CAJ | 학술논문

在异步互联电网和交直流并联电网中研究了短路比系列指标与直流故障引起的受端交流电网稳态电压跌落之间的定量关系。结果表明在异步联网系统中，直流短路比指标能有效地定量指示出直流故障下交流电网的电压支撑能力，而在交直流并联电网中则不能。针对交直流并联电网，提出了改进短路比指标的思路和新指标。仿真结果表明，改进短路比指标能够有效地定量指示出交直流并联电网中直流闭锁引起的交流母线稳态电压跌落水平。
재이보호련전망화교직류병련전망중연구료단로비계렬지표여직류고장인기적수단교류전망은태전압질락지간적정량관계。결과표명재이보련망계통중，직류단로비지표능유효지정량지시출직류고장하교류전망적전압지탱능력，이재교직류병련전망중칙불능。침대교직류병련전망，제출료개진단로비지표적사로화신지표。방진결과표명，개진단로비지표능구유효지정량지시출교직류병련전망중직류폐쇄인기적교류모선은태전압질낙수평。
In the environment of AC/DC parallel power grid and asynchronously interconnected power grid the quantitative relation between steady state voltage dips caused by faults occurred in HVDC transmission system and series indices of short-circuit ratio （SCR） is researched. The obtained results show that in asynchronously interconnected system, HVDC SCR indices can effectively and quantitatively indicates the voltage supporting strength of AC power grid under faults occurred in HVDC system; however such HVDC SCR indices cannot play a similar part in AC/DC parallel power grid. Thus for AC/DC parallel power grid, a thinking and corresponding improved new SCR indices are proposed. Simulation results show that the improved SCR indices can quantitatively indicate the steady state voltage dip of AC busbar caused by DC block faults occurred in AC/DC parallel power grid.