Method and device for operating double fed ac machine in particular in a wind power station

摘要

The method involves operating the machine (1) with an intermediate d.c. circuit inverter (4) in the rotor circuit by operating it as a dual feed asynchronous machine in normal operation and as an asynchronous machine with a short circuited rotor in the low power range by isolating the rotor (3) from the inverter and short circuiting it and changing the stator (2) over from the mains (14) to the inverter. An independent claim is also included for the following: (a) a wind power system with a polyphase machine, especially generator.