基于补偿零序压差原理的110 kV线路纵向故障保护方案

110 kV Line Longitudinal Fault Protection Scheme Based on Compensated Zero Sequence Voltage Differential Principle

针对现有保护装置没有计及纵向故障的保护方案的问题,首先分析110 kV负荷站变压器中性点接地和不接地方式下线路的单相、两相断线故障特征。其次依据断线故障特征提出了基于线路双端零序电气量的补偿零序电压差动原理的断线保护方案,实现了断线故障的快速可靠动作。最后在110 kV纵联差动保护装置上增加断线保护逻辑,并在数字仿真系统上建立110 kV负荷站输电系统,验证了所提断线保护方案的有效性。

In view of the lack of protection scheme for longitudinal fault in existing protection device,firstly,the characteristics of single-phase and two-phase line broken faults of the line are analyzed under the neutral point grounding and ungrounded modes of the transformer in 110kV load station.Secondly,according to the characteristics of line breaking faults,line break protection based on the compensation of zero sequence voltage differential principle of double terminal zero sequence electrical quantity is proposed to realize the fast and reliable action of line disconnecttion fault.Finally,the disconnection protection logic is added to 110 kV longitudinal differential protection device,and the transmission system of 110 kV load station is established on digital simulation system,which verifies the effectiveness of disconnection protection.