Method for deicing a power supply line for railway vehicles

1. A method for deicing a direct current power supply line for railway vehicles, said line extending between at least a first and a second reversible substations able to supply an electrical current circulating on the electrical power supply line, the first substation being controlled in a current supply mode, to supply an electrical current to the electrical power supply line and the second substation being controlled in a current recovery mode, to recover the electrical current from the electrical power supply line and send it back on an electrical power supply network, the method comprising:

establishing a voltage difference between the output terminals of the first and second substations such that a current circulates on the electrical power supply line between the first substation and the second substations and that the heat produced by the circulation of the current causes the deicing of the power supply line between the first and second substations.

2. The deicing method according to claim 1 further comprising:

choosing and controlling the voltage difference between the output terminals of the first and second substations.

3. The deicing method according to claim 1 , wherein the first substation and the second substation each comprises a reversible power converter, such that the first substation and the second substations are capable of operating in current supply mode or current recovery mode and in that the method further comprises controlling the operating mode of the first and second substations, in current supply mode and current recovery mode, respectively.

4. The deicing method according to claim 3 , wherein the reversible power converter comprises a rectifier and an inverter, connected to the rectifier in anti-parallel, and in that the first or second substation operates in inverter mode when it is controlled in current recovery mode and in rectifier mode when it is controlled in current supply mode.

5. The deicing method according to claim 1 , wherein each substation is connected to the power supply line and to a rail such that the current circulates in a loop passing successively through the substation controlled in current supply mode, then through the power supply line, then through the substation controlled in current recovery mode, then through the rail to return to the substation controlled in current supply mode.

6. The deicing method according to claim 1 further comprising measuring the temperature on or near the power supply line, the voltage difference being established if the measured temperature is below a pre-established threshold.

7. The deicing method according to claim 1 further comprising checking if a railway vehicle circulates between the substations, the voltage difference being established if no railway vehicle is circulating between the first and second substations.

8. The deicing method according to claim 1 further comprising:

choosing two substations to be controlled in current supply mode and current recovery mode, respectively, and

establishing a voltage difference between the output terminals of said substations depending on the segment of the line to be deiced when the power supply line extends between more than two substations.