×MW发电厂电气的一次设计.doc

2×300MW发电厂电气的一次设计 摘 要本次设计为2×300MW一次设计，内容包括：电气主接线方案的拟定、比较和选择；短路电流的计算；主要电气设备和导体的选择；设备汇总和绘制主接线图。短路计算按三相短路考虑，只220 kV母线上三相短路的情况，根据已知参数和计算结果进行主要电气设备和导体的选择，并开关设备校验，最后进行了主接线的绘制。 关键词：；；2×300MW An Electrical Power Plant Design Abstract: This design is for the 2 × 300MW generating unit, including the development, comparison and selection of plan of main electrical connection, selection of main electrical equipments and conductor, equipment list and main wiring map. According to installed capacity, number of advance wire and outgoing line of the power plant, double bus connection has been selected as main connection, in order to avoid cutting down of power production when either of the two buses meets breakdown or overhauling situations. On works load, high voltage power of 6 kV and low voltage of 380/220 V single bus connection are selected. Backup power is contained by the system itself so that power supplies on both first-class and second-class loads are continuous. Short circuit calculation is concerned in the worst situation of three phase short circuit, and only calculated three phase short circuit on 220 kV bus by method of operational curve. According to known parameters and result of calculation, main electrical equipments, includes main connection wires, main transformers, high-voltage circuit-breakers and disconnecting switches, and conductor were selected. In the same time, check of switchgears was also obtained. In the end, sum of equipments and drawing of main circuit wiring diagram were also finished. Key words: Two-bus; Power plant; Short circuit; Electrical equipment 正文： 1．前言 在电力系统中，大、中型电厂起着举足轻重的作用，一旦故障轻则引起大面积停电，重则可能引起电网崩溃。本次设计的电厂在电网占有重要位置，一旦发生事故将引起主网的解裂，所以对电厂主接线形式进行了详细的分析比较，以一种安全经济成熟的主接线形式。 现代电力工业在国际上已经迅速发展，其发展的特点是：采用大容量的发电机组，超高压输电线路和巨大的水、火、核电联合电力系统的形成，电力工业的迅速发展，对发电厂的设计提出了更高的要求，需要我们认真的研究对待。而现代化发电厂的设计是一门综合性的科学，它是在多种专业有机配合，密切协作下完成的一个统一整体，是在审议后的电力系统规划的基础上，为发电厂的发展制定具体方案，在设计中，贯彻国家各项政策，遵照有关的设计技术规定，从整体出发，深入论证电源布置的合理性，提出网络设计方案，并论证安全可靠性和经济性，为此需进行必要的计算，考虑近期与远期的关系，并