Electric traction system for a railway vehicle and protection method realized by such a system

A securing method implemented in an electric traction system for a railway vehicle, comprising:

• a synchronous electric traction machine having a plurality of phases;
• and,
• a power supply circuit, the power supply circuit including a converter, connected to a DC voltage source and delivering a polyphase voltage adapted to power the synchronous electric traction machine to which the converter is connected by a plurality of electric cables, an insulator and an electrical connector configured to be capable of short-circuiting the phases of the synchronous electric traction machines, placed downstream from the insulator,
• the synchronous electric traction machine further comprising a converter control, a primary detector for detecting an over-current in a plurality of output branches of the converter, and an actuator configured to actuate an opening of the insulator upon reception of a primary detection signal emitted by the primary detector,
• wherein the electric traction system further includes a secondary detector for detecting a fault of a short-circuit type downstream from the insulator and emitting a secondary detection signal toward the actuator,
• and wherein the actuator actuates a closing of the electrical connector for short-circuiting the phases of the synchronous electric traction machine upon reception of the secondary detection signal, on the condition the actuator has already received the primary detection signal emitted by the primary detector and having led to actuating the opening of the insulator
• wherein the secondary detector include at least one temperature sensor, for measuring a temperature corresponding to an internal temperature of the synchronous electric traction machine,
• wherein the securing method includes the steps successively consisting of:
• detecting an overvoltage in at least one output branch of the converter;
• actuating the opening of the insulator;
• then detecting a fault of the short-circuit type downstream from the insulator;
• and, in the affirmative,
• actuating the closing of the electrical connector for short-circuiting the phases of the synchronous electric traction machine.