高灵敏度和高区分度电压暂降能量指标研究

Research on voltage sag energy index with high sensitivity and discrimination

中文关键词  灵敏度  区分度  电压暂降  能量指标  严重程度

英文关键词  sensitivity  discrimination  voltage sag  sag energy index  severity

中文摘要

      现有电压暂降能量指标(sag energy index, SEI)的定义中仅使用电压参数, 用于电压暂降严重程度评估时灵 敏度和区分度较低. 结合电压暂降期间的故障电流、故障电压和稳态电流, 提出一种电压和电流融合的新型SEI; 构 建电压暂降传播模型, 从理论角度对比分析现有SEI和新型SEI在故障电阻、故障距离方面的灵敏度和区分度; 基于 典型电网拓扑, 验证新型SEI在电压暂降严重性评估时灵敏度和区分度的优越性, 利用蒙特卡洛模拟预估法, 验证新 型SEI用于电网电压暂降严重程度评估的有效性. 结果表明: 新型SEI克服了现有SEI灵敏度和区分度方面的不足; 利用新型SEI可有效评估电网的电压暂降严重程度, 有助于电网脆弱区域的识别.

英文摘要

      The current voltage sag energy indexes (SEI) are constructed using only voltage parameters, their sensitivity and discrimination are low when used for voltage sags severity evaluating. A new type of SEI is proposed combining the steady-state current, fault current and fault voltage during the voltage sag. A voltage sag propagation model is constructed, the sensitivity and discrimination between the existing and the new SEI are theoretically analyzed in terms of fault resistance and distance. Based on the typical power grid topology, the superiority of the new SEI in sensitivity and discrimination is verified, and the Monte Carlo simulation prediction method is used to verify the effectiveness of the new SEI used for voltage sag severity evaluation. The simulation results show that the new SEI overcomes the shortcomings of the existing one in sensitivity and discrimination. And it can be used to assess the severity of the voltage sag effectively, which is helpful for identifying the vulnerable areas of the power grid.