ADIF has awarded Eiffage Energía, as part of a temporary joint venture with Telice S.A., the works and maintenance of the autotransformer and remote power control stations for the Pedralba-Orense section of the Madrid-Galicia AVE line, with a budget of more than 10 million euros. The works, which have just begun and are due to be completed in 9 months, consist of the construction of various autotransformer stations for the power supply system to the catenary planned by ADIF for the aforementioned High Speed section. The 2×25kV electrification system supplies power at a voltage of 50kV between the contact line and the feeder and the rolling stock draws power at a voltage of 25kV between the contact line and the rail, thus requiring the installation of autotransformers with a ratio of 55/27.5kV approximately every 15 kilometres. To house these autotransformers and their auxiliary equipment, facilities are to be built located close to the tracks, which will be of two types, depending on whether the autotransformers are installed close to the neutral zones between substations, sectioning autotransformer stations (SATS), or along the route, intermediate autotransformer stations (ATS). Each traction substation has its own area, including the autotransformer stations associated with the area substation, defined as the section of catenary that is powered by the substation in question in normal operating mode, not degraded mode. Regarding the maintenance, which will be carried out for 24 months, once the construction of each of the autotransformer stations has been completed, work will take place on the one hand in the form of  predictive maintenance, carried out at predetermined intervals or in accordance with established criteria and aimed at reducing the probability of failure or the degraded operation of an element; and on the other, corrective maintenance, carried out after the recognition of a fault and aimed at returning an element to a condition in which it can perform the required function.