风电场集电线路精细化保护研究

Research on precise protection of wind farm collector line

为解决风电场集电线路保护存在的快速性和选择性问题,提出了基于单端电气量的风电场集电线路保护方案。集电线路上新增两套无通道保护,满足集电线路故障双端快速隔离。基于正常运行潮流方向和故障方向的不同,提出了单套保护自适应故障位置判据,满足了单套保护同时保护系统侧和风机侧故障的苛刻需求;干线和风机故障有选择隔离时间判据和满足并网点区段故障快速隔离电流判据;提出了不对称故障利用对端断路器动作信息的区段隔离判据和集电线路出口保护整定值的改进方案,并利用出口三段式保护兼顾了集电线路后备保护的需求,满足了风电场集电线路故障有选择、快速和可靠的隔离要求。

In order to solve the rapidity and selectivity of wind farm collector line protection,a wind farm collector line protection scheme based on single-ended electrical quantity is proposed.Two sets of No-Communication protection have been added to the collector line to realize the rapid isolation of the two-ended fault of the collector line.Based on the different power flow direction and fault direction of normal operation,the adaptive fault position criterion of a single set of protection is proposed,which realizes the demanding requirements that a single set of protection can protect the fault of the system side and the fan side at the same time.The selective isolation time criterion for trunk line and fan faults and the fast isolation current criterion for meeting the faults of the grid-connected section are proposed.An improved scheme for the section isolation criterion of asymmetric fault utilization of the action information of the end circuit breaker and the setting value of the outlet protection of the collector line is proposed,and the three-stage protection of the outlet is used to take into account the needs of the backup protection of the collector line,which meets the requirements of selective,fast and reliable isolation of collector line faults in wind farms.