Protection scheme for out-of-phase short-circuit fault of traction feeding network

Pantograph of an en-energized train may never run through n neutral section. As it does so, the arc generated across the pantograph will likely short the two feeding lines together at both sides of the neutral section where two phases are separated, The fault is called out-of-phase short-circuit fault for which short two out-of-phase feeding lines. Traditional feeder distance protection and current protection may likely misoperate in this condition. This paper briefly describes the overlap-structure neutral section used in the high-speed railway, compared with insulator-structure neutral section. Then the reason why feeder distance protection and overcurrent protection cannot protect against out-of-phase short-circuit is discussed. Finally, a protection scheme for out-of-phase short-circuit fault is introduced, which using the voltage difference between two busbars and the current through faulted feeder line. A simulation model built up in MATLAB/Simulink is used to validate the introduced protection scheme.