Patent ID: 9590547
Date: 2017-03-07
CPC Classifications: F03D,H02H,H02J,H02P,Y02E

Claim:
1. A method of operating a converter for a double fed induction generator (DFIG), the converter including a rotor side converter comprising a plurality of rotor side AC connections, a first damping circuit including a first damping resistor with a first terminal connected to a first rotor side AC connection of the rotor side converter and a second terminal connected to a first rotor lead of the DFIG, the first damping circuit including a first damping switching circuit connected in parallel with the first damping resistor, the first damping switching circuit including a first terminal connected to the first terminal of the first damping resistor and a second terminal connected to the second terminal of the first damping resistor, the converter further including a plurality of rotor side DC connections coupled with a DC circuit, and a grid side converter comprising a plurality of grid side DC connections coupled with the DC circuit and a plurality of grid side AC connections coupleable to stator leads of the DFIG, the method comprising: selectively activating the first damping circuit to conduct current through the first damping resistor between the first rotor lead and the first rotor side AC connection in response to a grid fault occurrence or a grid fault clearance; and selectively bypassing the first damping resistor to prevent current flow in the first damping resistor a time period after activating the damping circuit.