清远水电站电气一次设计

第二节、6.3KV侧短路电流计算

6.3KV母线短路即d2点短路,得等效电路图如下:

X15?11?X4??1.718?0.859 2211X16??X7?X3??1.718?0.42?12.7

22Y→△转换有:

X18?X16?X2?X16?X21.279?0.42?1.279?0.42??28.558 X10.02X1?X20.02?0.42X19?X1?X2??0.02?0.42??0.447

X161.279

最终等值电路如图所示.各组电源支炉的计算入下。

系统支路:

I\?Izt?1100??20.50KA 0.4476.3?3电站G3G4支路:

I\?Izt?1100??0.32KA 28.5586.3?3电站G1G2支路:

X15js?X*j?Se35?0.859??0.30 Sj100查运算曲线得: 有名值计算:I\?I*?SeUj3?356.3?3?I*?3.21?I*p

T Ip* I\S1 0 3.727 11.95 0.2 2.950 9.47 1 2.952 9.48 4 2.993 9.61 ich?1.9?I\?2?1.9?(11.95?0.32?20.50)?2?87.8KA

第三节、10KV侧短路电流计算

10V母线短路即d3点短路,得等效电路图如下：

X15?11?X4??1.718?0.859 2211X16??X7?X3??1.718?0.42?12.7

22

Y→△转换有:

X18?X16?X2?X16?X21.279?0.42?1.279?0.42??28.558 X10.02X1?X20.02?0.42X19?X1?X2??0.02?0.42??0.447

X161.279对X15、X18、X19、X12支路进行星网变换，Zms?ZmZs?Y求得各电源点对d3点的转移电抗有：

?Y?111111??????3.436 X15X18X190.85928.5580.447Xg1.2?X15?X12??Y?0.859?3?3.436?8.855 Xg3.4?X18?X12??Y?28.558?3?3.436?294.376 X??X19?X12??Y?0.447?3?3.436?4.61