虎石台220 60KV降压变电所电气部分初步设计计算书.doc
《虎石台220 60KV降压变电所电气部分初步设计计算书.doc》由会员分享,可在线阅读,更多相关《虎石台220 60KV降压变电所电气部分初步设计计算书.doc(15页珍藏版)》请在三一办公上搜索。
1、第一章 短路电流的计算1.1系统计算电路图和等值电路图取SB = 100MVA,VB = Up,求得等值电路图中各阻抗标幺值如下:发电机1:X2 = X4 = Ud%/100SB/S = 12.4/100100/200/0.85 = 0.0527变压器1:X3 = X5 = Xd%/100SB/S = 14/100100/240 = 0.0583 发电机2:X6 = X8 =X10= Ud%/100SB/S = 18/100100/125/0.85 = 0.1224变压器:X7 = X9 = X11 = Xd%/100SB/S = 10.5/100100/160 = 0.0656线路:2100
2、KM: X= 1/21000.4100/2202 = 0.041360KM: X”= 600.4100/2202 = 0.0496X1 = X + X = 0.0413 + 0.0496 = 0.090948KM线路: X12 = 480.4100/2202 = 0.0397260KM线路: X13 = 1/2600.4100/2202 = 0.02482100KM线路: X14 = 1600.4100/2202 = 0.041380KM线路: X15 = 800.4100/2202 = 0.06611.2 220KV母线上K1点发生短路时的短路计算首先进行网络化简,化简后的网络图见图:X1
3、= X* + X1 = 0.05 + 0.0909 = 0.1409X2 =(X2 + X3)/2 =(0.0527 + 0.0583)= 0.0555X3 = (X6 + X7)/3 =(0.1224 + 0.0656)/3 = 0.0627 X4 = X12 = 0.0397 X5 = X13 = 0.0248 X6 = X15 = 0.0661 X7 = X14 = 0.0413进一步化简如下:对X5 X6 X7 进行三角变换网络见图1-4所示X”1 = X5X7/(X5 + X6 + X7)= 0.02480.0413/(0.0248 + 0.0661 + 0.0413) = 0.00
4、748X”2 = X6X7/(X5 + X6 + X7)= 0.06610.0413/(0.0248 + 0.0661 + 0.0413) = 0.02066X”3 = X5X6/(X5 + X6 + X7)= 0.02480.0661/(0.0248 + 0.0661 + 0.0413) = 0.01240网络见图1-5所示X = X1X2/X1 +X2 = 0.14090.0555/(0.1409 + 0.0555)= 0.03983X“ = (X + X3)X4/(X + X3 + X4)=(0.03983 + 0.04742)0.07507/(0.03983 + 0.04742 + 0
5、.07507)= 0.04035X# = X + X” = 0.02066 + 0.04035 = 0.06101C3 = X”/(X + X3) = 0.04035/(0.03983 + 0.04742)= 0.46250C4 = 1 - C3 = 1 - 0.4625 = 0.5375C1 = C3 X/X1 = 0.46250.02066/0.14091 = 0.13072C2 = C3 - C1 = 0.4625 - 0.13072 = 0.33178X = 0.06101X1 = X/C1 = 0.06101/0.13072 = 0.46674X2 = X/C2 = 0.06101/
6、0.33178 = 0.18389X4 = X/C4 = 0.06101/0.5375 = 0.11351Xjs1 = X1SG1/SB = 0.4667411000/100 = 51.3409Xjs2 = X2SG2/SB = 0.18389200/0.85/100 = 0.43268Xjs4 = X4SG3/SB = 0.11351125/0.85/100 = 0.16692X = X + 1/2(Ud%/100)(100/S变)= 0.06101 +(1/2)(14.3/100)(100/120000)= 0.06107X1 = X/C1 = 0.06107/0.13072 = 0.46
7、719X2 = X/C2 = 0.06107/0.33178 = 0.18407X4 = X/C4 = 0.06107/0.5375 = 0.11362Xjs1 = X1SG1/SB = 0.4671911000/100 = 51.39103Xjs2 = X2SG2/SB = 0.18407200/0.85/100 = 0.43310Xjs4 = X4SG3/SB = 0.11362125/0.85/100 = 0.16709d1点短路有名值:I” (3) = 1/Xjs1SG1/Uav = 1/51.3408911000/230 = 0.5378250s:I”d1(3) = I”+ 2.41
8、1SG2/Uav + 6.763SG3/Uav= 0.537825 + (2.4112002 + 6.7631253)/0.85/(230)= 10.775900.6s:I”d1(3) = I”+ 1.872SG2/Uav + 3.359SG3/Uav= 0.537825 + (1.8722002 + 3.3591253)/0.85/(230)= 6.969101.2s:I”d1(3) = I”+ 1.925SG2/Uav + 2.7945SG3/ = 0.537825 + (1.9252002 + 2.79451253)/0.85/(230)= 5.906554s:I”d1(3) = I”+
9、 2.119SG2/Uav + 2.49SG3/Uav= 0.537825 + (2.1192002 + 2.491253)/0.85/(230)= 5.79850d2点短路有名值:I” (3) = 1/Xjs1SG1/Uav = 1/51.3910311000/63 = 1.961570s:I”d2(3) = I”+ 2.411SG2/Uav + 6.02SG3/Uav= 1.96157 + (2.4112002 + 6.021253)/0.85/(63)= 36.698540.6s:I”d2(3) = I”+ 1.872SG2/Uav + 3.186SG3/Uav= 1.96157 + (
10、1.8722002 + 3.1861253)/0.85/(63)= 22.915991.2s:I”d2(3) = I”+ 1.925SG2/Uav + 2.827SG3/Uav= 1.96157 + (1.9252002+2.8271253)/0.85/(63)= 21.693104s:I”d2(3) = I”+ 2.119SG2/Uav + 2.476SG3/Uav= 1.96157 + (2.1192002 + 2.4761253)/0.85/(63)= 21.11063冲击电流:d1点:Ich1 = 2.55I”0s = 2.5510.77599 = 27.4785d2点:Ich2 =
11、2.55I”0s = 2.5536.69854 = 93.5813d1(3)点处短路容量:S”1 = 23010.77599 = 4292.8345d2(3)点处短路容量:S”1 = 23010.77599 = 4292.8345名称 短路点基准容量(MVA)基准电压(KV)等值电抗短路电流有名值冲击电流(KA)短路容量(KW)d1(3)1002200.0610110.775927.47854292.8134d2(3)100630.0617036.698593.58134004.5110第二章 电气设备的选择2.1母线选择2.1.1 220KV侧母线选择 (1)根据最大长期工作电流选择Igma
12、x = 1.05 = 1.0594.5/(230) = 316.3(A)故选择LGJ400型钢芯铝纹线,Ie = 825(A) (2)热稳定校验查当实际环境温度为38时的温度修正系数为K = 0.85,故有F = 0 + (e - 0)( Igmax/Ie)2 = 38 + (70 - 38)260/(0.85825) 2 = 44.5查表得C值为C = 97.5根据公式:S Smin = I/C由以上短路计算得I = 5.7985(KA),Iz”= 10.78(KA).”= Iz”/ I = 10.78/5.7985 = 1.86td = tb + tgf = 3 + 0.05 = 3.05
13、s查曲线得tz = 3.2stfz = 0.05”2 = 0.051.862 = 0.17stdz = tz + tfz = 3.2 + 0.17 = 3.37s取Kf = 1,S Smin = I/C = 5798.553.371/2/97.5 = 109.176 mm2300mm2故所选母线合格。2.1.2 63KV侧母线选择(1)根据最大长期工作电流选择Igmax1 = 0.71.05 = 0.71.05120/(63) = 59.4(A)Igmax2 = 1.05 = 1.05120/(63) = 1154.7(A)故选择1008mm2的矩形铝母线,当母线为立放,正常最高发热温度为70
14、0C时的,额定电流Ie = 1609(A). (2)热稳定校验查当实际环境温度为38时的温度修正系数为K = 0.85,故有F =0 + (e -0)( Igmax/Ie)2 = 38 + (70 - 38)1214.134/(0.851609) 2 = 63.2查表得C值为C = 89.5根据公式:S Smin = I/C由以上短路计算得I = 21.1106(KA),Iz”= 36.6985(KA). ”= Iz”/ I = 36.6985/21.1106 = 1.74td = tb + tgf = 3 + 0.05 = 3.05s查曲线得tz = 3.15stfz = 0.05”2 =
15、0.051.742 = 0.15stdz = tz + tfz = 3.15 + 0.15 = 3.3s取Kf = 1,S Smin = I/C = 211103.31/2/89.5 = 428.56 mm2800mm2故所选母线合格。(3)动稳定校验:跨距取1.2m两回路相间距离0.75mf = 1.73ish210-7/a = 1.73211102111010-7/0.75 = 220.27(N/m)M = f L2/10 = 220.271.22/10 = 31.72(N/m)W = b2h/6 = 0.0080.0080.1/6 = 1.06710-5(m3) = M/W = 31.7
16、2/(1.06710-5) = 29.73106(Pa)查手册得硬铝导线母线的最大允许应力a = 70106(Pa)a 所以动稳定满足要求。2.2 高压断路器的选择:2.2.1 220KV侧断路器的选择(1)根据最大长期工作电流选择Igmax = 1.05S/Ue 1.05120000/230= 1.05120000/(230) = 316.2875(A)本设计选用SW7-220型断路器,有关技术数据见表2-1表2-1 LW11-220(P)型断路器有关技术数据表安装地点型号额定电压(KV)最高工作电压(KV)额定电流(A)额定开断电流(KA)额定关合电流(KA)热稳定电流(kA)220KV侧
17、SW7-2202202521600205521(4s)(2)热稳定校验热稳定校验公式:Ir2tr I2tdz 在验算电器的短路热效应时,应采用后备保护的动作时间,通常取3s。由以上短路计算得I = 5.7985(KA),Iz”= 10.7759(KA)。”= Iz”/ I = 10.7759/5.7985 = 1.8584td = tb + tgf = 3 + 0.05 = 3.05s查曲线得tzj = 3.3stfz = 0.05”2 = 0.051.85842 = 0.17268stdz = tz + tfz = 3.3 + 0.17268 = 3.47268s短路发热量为:QK = I2
18、tdz = 5.798523.47268 = 116.76054(KA2S)(3)动稳定校验Idw Icj;55 2.5510.7759(4)按额定开断电流选择Iekd Izt; 55 10.7759(5)按额定关合电流选择Ieg icj;55 10.7759其保证值与计算值的比较见表22。表22 220KV断路器各项技术数据与各项计算数据比较表计 算 数 据LW11-220P断路器保证值电网电压Uew = 220KV额定电压Ue = 220KV长期最大工作电流Igmax = 316.288A额定电流Ie = 1600A次暂态短路电流I(3) = 10.7759KA额定开断电流Iekd = 2
19、0KA短路冲击电流ich = 27.4785KA额定关合电流iegd = 55KA短路冲击电流ich = 27.4785KA动稳定电流idw = 55KA热效应Qd = 116.76KA2.S热稳定:Qz = 1764KA2.S2.2.2 63KV侧断路器的选择(1)根据最大长期工作电流选择流过主变低压侧的电流:Igmax = 1.05Se/Uav = 1.05120000/63 = 1154.7A流过最大负荷出线的电流Igmax = 1.05Se/Uav= 1.0535000/(0.8563) = 336.7877A本设计选用LW(OFPI)-63型断路器,有关技术数据见表2-3。表2-3
20、LW(OFPI)-63型断路器有关技术数据表安装地点型 号额定电压(KV)最高工作电压(KV)额定电流(A)额定开断电流(KA)额定关合电流(KA)额定短时耐受电流(KA)63KV侧LW(OFPI)-636372.520004010031.5(4S)其他校验方法同220KV侧断路器的校验。其保证值与计算值的比较见表24。表24 35KV断路器各项技术数据与各项计算数据比较表计 算 数 据LW(OFPI)-63断路器保证值电网电压Uew = 63KV额定电压Ue = 63KV长期最大工作电流Igmax = 1154.7A额定电流Ie = 2000A次暂态短路电流I= 36.6985KA额定开断电
21、流Iekd = 40KA短路冲击电流ich = 93.5813KA额定关合电流iegd = 100KA短路冲击电流ich = 93.5813KA动稳定电流idw = 100KA热效应:QK = 1471.1605KA2S热效应:QK = 3669KA2S2.3 隔离开关的选择及校验2.3.1 220KV侧隔离开关选择与校验(1)根据最大长期工作电流选择Igmax = 1.05Se/Uav = 1.051200/230 = 316.2875(A)本设计母线隔离开关选用GW6220GD单柱剪刀型,出线隔离开关选用 GW12220D型 ,有关技术数据见表2-7表2-7 220KV隔离开关有关技术数据
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 虎石台220 60KV降压变电所电气部分初步设计计算书 石台 220 60 KV 降压 变电所 电气 部分 初步设计 计算
链接地址:https://www.31ppt.com/p-3992182.html