System and process for power supply to a railway vehicle, converter, control unit, and air-conditioning unit for the system

A power supply system for a railway vehicle having a plurality of cars comprising:

• a first electrical converter including a module;
• a second electrical converter, the first and second electrical converters transforming a single phase or direct electric voltage received via a catenary into a three-phase electrical voltage delivered to a first three-phase power supply network and a second three-phase power supply network respectively on board the railway vehicle, the first and second electrical converters distributing electrical power to the plurality of cars, the first and second power supply networks being electrically isolatable from one another;
• at least one air-conditioning unit installed in each of the plurality of cars, each air-conditioning unit including at least one compressor producing cold air expelled into an interior of the car, the at least one compressor electrically connected to the first three-phase power supply network and receiving three-phase voltage power from the first converter;
• and
• a plurality of auxiliary electrical loads other than the one compressors electrically connected to the second power supply network to be powered with three-phase voltage by the second converter;
• a third network for transmitting from each air-conditioning unit to the first electrical converter the respective demands of each air-conditioning unit, each demand indicating the electrical power required by each air-conditioning unit to cool or dehumidify the air within the car of the air-conditioning unit,
• the module adjusting both the amplitude of the three-phase voltage and the frequency of the three-phase voltage delivered by the first power supply network in response to the demands transmitted by the air-conditioning units.