电力系统简单不对称故障的分析计算ppt课件

1、Xinjiang University电气工程及其自动化专业电气工程及其自动化专业电气工程学院 当网络元件只用电抗表示时，不对称短路的序网络方程当网络元件只用电抗表示时，不对称短路的序网络方程00022211100aaaaaaVZIVZIVZIE000222111aaaaaaVIjXVIjXVIjXE该方程组有三个方程，但有六个该方程组有三个方程，但有六个未知数，必需根据边境条件列出未知数，必需根据边境条件列出另外三个方程才干求解。另外三个方程才干求解。000cbaIIV00002210212021aaaaaaaaaIIaIaIIaIaVVV0210210aaaaaaIIIVVV0002221

2、11aaaaaaVIjXVIjXVIjXE)(0211XXXjEIa100122102111102)(aaaaaaaaaaIjXVIjXVIXXjIjXEVIII0210210aaaaaaIIIVVV 000222111aaaaaaVIjXVIjXVIjXE单相接地缺点的复合序网单相接地缺点的复合序网)(0211XXXjEIa100122102111102)(aaaaaaaaaaIjXVIjXVIXXjIjXEVIII1021)1(3aaaaafIIIIII 10020221100202123)2(23 3)2(23 aaaacaaaabIXjXXVVaVaVIXjXXVVaVaV 10012

3、2102111021102)()(aaaaaaaaaaIjXVIjXVIXXjIjXEVXXXjEIII1aI000222111aaaaaaVIjXVIjXVIjXEcbcbaVVIII00022102120221021202100aaaaaaaaaaaaaaaVVaVaVVaVaIIaIaIIaIaIII2121000aaaaaVVIII)(211XXjEIa 000122221012aaaaaaaaVIjXIjXVVIII2121000aaaaaVVIII000222111aaaaaaVIjXVIjXVIjXE两相短路的复合序网两相短路的复合序网)(211XXjEIa 0001222210

4、12aaaaaaaaVIjXIjXVVIII1112021233)(abcaaaaabIjIIIjIaaIIaIaI1)2(3acbfIIII)(211XXjEIa12222112aaaaaaIjXIjXVVIIaabcaaaaabaaaaaaVVVVVVVVaVaVIXjVVVVV212122110212121021)(211XXjEIa12222112aaaaaaIjXIjXVVII1aI000cbaIIV000cbaVVI0210210aaaaaaVVVIII000222111aaaaaaVIjXVIjXVIjXE)/(0211XXXjEIa102020211022010202aaaaa

5、aaaIXXXXjVVVIXXXIIXXXI0210210aaaaaaIIIVVV0210210aaaaaaVVVIII000222111aaaaaaVIjXVIjXVIjXE10202210202202211020221020220212)(2)2(33)(2)2(33aaaaacaaaaabIXXXXjX IXXXaXaIIaIaIIXXXXjX IXXaXXaIIaIaI120202)1 , 1()(13acbfIXXXXIII10202133aaaIXXXXjVV)/(0211XXXjEIa102020211022010202aaaaaaaaIXXXXjVVVIXXXIIXXXI1aI

6、正序分量的计算正序分量的计算)(0211XXXjEIa)(211XXjEIa)/(0211XXXjEIa)()(11naXXjEI短路电流的计算短路电流的计算1)1(3afII1)2(3acbfIIII120202)1 , 1()(13acbfIXXXXIII)(1)()(nannfImI短路类型短路类型f(n)f(n)三相短路三相短路f(3)f(3)0 01 1两相短路接地两相短路接地f(1,1)f(1,1)两相短路两相短路f(2)f(2)X2X2单相接地短路单相接地短路f(1)f(1)X2+ X0X2+ X03 3例例7-2 7-37-2 7-33)(nX)(nm0202XXXX20202

7、)(13XXXX 电力系统设计运转中，除需求知道缺点点的短路电力系统设计运转中，除需求知道缺点点的短路电流和电压外，有时还需求知道网络中某些支路电流和电压外，有时还需求知道网络中某些支路电流和节点电压。电流和节点电压。 根本思绪：先求出电流电压的各序分量在网络中根本思绪：先求出电流电压的各序分量在网络中的分布，然后将相应的各序分量进展合成求得各的分布，然后将相应的各序分量进展合成求得各相电流和相电压。相电流和相电压。1.Y1.YY Y1212衔接的变压器：不发生相位挪动。衔接的变压器：不发生相位挪动。0030223011jAajAaeVVeVV0030223011jAajAaeIIeII)()

8、()(212302230122121302301221222130230121000000AAjAjAaacAAjAjAaabAAjAjAaaaIaIajeIaeIaIaIaIIIjeIaeIaIaIaIIaIajeIeIIII1.1.电流分布计算电流分布计算常用电流分布系数法。常用电流分布系数法。2.2.电压分布的计算：电压分布的计算：000022221111IjXVVIjXVVIjXVVfhfhfh 非全相断线非全相断线 横向缺点和纵向缺点横向缺点和纵向缺点000222111)0(aaaaaaf fVIZ VIZ VIZV00cbaVVI0210210aaaaaaVVVIII0002221

9、11)0(aaaaaaf fVIjX VIjX VIjXV )/(1022010202021)0(1aaaaf faIXXXIIXXXIXXXjVI000222111)0(aaaaaaf fVIZ VIZ VIZV0210210aaaaaaVVVIII102022102022102022102022)(2)2(33)(2)2(33aacaabIXXXXjXIXXXaXaIIXXXXjXIXXaXXaI120202)(13acbIXXXXII10202133aaaIXXXXjVV00acbVII0021021aaaaaaVVVIII000222111)0(aaaaaaf fVIjX VIjX VIjXV)(021)0(021XXXjVIIIf faaa0021021aaaaaaVVVIII000222111)0(aaaaaaf fVIjX VIjX VIjXV13a