Patent ID: 7579702
Filing Date: 2009-08-25
Classification: H02J,H02P,Y02E

Abstract:
1. An electric power converting device for controlling doubly-fed induction generators, comprising: a doubly-fed induction generator, a power converter for converting electric energy of the doubly-fed induction generator for application to an alternate current (AC) system, a controller for PWM-controlling the power converter, and the AC system adapted to use an AC power supplied thereto from the power converter, wherein the doubly-fed induction generator further comprises: a synchronous generator for generating a separate auxiliary electric power independently of the doubly-fed induction generator; and an auxiliary converter for converting energy supplied thereto from the synchronous generator into a direct current (DC) power for application to the power converter, wherein the power converter includes: a generator-side converter for converting an AC power converted from electric energy of the doubly-fed induction generator into a DC power; a DC link capacitor connected to the generator-side converter in such a fashion as to be connected in parallel with the auxiliary converter, for storing electric energy; and a grid-side converter for re-converting the DC power converted by the generator-side converter into the AC power for application to the AC system, the DC link capacitor being disposed between the generator-side converter and the grid-side converter.