提出了一种新的微电网内部故障区域判定方法,采取微电网发生内部故障时首先断开静态开关的故障隔离策略.由于微电网内部发生故障与断开静态开关都会引起微电网内各线路的电流发生变化,利用故障线路与非故障线路在两次电流变化中存在明显差异的特征,实现对故障区域的准确判断.当检测到两次电流突变量均大于设定值时,即认为故障发生在保护区域内.理论分析与PSCAD/EMTDC系统仿真验证了该微电网故障区域判定方法的有效性和可行性.
A novel method of fault location inside the micro-grid is proposed. The fault isolation policy that the static switch operates first in case of internal fault is adopted. An internal failure and the subsequent static switch operation will cause line current changes within the system, and the significant difference of current changes between faulted lines and normal lines can be applied to locate the fault zone accurately. The fault can be determined inside the protect- ing zone when the current fault component is detected above the presetting value twice. Theoretical analysis and system simulation results of PSCAD/EMTDC validate the effectiveness and feasibility of the proposed method.