大规模新能源接入电网连锁故障预防控制策略研究

Study of strategy to prevent and control power grid cascading failure connecting large-scale new energy

本文着眼于大规模新能源接入的电网连锁故障预防控制策略研究,在深入分析大规模新能源接入对电网连锁故障影响机理的基础上,提出了适应含大规模新能源的电网连锁故障预防控制策略。该控制策略采用直流灵敏度法甄选出高危线路,并计算出发电功率转移分布系数矩阵,继而采用反向等量配对法,根据发电功率转移分布系数调整发电机组的出力,使得高危线路的负载率得到有效下降,同时保证其他线路负载率维持在重载阈值以下,改善潮流分布,起到预防连锁故障发生的作用。最后通过甘肃酒泉地区电网的仿真分析,进一步揭示了大规模新能源接入对电网连锁故障的影响机理;验证了本文提出的连锁故障控制策略的有效性。

This article aims to prevent and control cascading failures of power grid connecting large-scale new energy sources. Based on analysis of the cascading failures mechanism influenced by large-scale new energy grid-connection,a strategy to prevent and control cascading failure was proposed,which can adapt to the massive new energy grid-connection. It is based on the DC sensitivity method to identify the critical lines of cascading failures which is also the first failure,and to calculate generation shift distribution factor（ GSDF） matrix,then to adjust the power of unit according to GSDF matrix. This strategy formulates the adjustment of generators＇ active power according to the sensitivity analysis and to the reverse same-amount pairing principle,in order to improve the power flow distribution of the system and prevent the occurrence of cascading failures. Finally,the cascading failures mechanism influenced by large-scale new energy grid-connected is further revealed by simulating the Jiuquan grid,and the strategy proposed is validated.