A field-to-line coupling model for overvoltage analysis in light-rail transit DC traction power systems

This paper faces the problem of the protection against overvoltages of atmospheric origin for modern electric mass-transit systems such as light-rail transportation systems (LRTS) and proposes a transmission-line (TL) model for the field-to-line coupling, which allows to evaluate the response of the supply system of a typical LRTS to a generic electromagnetic field. The incident-field excitation has been modeled in the time domain by means of a plane wave and the method of characteristics has been applied in order to solve the resulting partial differential equation (PDE) system. The developed model has been implemented into the electromagnetic code PSCAD-EMTDC and several simulations have been performed in order to determine the "optimal" configuration in terms of locations of the surge arresters for the overvoltage protection system.