Hybrid Converter with Simultaneous DC and AC Outputs using Fuzzy Controllers

Abstract

A new control strategy for hybrid converter topology with a single DC input which gives both, DC and AC supply to corresponding DC and AC loads simultaneously is presented in this paper. This control strategy is realized by replacing the conventional PI controllers with Fuzzy logic controllers. Since the converter is derived from boost converter topology it is also called as Boost Derived Hybrid Converter (BHDC). The BDHC is controlled by unipolar sinusoidal pulse width modulation. This BDHC uses less number of switches and provides DC and AC output with higher reliability. The converter is designed for 400 Watts including both AC and DC power outputs. Due to better power processing ability, these type of converters are best suited for systems having AC as well DC loads. Since the BHDC converter dynamics is non-linear, the fuzzy controller is better option for control which is a nonlinear control technique. The feedback to fuzzy logic controller is error and change in error from the two different comparators which compares AC voltage and DC voltage with respective references. This controls the DC voltage more smoothly than just comparing error voltage. The simulation results demonstrate independent control of DC and AC output voltages in steady state of BDHC.