2排放,改善了环境,提高了电厂环保水平。     

基于滑模变结构控制的余热发电机机组励磁控制研究

水泥生产过程中会产生大量中低温余热,利用余热发电是水泥生产企业节能的重要手段。为维持余热发电系统的电能稳定,以单机无穷大电力系统为例,建立余热发电机组励磁系统数学模型,设计基于指数型终端滑模变结构控制理论的同步发电机励磁控制器。针对电力系统中三相短路和三相断路故障利用Matlab进行时域仿真,与采用快速终端滑模变结构控制的仿真结果进行对比分析,仿真结果表明该指数型终端滑模变结构励磁控制系统具有更好的适应性及稳定性。     

节能发电调度计划生成系统的研究开发及应用

对节能发电调度工作背景进行详细描述,进一步介绍了贵州节能发电调度工作一年来的技术成果,着重介绍了计划生成系统的结构,功能,特点,算法及应用等,进而介绍了贵州实施节能发电工作的效益进行分析。对节能发电调度工作面临的难题进行了介绍,以及贵州节能发电调度的工作重点。     

余压发电贯流式水轮机飞逸特性研究北大核心CSCD

随着贯流式水轮机发电技术的日益成熟,利用其回收循环水系统余压能的工业应用越来越多。本文将一维特征线(MOC)方法与三维计算流体力学(CFD)方法相结合,开发了一维管网和三维贯流式水轮机耦合模拟方法,模拟了真实系统中贯流式水轮机飞逸过程,探究了该过程中故障水轮机流动特性及转轮受力特性。主要结果表明:由稳态工况到飞逸状态所需的时间随着转动惯量减小而变短;转轮和尾水管域的监测点压力脉动振幅高值均发生在转轮叶频及其高次谐波;飞逸过程中,转轮所受轴向力大幅下降,而径向力表现出大幅增加且剧烈振荡特性;转轮叶片表面压力出现明显的交变规律,负压区位于进水侧叶缘处;尾水管内逐渐形成较大旋涡,并沿着流动方向逐渐向管道壁面发展。     

Characteristics and economic evaluation of a CO2‐capturing solar thermal hybrid power generation system with heat storage

For wide use of a power plant utilizing solar energy, improvement of its economics is important. Both the economics and characteristics of a CO₂‐capturing solar thermal hybrid power generation system are evaluated in this paper. Since a relatively low temperature steam of 220 °C is produced by using solar thermal energy and is utilized as the working fluid of a gas turbine, the solar collector can attain high heat collecting efficiency. The net fuel‐to‐electricity conversion efficiency of the hybrid system is estimated to be higher than 60% on the lower‐heating‐value‐ basis. It has been estimated that the gross income and the period of depreciation of the proposed system are 34.8 × 10⁵ yen/year and 8.89 years, respectively, and that the system is economically feasible, under the assumptions of a solar collector area of 10 ha, a maximum net power output of 4 MW, and a heat storage capacity of 2000 m³. The amount of fuel saving and reduction of CO₂ emission of our system, compared to a conventional natural gas firing plant, are also estimated in the paper. © 1999 Scripta Technica, Electr Eng Jpn, 126(4): 21–29, 1999     

风力发电无功补偿技术及发展趋势

阐述风力发电及其无功补偿的重要意义，探讨常见的风力发电无功补偿的方法，展望风力发电无功补偿技术的发展趋势，提出合理投切并联电容器的补偿方式。     

Proposal and evaluation of a gas engine and gas turbine hybrid cogeneration system in which cascaded heat is highly utilized

A high‐efficiency cogeneration system (CGS) is proposed for utilizing high‐temperature exhaust gas (HTEG) from a gas engine (GE). In the proposed system, for making use of heat energy of HTEG, H₂O turbine (HTb) is incorporated and steam produced by utilizing HTEG is used as working fluid of HTb. HTb exhaust gas is also utilized for increasing power output and for satisfying heat demand in the proposed system. Both of the thermodynamic characteristics of the proposed system and a gas engine CGS (GE‐CGS) constructed by using the original GE are estimated. Energy saving characteristics and CO₂ reduction effects of the proposed CGS and the GE‐CGS are also investigated. It was estimated that the net generated power of the proposed CGS has been increased 25.5% and net power generation efficiency 6.7%, compared with the original GE‐CGS. It was also shown that the proposed CGS could save 27.0% of energy consumption and reduce 1137 t‐CO₂/y, 1.41 times larger than those of GE‐CGS, when a case study was set and investigated. Improvements of performance by increasing turbine inlet temperature were also investigated. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 37– 45, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20708     

Compensation of power fluctuations of wind power generation by means of biomass gas turbine generator and flywheel energy storage equipment

Power generation using natural energy contains electric power fluctuations. Therefore, in order to put such power generation systems to practical use, compensation for system power fluctuations is needed. In this paper, we propose a power compensation method using a biomass gas turbine generator and flywheel energy storage equipment. The gas turbine generator is used for compensation of low‐frequency power fluctuations in order to decrease the required flywheel capacity. The usefulness of the proposed system is confirmed by experiments using a test plant. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(3): 1–8, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20896     

半导体温差发电技术应用及研究综述

半导体温差发电直接将热能转换为电能,具有无污染、结构紧凑、无旋转部件、无噪声、免维护等优点,是一种新型的节能环保发电技术,可将地热能、太阳能、工业及生活余热废热、汽车尾气废热等低品位热能转化为电能,提高能源利用率。介绍了半导体温差发电的原理、应用领域及研究状况,总结了半导体温差发电技术存在的问题,分析了提高半导体温差发电效率的关键技术及未来的研究方向。     

基于风光联合发电控制系统的研究与实现

随着科技的进步,分布式能源的利用已经逐渐成为能源产业的发展方向。通过综合分析风能与太阳能的不同特点,提出了基于风光联合发电的控制系统。以充电控制器作为主控制芯片对系统进行综合控制管理。提出了基于微电流的电压检测法来检测电压对本系统的影响。     

适用于电力系统稳定计算的水轮机调速系统模型研究

为满足电力系统稳定性仿真计算的需要,需建立符合并网运行水电机组实际的水轮机调速系统模型,通过水轮机调速系统理论建模研究,并以试验修正理论模型,建立了符合并网运行机组实际的适用于电力系统稳定分析计算用的水轮机调速系统模型。     

垂直轴永磁同步风力发电系统建模及瞬时功率控制策略

以垂直轴风轮(VAWT)和永磁体励磁多极直驱式同步风力发电机组(D-PMSG)为对象,建立了包括风力机模型、传动系统模型和发电机模型的垂直轴永磁同步风力发电系统的数学模型及结构,提出对有功功率、无功功率进行瞬时控制策略:通过频率控制环和电压控制环对负载或并网瞬时有功功率和无功功率进行分解计算,得到逆变器输出电流参考值,与实际的逆变器输出电流测量值比较后产生控制波,再与定频三角载波信号比较,产生PWM控制信号控制逆变器的各桥臂导通和关断.运用Matlab/Simulink建立了系统仿真模型,对有功功率、无功功率瞬时控制策略进行仿真,结果验证了该模型的合理性及控制策略的正确性和可行性.     

钢铁企业余热余能转换或替代电能的途径

钢铁企业是用能大户,利用余热余能技术发电或替代耗电设备可有效降低电能消耗,减少企业外购电能。余热余能转换成电能的主要途径有可燃废气通过燃烧发电,燃气—蒸汽联合循环发电,烧结余热发电,转炉轧钢加热炉发电等。替代电能的主要途径有汽轮机拖动风机旋转等。这些措施为钢铁企业实现节能降耗提供了有效途径。     

基于新型直流风电机组的串联型全直流发电系统设计研究

通过直流风电机组(DC wind turbine, DCWT)建设直流风电场实现风能的直流汇集与直流传输是海上风电系统的主要发展方向之一。为了使DCWT具备高压绝缘隔离、能量双向流动以及直流短路故障自清除能力,提出了一种适用于串联型全直流发电系统的新型DCWT拓扑。该DCWT拓扑采用了H桥结构的DC/DC变换器代替传统的隔离型DC/DC变换器,将DCWT直接串联并加以调制实现低压直流到高压直流的变换。基于PSCAD/EMTDC搭建了基于新型DCWT的串联型全直流发电系统仿真模型。经风电系统的DCWT在输出功率均衡、输出功率不均衡、高压直流母线电压波动等稳态运行工况以及故障DCWT动态切入切出等故障运行工况下的仿真,验证了该DCWT的输出特性、系统的运行特性以及系统对故障DCWT的处理能力,提高了直流风电场的运行可靠性与灵活性,为直流风电场的建设提供了一种切实可行的解决方案。