System for powering an element among a rotor and a stator of an electric machine, and method for controlling such a system

摘要

The system has a converter (30) for converting a direct input current into a polyphase alternating output current. The converter delivers the polyphase current to an element (18). A control unit (32) controls the converter. A storage bank (34) comprises storage capacitors (66, 68) placed between the input terminals of the converter. A protective device protects the element from over-voltages or over-currents of the polyphase current. The control unit applies a negative voltage to terminals of a thyristor (78) during a time period greater than a predetermined turn-off time of the thyristor. Independent claims are also included for the following: (1) an electric traction chain comprising an electric machine (2) a control method.