Earthing, protection, miscellaneous [of railway power systems]

The considerable increase in recent years of the per unit power of trains as well as their frequency has led the SNCF to take steps to simplify substation traction current return and to limit dangerous parasite voltages which might occur at the level of the rails and the earth. The authors describe how the most effective protection consists of interlinking to the rails the largest number of meshed metallic structures between each other, by creating an equipotential earthing network