Research on a static excitation control method for the high-power induction generator with a H-bridge cascaded converter topology

Aiming at the excitation control of a 12/3 phase dual stator-winding induction generator (DWIG), an excitation control method under the dq frame is proposed and analyzed based on a two unit H-bridge cascaded multilevel converter. Using the method, the voltage across the DC-side capacitor of the static var compensator can come to balance and the total output current can keep out of the influence to excitation current. Comparing with the traditional DC-side capacitor voltage balancing method by phase shifting, the proposed method can get to the absolute decoupling between the balance control of DC-side capacitor voltage and the control of excitation current. The validity of the proposed method is demonstrated by theoretical analysis and simulation.