A rail vehicle power supply system adapted to supply power to at least two motors (28, 30) via their respective inverters (32, 34) in a power train, the power supply system comprising at least two DC power transmission buses (24, 26) connected in parallel, each of said transmission buses (24, 26) being adapted to supply power to one of said motors (28, 30) via its respective inverter (32, 34), the system being adapted to be connected to a first power source and a second power source, each transmission bus (24, 26) comprising an input impedance filter inductance (42, 46) for achieving a given input impedance for the drive train, comprising a plurality of switches (48, 58, 66, 68) and a first source circuit breaker for configuring a first mode of operation using the first power source or a second mode of operation using the second power source, said first power source being a catenary and said second power source comprising a plurality of autonomous power sources (18, 20) on board said railway vehicle, each autonomous power source (18, 20) being connected, in the second mode of operation, via a respective switch (66, 68) of the plurality of switches, which switch is referred to as a second source switch, to one of the DC power buses (24, 26), via a point (50, 60) forming part of that DC power bus (24, 26), located at the input of the respective inverter (32, 34), to supply DC power to each DC power bus (24, 26), said first source circuit breaker being connected between the first power source and said DC power transmission buses (24, 26), and adapted to connect and disconnect the power system to the first power source, characterised in that: the output of the first source circuit breaker is connected to a plurality of branches, each branch comprising at least one of said input impedance filter inductors (42, 46), at the output of which is connected a respective switch (48, 58) of the plurality of switches, referred to as a branch switch per branch, the output of which is connected to a respective one of said points (50, 60) forming part of one of said DC power transmission buses at the input of the respective inverter (32, 34), each of the DC power bus input impedance filter inductors (42, 46) being sized to provide a connection of the DC power buses (24, 26) without resonance in each of the first and second modes of operation. comprising a plurality of switches (48, 58, 66, 68) and a first source circuit breaker for configuring a first mode of operation using the first power source or a second mode of operation using the second power source, said first power source being a catenary and said second power source comprising a plurality of autonomous power sources (18, 20) on board said railway vehicle, each autonomous power source (18, 20) being connected, in the second mode of operation, via a respective switch (66, 68) of the plurality of switches, which switch is referred to as a second source switch, to one of the DC power buses (24, 26), via a point (50, 60) forming part of that DC power bus (24, 26), located at the input of the respective inverter (32, 34), to supply DC power to each DC power bus (24, 26), said first source circuit breaker being connected between the first power source and said DC power transmission buses (24, 26), and adapted to connect and disconnect the power system to the first power source, characterised in that: the output of the first source circuit breaker is connected to a plurality of branches, each branch comprising at least one of said input impedance filter inductors (42, 46), at the output of which is connected a respective switch (48, 58) of the plurality of switches, referred to as a branch switch per branch, the output of which is connected to a respective one of said points (50, 60) forming part of one of said DC power transmission buses at the input of the respective inverter (32, 34), each of the DC power bus input impedance filter inductors (42, 46) being sized to provide a connection of the DC power buses (24, 26) without resonance in each of the first and second modes of operation. the output of the first source circuit breaker is connected to a plurality of branches, each branch comprising at least one of said input impedance filter inductors (42, 46), at the output of which is connected a respective switch (48, 58) of the plurality of switches, referred to as a branch switch per branch, the output of which is connected to a respective one of said points (50, 60) forming part of one of said DC power transmission buses at the input of the respective inverter (32, 34), each of the DC power bus input impedance filter inductors (42, 46) being sized to provide a connection of the DC power buses (24, 26) without resonance in each of the first and second modes of operation.