发电厂电气主接线设计作者:卢平摘要随着我国经济的不断发展,对电的需求也越来越大。电力工业是我国经济发展中最为重要的一种能源,主要是它可以方便、高效地转换其它能源形式。电力工业作为一种先进的生产力,是国民经济发展中最重要的基础能源产业。而火力发电是电力工业发展中的主力军。截止2006年底,火电发电量达到48405万千瓦,约占总容量的77.82%。由此可见,火力发电在我国这个发展中国家的国民经济中的重要性。本次设计是针对2*300MW火力发电厂电气部分的设计,电气主接线是发电厂、变电站电气设计的首要部分,也是构成电力系统的主要环节。所以本次设计电气部分主接线方案为一台半断路器接线。该设计主要从理论上在电气主接线设计、短路电流计算、电气设备的选择、配电装置的布局、防雷设计、发电机、变压器和母线的继电保护等方面做详尽的论述,同时,在保证设计可靠性的前提下,还要兼顾经济型和灵活性,通过计算论证火电厂实际设计的合理性与经济型。采用软件绘制电气图和查阅相关书籍,进一步完善了设计。关键词:电气主接线;短路电流;配电装置;电气设备选择AbstractAsChina'seconomicdevelopment,thedemandforelectricityisgrowing。ElectricpowerindustryinChina'seconomicdevelopmentisoneofthemostimportantenergy,mainlyitcanbeeasilyandefficientlyconvertotherformsofenergy。Asanadvancedproductivityintheelectricalindustry,isthemostimportantfoundationinthedevelopmentofenergyindustryofthenationaleconomy。Thermalpoweristhemainforceinthedevelopmentoftheelectricpowerindustry。Bytheendof2006,thermalpowergeneratingcapacityreached484.05million-kilowatt,77.82%percentoftotalcapacity。Thus,thermalpowergenerationinChina,theimportanceofdevelopingthenationaleconomy。Thisdesignisdesignedforelectricalpartsofthe2*300MWthermalpowerplant,mainelectricalconnectionistheprimarypartoftheelectricdesignofpowerplantandsubstation,constitutethemainpartofpowersystem。Designofmainelectricalconnectionschemeforoneandahalfcircuitbreakerconnection。Thedesigntheoryinthedesignofmainelectricalwiring,electricalequipmentforshort-circuitcurrentcalculations,selectionanddistributionequipmentforlightningprotectiondesign,layouts,generators,transformersandrelayprotectionofBusbarinelaborateonthese,atthesametime,ensurethereliabilitydesignofpremise,alsoconsidereconomicandflexibilitythroughcalculationsjustifytheactualdesignofthermalpowerplantandcheap。Drawelectricaldiagramssoftwareandcheckoutbooks,furtherimprovedthedesign。Keywords:mainelectricalwiring;shortcircuitcurrent;distributionequipment;electricalequipmentselection目录1原始资料介绍...........................................................................................................11.1原始资料分析.............................................................................................11.2本次设计主要内容.....................................................................................12电气主接线设计方案确定.......................................................................................22.1电气主接线设计原则与要求.....................................................................22.1.1电气主接线设计原则..........................................................................22.1.2电气主接线设计基本要求..................................................................22.1.3大机组超高压主接线的特殊要求......................................................42.2500KV电气主接线的确定.........................................................................52.3主接线方案的确定.....................................................................................72.4主变压器的选择.........................................................................................92.4.1发电厂主变压器的容量和台数的确定..............................................92.4.2主变压器型式的选择..........................................................................92.4.3绕组容量和连接方式的选择..............................................................92.4.4电气设备的选择..................................................................................93厂用电设计.............................................................................................................113.1厂用负荷分类...........................................................................................113.2厂用电接线基本要求...............................................................................113.3厂用电的电压等级...................................................................................123.4厂用电系统中性点接地方式...................................................................123.5厂用电源及其引接...................................................................................133.6备用电源数量...........................................................................................153.7厂用变压器的选择...................................................................................153.7.1火电厂主要厂用电负荷....................................................................163.7.2厂用电负荷的计算方法....................................................................183.7.3厂用变压器的选择............................................................................203.7.4厂备用变压器选择............................................................................213.8厂用电接线的确定...................................................................................244短路电流计算.........................................................................................................254.1短路电流计算的目的...............................................................................254.2短路电流计算的一般规定.......................................................................254.3短路电流计算步骤...................................................................................264.4电路元件参数计算...................................................................................274.5各点短路电流计算................