A Comprehensive Review of Fundamental Harmonic Approximation Analysis Techniques for Series-Parallel Resonant Converters with Capacitive Filter

Due to its voltage-fed nature and capacitive output filter, rear-end rectifier (RER) of series-parallel resonant converters with capacitive filters draw discontinuous currents. Not only simple and elegant techniques such as Fundamental Harmonic Approximation (FHA) analysis, but also time domain, state space and state-plane approaches also fail to model such converters with reduced labor. A recent study introduced technique to restore the simplicity of FHA analysis concerning such converters. Therefore, detailed discussion of available FHA modelling techniques in relation to series-parallel resonant converters with capacitive filters and their comparison is presented in this paper.