FCSC converter with symmetrical short duty cycle for variable frequency applications

This paper proposes a new control strategy for a FCSC (Forced commutated control series capacitor) converter for small scale standalone electric generators able to cope effectively with a wide range of frequency variations. This new technique uses a symmetrical switching pattern across the maximum current position. This offers more flexibility in terms of the range of possible ON times and reduces the required ON time of the converter switches, allowing operation at much higher frequencies. Simulation results demonstrate how the adoption of this new technique allows the FCSC converter to maintain high input power factors over a wide range of input frequencies.