摘要 |
A system for switching and chopping DC current flowing through the windings of an electric machine, characterized in that the system comprises: a smoothing reactor common to the various windings; supply thyristors interposed between the winding ends and one of the poles of the power supply; freewheeling thyristors connected, like the first-mentioned thyristors, to the winding ends and to a common connection of a freewheeling circuit made by way inter alia of the smoothing reactor, at least one winding and the corresponding freewheeling thyristor; and a system for controlling the switch and driving the thyristor control electrodes so as to initiate the chopping or switching operations, with the intervention of the freewheeling circuit, in dependence upon the value of the control parameters. |