芦嵊直流无功优化方案仿真研究

Simulation Study on Lu-Sheng HVDC Reactive Power Optimization Scheme

芦嵊直流正送时是一个典型的受端弱电网的直流输电工程。嵊泗电网的有效短路比仅为0.913,在芦嵊直流双极每极投入一台30 Mvar调相机以后,短路比可以达到6.1表现为强系统,芦嵊直流可以稳定运行。但是随着调相机的老化,故障率越来越高已经影响到芦嵊直流的安全稳定运行。当只有一台调相机运行并且嵊泗电网处于孤岛运行情况下,有效短路比为2.81处于临界状态。为了保证在孤岛情况下一台调相机运行时嵊泗站的无功和电压的稳定性考虑增加一台无功补偿设备。文中通过比较不同的无功补偿方案的优缺点,对在嵊泗换流站母线上加装一台SVC或SVG进行了详细的仿真研究。仿真结果表明加装SVG比加装SVC能更好地提高嵊泗电网的电压稳定性。

When power direct is normal, Lu-Sheng HVDC is a typical weak AC grid project. The ESCR of Shengsi grid is only 0.913. After each pole installed 30 Mvar synchronous compensator the SCR of Shengsi grid is 6.1. The behavior of Shengsi grid is strong system, the HVDC can running safety and stability. But as time goes on, the high failure rate of synchronous compensator have seriously affected on the Lu-Sheng HVDC safe and stable operation. When Shengsi grid in islanding mode and only one synchronous compensator operation, the ESCR only 2.81. In this case, need install one reactive power compensation equipment, in order to keep the reactive power and voltage stability. The paper study on different reactive power compensation scheme and detailed simulation study on the affect after installed SVC or SVG. The simulation results show that install SVG better than install SVC in improve the Shengsi grid voltage stability.