Power supply for the Atlantic TGV high speed line

The author discusses the 2×25 kV AT (autotransformer) system chosen for the Atlantic TGV lines. The system has two essential advantages: control of the current return circuit and less induced interference on weak current lines; and fewer voltage drops on the line because power is transmitted under 50 kV between the substation and autotransformers; impedance in the power feed circuit is lower therefore and substations are spaced two to two and a half times farther apart than with 25 kV single-phase AC for equal performance levels. The author discusses the HV power supply for single-phase substations, substation design and implementation, OCS feeder line power feed, and features of the electrical equipment