变压器相间短路后备保护中负序阻抗继电器应用探讨

偏移特性阻抗继电器应用于变压器相间短路后备保护时,其灵敏性和可靠性往往不能满足要求。文中提出负序阻抗继电器,其测量阻抗不受变压器Y,d接线的影响,能避开负荷阻抗,且在电压互感器和电流互感器断线时能有效地闭锁。应用Simulink建立仿真模型验证负序阻抗继电器的性能,仿真结果表明：负序阻抗继电器在各种情况下的相间短路时均...

Application of Negative Sequence Impedance Relay in Backup Protection for Transformer Phase-to-phase Faults

When the impedance relay with offset characteristic is applied to the backup protection for transformer phase-to-phase faults,its reliability and sensitivity always cannot meet the requirement.A negative sequence impedance relay(NSIR) is presented.Its measuring impedance is not dependent on phase shift of the Y,d connection of the transformer and it can lock effectively while line broken happened to potential transformer or current transformer.Simulink model used to verify performance of NSIR is built.Simulation results show that NSIR can act reliably when various phase-to-phase short circuit faults take place,and it also proves with an engineering practical example that NSIR is a sensitive and reliable backup protection for transformer phase-to-phase faults.