PERMANENT MAGNET INDUCED ELECTRIC MACHINE AND METHOD FOR OPERATING SUCH A MACHINE

摘要

If a winding short-circuit occurs in a stator coil winding of a permanent magnet induced electric machine, a short-circuit current is produced in said winding that results in an electrically induced magnetic alternating flux whose value corresponds to the permanent magnetic alternating flux flowing through the respective winding and which is opposite in phase. Such a short- circuit current could lead to a burn-down of the winding due to its considerable strength and the loss associated therewith. The aim of the invention is to prevent such a burn-down. To this end, the coil affected by the short-circuit is short-circuited as a whole or is impinged upon with a corresponding in-phase current as soon as a winding short-circuit is detecte d. The entire short-circuit current in the coil reduces the excessive short- circuit current in the individual winding or in the individual winding section, whereby the respective winding part can be prevented from burning down.