A study on a preventive system of wire break triggered by direct lightning strokes on to DC railway feeding systems

The wires of DC electric railway feeding circuit may be broken by a direct lightning stroke. This kind of trouble occurs not so frequently; however, once it occurs, it makes a great disturbance of train operation. We assumed the process of wire break, and we are now studying a new preventive system of wire break caused by ground faults triggered by lightning strokes. The result of basic test shows the possibility of detecting such ground faults before the break of the wire; however, there remain some problems which should be solved before practical system construction.