城市配电网电容电流补偿研究

Compensation for Capacitive Current in Urban Distribution Network

城市配电网中电缆出线日益增多,导致负荷低谷时出现容性无功倒送以及单相接地时故障电流过大.在理论分析和计算的基础上,利用MATLAB仿真平台下的电力系统工具箱搭建全电缆出线的变电站仿真模型.通过仿真模拟,确定补偿参数,综合治理后夜容性无功过剩及单相接地故障电流过大的问题.仿真结果表明:装设并联电抗器后,空载时母线处及短路时故障点的电容电流都有明显下降.同时也定量计算出不同电缆出线长度时所需电抗器的参数,为工程应用提供参考.

There are more and more cable lines in urban power distribution network,as a result,the capacitive reactive power is sent back when the load is light,and the fault current is very large when one phase is shortened.This paper established a model of a whole cable line transformer substation by using the PSB of MATLAB on the basis of the theoretical analysis and calculation.Through the simulation and reasonable selection of the parameters,the two problem are solved synthetically.The simulation results have shown that the capacitive current is reduced obviously at both the bus under no-Load and failure point.At the same time,the parameters of the required reactor when the length of cable line is different,which can provide reference for engineering applications.