摘 要

近年来，随着各中小城市、乡镇、个体企业的迅速发展，用电负荷不断增加，完善供电网络，建设供电半径小、投资少的小型化变电所已势在必行。此类用电存在着负荷发展迅速，负荷分散，负荷变化大的特点。因而变电站应加快建设步伐，缩短建设周期，多布点、小型化。根据这一思想，设计一个35KV的小型化变电所。设计的目的是为了适应农村用电，满足农村经济发展的需要。

设计的依据是以三胡35KV变电所为背景资料，根据实地调查并预测未来几年的负荷变化，并通过对负荷资料的分析，安全，经济及可靠性方面考虑，确定了35kV，10kV的主接线，然后又通过负荷计算及供电范围确定了主变压器台数，容量及型号，根据最大持续工作电流及短路计算的计算结果，对高压断路器，隔离开关，母线，电压互感器，电流互感器进行了选型，而且对电气平面布置以及变电所的各种保护也作了详细的分析，提出了较为优化的设计和建设方案，从而完成了35kV电气一、二次部分的设计。

关键词： 变电所, 小型化, 设计

I

Abstract

In recent years, with the rapid development of all small and medium-sized cities , villages and towns , micro-business, power consuming load is increasing constantly, perfect the network of supplying power, it has already imperative to build the miniaturization transformer substation small in radius of electricity supplying, with little investment. This kind of has load to develop rapidly with electricity, load is scattered, load changes great characteristic. Therefore the transformer substation should quicken the steps of found, shorten construction period, miniaturization. According to this mind．Design the miniaturization transformer substation of one 35KV. The purpose to design is to use the electricity for adapting to the countryside and meet demands of rural economy development. Basis that design to take 35KV transformer substations of Sanhu as the materials , change according to field investigation and load that predict the following several years , And through an analysis of load materials, safe, the economy and dependability are considered, confirm 35 KV, to wire mainly 10 KV, calculate and supply power range not to confirm main voltage transformer platform count through load, capacity and type , the result of calculation of calculating that and short out according to the largest lasting job electric current, to the high-pressure circuit breaker, isolate the switch, the bus bar , voltage mutual inductor, the mutual inductor of electric current has carried on the selecting type, and fixed up to the electric level and various kinds of protection of the transformer substation have made of detailed analysis, have put forward the design that is comparatively optimized and built the scheme, thus finished the design of 35kV electric part one , two times.

Key words: The transformer substation, miniaturization, design

II

目录

摘 要 ............................................................... I ABSTRACT ............................................................ II 1 变电所所址选择 ..................................................... 1 1.1规划选所 .......................................................... 1 1.2 工程选所 .......................................................... 1 1.3变电所的所址选择一般要求 .......................................... 1 2 电气主接线设计 ................................................. 3 2.1电气主接线的概念及基本要求 ........................................ 3 2.2 主接线的设计原理 .................................................. 3 2.3 主接线的形式 ...................................................... 3 2.3.1 单母线接线 ...................................................... 4 2.3.2 双母线接线 ...................................................... 5 2.3.3 桥形接线 ........................................................ 6 2.3.4多角形接线 ...................................................... 7 3 短路计算 ........................................................... 9 3.1 短路的种类 ........................................................ 9 3.2 短路的原因及后果 .................................................. 9 3.2.1短路的原因： .................................................... 9 3.2.2 短路的后果： .................................................... 9 3.3 短路计算的目的 .................................................... 9 3.4变电所短路的计算 .................................................. 9 3.5 短路电流计算在继电保护的应用 ..................................... 10 4 主设备选型 ....................................................... 13 4.1 主变压器的选择 ................................................... 13 4.2 隔离开关的选择 ................................................... 13 4.3 高压断路器选择 ................................................... 13 4.4 电流互感器选择 ................................................... 14 4.5 电压互感器选择 ................................................... 14 4.6 母线的选择 ....................................................... 14 5 配电装置 ........................................................ 16 5.1 配电装置的安全净距 ............................................... 16 5．2 配电装置的形式 .................................................. 16 5.2.1屋外配电装置 ................................................... 16 5.2.2屋内配电装置 ................................................... 16 6 过电压与防雷设计 .................................................. 18 6.1 过电压的产生和分类 .............................................. 18 6.2 变电所的防雷设计原则 ............................................ 19

III