Modeling and Analysis of Fractional-Order Full-Bridge LLC Resonant Converter

This paper deals with the analysis of fractional-order LLC resonant converter, and aims to extend the full-bridge LLC converter (FBLLC) from integer-order domain to fractional-order domain, and to demonstrate the mechanism of the influence of fractional-order inductance (FOI) and fractional-order capacitance (FOC) on the operating features of the FBLLC. Firstly, the circuit model of fractional-order FBLLC is built on the basis of fundamental wave approximation (FHA) method and the fractional calculus. The expression of input and output voltage gain is derived in detail based on KVL and KCL. Additionally, the relationship and changing law between the pure resistance curve of FBLLC and the fractional-order of components are also analyzed. Finally, the above theoretical analysis is verified by simulation results, and the FO-FBLLC presents more flexible and diverse operating features than the integer-order FBLLC converter.