基于感抗比的并补装置电抗器匝间短路保护

Protection of Shunt Capacitance Compensator against Inter-turn Fault based on Impedance Ratio

并联电容补偿装置的电抗器发生匝间短路时,其电感值的变化将导致感抗比(电抗器的感抗与电容器容抗的比值)变化,利用该电气量的变化,提出并补装置基于感抗比的新匝间短路保护。基于PSCAD的仿真表明利用感抗比的匝间短路保护能够对匝间短路故障作出快速正确的判断,具有较高的灵敏度。

The shunt capacitance compensator is an imprtant equipment of power traction substation in electrified railway. The series-wound reactor on it lacks of necessary protection against inter-turn fault. The change of the value of the inductance will result in the variation of the impedance ratio（the ratio between the value of inductance and capacitance） when the fault occurs. Using the change of the parameter, a new protection against inter-turn fault based on the impedance is proposed. PSCAD simulation shows that the impedance ratio protection against inter-turn fault of the reactor can make judgement to this kind of fault quickly. And what is more, it has high sensitivity