论文标题
通用短路比率用于不均匀多馈LCC-HVDC系统的网格强度评估
Generalized Short Circuit Ratio for Grid Strength Assessment in Inhomogeneous Multi-infeed LCC-HVDC Systems
论文作者
论文摘要
用于多馈性高压直流电（MIDC）系统的GIRD强度评估的广义短路比（GSCR）是传统短路比率（SCR）的严格理论扩展，它允许将使用SCR扩展到MIDC系统的大量经验。但是，GSCR最初是基于同质MIDC系统的假设得出的，在该假设中，所有HVDC转换器都具有相同的控制配置，这对GSCR对不均匀MIDC系统的应用构成了挑战。为了削弱这一假设，该字母应用了模态扰动理论，以探索将GSCR应用于不均匀MIDC系统中的可能性。数值实验的结果表明，在不均匀的MIDC系统中，先前提出的GSCR仍然可以使用而无需修改，但是需要通过考虑HVDC转换器控制配置的特性来重新定义关键GSCR（CGSCR）。因此，GSCR和重新定义的CGSCR之间的差异可以有效地量化相关的AC网格强度，从而在静态电压稳定性范围内量化。我们提出的方法的性能在三重馈送的非均匀LCC-HVDC系统中得到了证明。
Generalized short circuit ratio (gSCR) for gird strength assessment of multi-infeed high voltage direct current (MIDC) systems is a rigorous theoretical extension of traditional short circuit ratio (SCR), which allows the considerable experience of using SCR to be extended to MIDC systems. However, gSCR was originally derived based on the assumption of homogeneous MIDC systems, where all HVDC converters have an identical control configuration, which poses challenges to the applications of gSCR to inhomogeneous MIDC systems. To weaken this assumption, this letter applies modal perturbation theory to explore the possibility of applying gSCR in inhomogeneous MIDC systems. Results of numerical experiments show that, in inhomogeneous MIDC systems, the previously proposed gSCR can still be used without modification, but critical gSCR (CgSCR) needs to be redefined by considering the characteristics of HVDC converter control configurations. Accordingly, the difference between gSCR and redefined CgSCR can effectively quantify the pertinent ac grid strength in terms of static voltage stability margin. The performance of our proposed method is demonstrated in a triple-infeed inhomogeneous LCC-HVDC system.
