300MW汽轮发电机组厂用电设计论文

太原工业学院毕业设计

2×300MW汽轮发电机组厂用电设计

摘 要

本论文是对发电厂厂用电进行设计，主要运用发电厂电气部分，电力系统分析，电力系统继电保护等专业知识完成。具体设计内容包括厂用电接线设计，负荷分析计算，变压器选择，电动机自启动校验，继电保护设计，防雷设计等。在严格遵循发电厂电气部分的设计原则下，并结合实际情况确定了厂用电母线电压等级为6KV，利用换算系数法进行负荷分析计算，变压器选择低压分裂三绕组变压器，确定了合适的短路点进行短路电流计算，根据防雷保护要求确定避雷器，最后绘制了厂用电接线图。 关键词：发电厂，变压器，避雷器

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太原工业学院毕业设计

Design of Power Plant of 2×300MW Turbo Generator Factory

Abstract

The paper is designed towards the electricity power plant, using electrical power plants, power system analysis, power system protection and other expertise to complete. Specific design elements including electricity cable plant design, load analysis, the choice of transformers, motors start checking, relay protection design, lighting protection design and so on. The design follows strictly to the principles of the electrical power plants, combined with the actual situation, identifying the bus voltage electricity plant as 6 KV, using conversion factor method to calculate the load, choosing the low-voltage split three winding transformer, fixing the appropriate short-circuit point to calculate the short-circuit current,selecting the arrester according to the requirement of lighting protection, finally drawing the electric wiring diagram. Keyword: power plant, transformer, arrester

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太原工业学院毕业设计

目 录

前言................................................................1 第1章 厂用电电压等级确定及接线设计.................................2 1.1厂用电.......................................................2 1.2厂用电的电压等级确定.........................................2 1.3厂用电接线设计...............................................4 1.3.1对厂用电接线的要求......................................4 1.3.2厂用电接线的基本原则....................................4 1.3.3厂用电接线形式..........................................4 第2章 厂用电负荷计算及变压器的选择................................7 2.1厂用电负荷的分类.............................................7 2.2厂用电负荷的计算原则.......................................10 2.3厂用负荷的计算方法.........................................10 2.3.1换算系数法..................................................10 2.3.2电动机计算功率确定.....................................10 2.4厂用变压器的选择............................................14 2.4.1额定电压...............................................14 2.4.2厂用变压器的容量 ......................................14 第3章 厂用电动机的选择和自启动校验................................18 3.1厂用电动机的选择............................................18 3.2电动机自启动...............................................18 3.2.1电动机自启动分类.......................................18 3.2.2电动机自启动时厂用母线最低电压.........................19 3.2.3电动机自启动校验.......................................20 第4章 短路计算及电气设备选择....................................27 4.1短路概念及原因..............................................27 4.2短路后果....................................................27 4.3短路计算....................................................27 4.3.1短路计算基本假设.......................................27

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太原工业学院毕业设计

4.3.2短路计算的规定.........................................28 4.3.3短路电路计算的步骤.....................................28 4.4电气设备的选择和校验........................................29 4.4.1电气设备选择的要求和原则...............................29 4.4.2校验的原则及热稳定条件.................................30 4.4.3环境条件...............................................30 4.5电气设备的选择..............................................31 4.5.1断路器参数的选择.......................................31 4.5.2隔离开关参数的选择.....................................31 4.5.3电压互感器的选择.......................................32 第5章 继电保护总体方案和防雷保护.................................34 5.1主变压器保护规划............................................34 5.2变压器保护..................................................34 5.3母线保护....................................................35 5.4防雷保护设计................................................36 5.4.1雷电过电压的形式及危害性...............................36 5.4.2直击雷和感应雷保护.....................................36 5.4.3雷电波入侵保护.........................................36 5.4.4避雷器的选择...........................................37 结论..............................................................38 参考文献...........................................................39 致谢..............................................................40 附录..............................................................41

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