基于故障隔离分析的合环运行配电网电源接线方式研究

Research on Power Connection Mode of the Closed-loop Operation Distribution Network Based on Fault Isolation

受限于短路电流超标,国内合环运行配电网的2路电源来自变电站同一段10(20)kV母线。随着限流电抗器技术的进步,采用供电可靠性更高的电源接线方式需求被提出。文章从配电网故障隔离角度,分析采用其他电源接线方式的合环运行配电网的短路电流特性和保护动作行为。从短路电流水平是否会随着电网规模扩大而超标、短路电流特性是否能满足电流保护选择性的基本要求、在提供充分故障隔离的技术措施的前提下能否保证最小范围内隔离故障等方面进行研究,通过比较得出合环运行配电网保持现有接线方式更优的结论。该研究结论供相关单位选取合环运行配电网电源接线方式时参考。

Limited by the short-circuit current exceeding the standard,the two-way power supply of the domestic closed-loop distribution network comes from the same section of the substation 10 (20) kV bus. With the development of current-limiting reactor technology,the requirement of a connection mode with higher power supply reliability has been presented. From the perspective of fault isolation in distribution network,this paper analyzes the short-circuit current characteristics and protective action behavior of the closed-loop operation distribution network using other power supply connection methods. Whether the short-circuit current level exceed the standard and the short-circuit current characteristics can meet the basic requirements for current protection selectivity,and whether the protection can ensure the isolation of faults in the minimum range by using adequate technical measures have been studied. It is concluded that the combined distribution network maintains the existing wiring method. The conclusion of this paper provides a reference for the relevant units to select the power connection mode of the distribution network.