Patent ID: 7605487

Claim:
Method for operating a frequency converter ( 26 , 26 ′, 26 ″) of a generator ( 14 , 14 ′, 14 ″), in the event of a substantial grid voltage drop in a grid, wherein the frequency converter ( 26 , 26 ′, 26 ″) comprises a generator-side power converter ( 32 , 32 ′, 32 ″), to be connected to the generator ( 14 , 14 ′, 14 ″), a grid-side power converter ( 28 , 28 ′, 28 ″) to be connected to the grid ( 18 , 18 ′, 18 ″), and a DC link circuit ( 30 , 30 ′, 30 ″) for connecting the generator-side power converter ( 32 , 32 ′, 32 ″) to the grid-side power converter ( 28 , 28 ′, 28 ″), the method comprising the step of generating an amount of reactive current to be supplied to the grid ( 18 , 18 ′, 18 ″) by controlling the frequency converter ( 26 , 26 ′, 26 ″) so as to generate reactive current.