电网故障计算中参数不对称的模拟方法研究

通过引入虚拟支路和虚拟节点,建立模拟参数不对称的虚拟端口,以虚拟端口为边界,将参数不对称电网分解成对称网络部分和模拟参数不对称的不对称网络部分.根据补偿法的基本原理,用从虚拟端口向对称网络的注入电流作为补偿电流,将参数不对称电网转化为对称电网.将不对称电网转化为对称电网后,可以利用基于对称分量法的各种故障计算方法进行电网故障计算.最后以一个不对称系统短路故障为例进行计算,结果证明算法有效.

Study on the Simulation Method of Parameter Unbalance in Power Grid Fault Calculation

By introducing the fictitious branch and fictitious node,the fictitious ports to simulate the parameter unbalance is established.By taking fictitious ports as boundary,the parameter unbalance power grid is separated into symmetrical network and unsymmetrical network to simulate parameter unbalance.Based on the compensation method theory,using the current injected into symmetrical network as compensation current,the parameter unbalance power grid changes to a balance power grid.After the parameter unbalance power grid changes to parameter balance power grid,the fault can be calculated by symmetrical component method.In the end,an unsymmetrical power grid with open circuit short to earth faults is analyzed as an example,and the result shows that the simulation method is effective.