大容量柔性直流输电系统接入对电网暂态稳定性影响分析

结合厦门柔性直流输电科技示范工程,分析大容量柔性直流输电系统接入对电网暂态稳定性影响机理,利用PSD-BPA暂态稳定仿真程序对大容量柔性直流输电系统接入电网后暂态稳定进行仿真分析。结果表明:柔性直流输电系统接入对交流电网单一故障暂态稳定影响不明显;柔性直流输送功率大小及短路比对暂态过程电压有影响。随着柔性直流输电系统向交流电网输送功率增大,电压稳定水平将提高,短路比越小,效果越明显。针对交直流混联电网安全稳定问题,提出相应的措施建议。

Influence of Large Capacity VSC-HVDC Transmission System on Transient Stability of Grid

Based on the voltage source converter-high voltage direct current (VSC-HVDC) demonstration project in Xiamen,this paper analyzes the influence mechanism of large capacity VSC-HVDC transmission system on transient stability in the AC grid,and uses PSD-BPA simulation tools to analyze the transient stability of power grid after large capacity VSC-HVDC transmission system access.The results show that there is no significant effect of VSC-HVDC on the transient stability of AC grid under single fault,while the active power of VSC-HVDC and the short circuit ratio (SCR) both have effects on the transient voltages.The system voltage stabilization level can be improved by increasing power transmission of VSC-HVDC to AC grid,and the smaller the short-circuit ratio is,the more obvious the effect is.In view of the safety and stability of AC/DC hybrid power grid,corresponding measures and suggestions are put forward.