110KV变电站设计论文

110KV变电站电气部分设计

摘 要

本说明书以110kV地区变电站设计为例，论述了电力系统工程中变电站部分电气设计（一次部分）的全过程。通过对变电站的主接线设计，站用电接线设计，短路电流计算，电气设备动、热稳定校验，主要电气设备型号及参数的确定，运行方式分析，防雷及过电压保护装置的设计，电气总平面及配电装置断面设计和无功补偿方案设计，较为详细地完成了电力系统中变电站设计。

限于毕业设计的具体要求和设计时间的限制，本毕业设计只对变电站电气一次部分做了较为详细的理论设计，而对其电气二次部分并没有涉及，这有待于在今后的学习和工作中进行研究。

关键词：变电站 短路电流 动稳定 热稳定

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ABSTRACT

The statement about the 110kv transformer area substation design, discussed some electrical transformer substation design (one part) in power systems engineering of the entire process. Through the main transformer stations wiring design, stations wiring design stations, short circuit current calculations, check electrical equipment moving and thermal stability, set the main electrical equipment models and the parameters, the operating mode, design over-voltage protection and mine devices , design general electric graphic and distribution devices flood, and without power compensation. Completed substation design in power system，lastly.

Limited to the specific design requirements and design time of constraints, the design only is a part of the electrical transformer stations, and its second part did not involve, which research it in future study and work.

KEY WORDS: Substation, Short circuit currents , Moving stability，Thermal stability

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目 录

摘 要 ·································· I ABSTRACT ································ II 1绪 论 ································· 1

1.1选题背景和意义 ..................................................... 1

1.1.1选题背景 ·························· 1 1.1.2选题意义 ·························· 1 1.2原始资料 ........................................................... 1

1.2.1分析本变电站在电力系统中的作用 ··············· 1 1.2.2建设规模 ·························· 1 1.2.3环境情况 ·························· 1 1.2.4线路阻抗 ·························· 2 1.3所做工作 ........................................................... 2

1.3.1分析原始资料 ························ 2 1.3.2 拟定主接线方案 ······················· 2 1.3.3短路电流计算 ························ 2 1.3.4主要电器选择 ························ 2 1.3.5其他计算和设计 ······················· 3 1.3.6绘制电气主接线图 ······················ 3 本章小结 ............................................................... 3 2电气主接线设计 ····························· 4

2.1主变压器的选择 ..................................................... 4

2.1.1主变压器台数的确定 ····················· 4 2.1.2主变压器容量的确定 ····················· 4 2.1.3主变压器相数的确定 ····················· 5 2.1.4主变压器绕组数和接线组别的确定 ··············· 5 2.1.5主变压器调压方式的确定 ··················· 5 2.1.6主变压器冷却方式的确定 ··················· 6 2.1.7主变压器型号的确定 ····················· 6 2.2 主接线初步方案的拟订及技术比较 ..................................... 6

2.2.1 110kV电压侧接线 ······················ 6 2.2.2 10kV电压侧接线 ······················· 9 2.3方案经济比较 ...................................................... 10 2.4主接线最终方案的确定 .............................................. 12 2.5站用变接线设计 .................................................... 13

2.5.1选择变压器 ························· 13 2.5.2接线方案确定 ························ 13 本章小结 .............................................................. 13

III

3短路电流计算 ······························ 14

3.1短路故障产生的原因 ................................................ 14 3.2 短路故障的危害 .................................................... 14 3.3 短路电流计算的目的 ................................................ 15 3.4短路电流计算的内容 ................................................ 16

3.4.1短路点的选取 ························ 16 3.4.2短路时间的确定 ······················· 16 3.4.3短路电流的计算 ······················· 16 3.5短路电流计算方法 .................................................. 16

3.5.1标幺值法 ·························· 16 3.5.2 有名值法 ·························· 16 3.6三相短路电流周期分量起始值的计算 .................................. 16

3.6.1短路电流计算的基准值 ···················· 16 3.6.2网络模型 ·························· 17 3.6.3三相短路电流周期分量起始值的计算步骤 ············ 17 本章小结 .............................................................. 21 4主要电气设备的选择 ··························· 22

4.1断路器和隔离开关的选择 ............................................ 23

4.1.1 110kV断路器隔离开关的选择 ················· 24 4.1.2 10kV断路器隔离开关的选择 ·················· 26 4.2 电流互感器的选择 .................................................. 28

4.2.1 110kV侧电流互感器的选择 ·················· 29 4.2.2 10kV侧电流互感器的选择 ·················· 30 4.3 电压互感器的选择 .................................................. 31

4.3.1 110kV母线设备电压互感器的选择 ··············· 32 4.3.2 10kV母线设备电压互感器的选择 ················ 32 4.4高压熔断器的选择 .................................................. 33 4.5母线的选择与校验 .................................................. 33

4.5.1 110KV母线的选择 ······················ 34 4.5.2 10kV母线 ·························· 35 4.5.3主变110KV侧至110KV母线连线的选择 ············· 36 4.5.4主变10kV侧至10kV母线连线的选择 ·············· 37 4.6电缆选型及截面选择 ................................................ 37

4.6.1电缆芯线材质/芯数 ······················ 37 4.6.2电缆结构 ·························· 37 4.6.3电缆选择的具体技术条件简述 ················· 38 4.6.4穿墙套管的选择 ······················· 42 4.7绝缘子型号和绝缘子串 .............................................. 43 4.8高压开关柜的选择 .................................................. 44 本章小结 .............................................................. 44 5无功补偿、消弧线圈的计算与选择及防雷接地设计 ·············· 45

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