[Accepted L1 Paper] Spread Spectrum Technique Employing Phase-Shift Modulation to Reduce EM Noise for Parallel-Series LLC Resonant Converter
Journal title: IEEE Transactions on Power Electronics (5-yr IF: 7.710, IF: 7.151, 4.23%, L1)
Article title: Spread Spectrum Technique Employing Phase-Shift Modulation to Reduce EM Noise for Parallel-Series LLC Resonant Converter
Authors: Hwa-Pyeong Park, Mina Kim and Jee-Hoon Jung*
A spread spectrum technique (SST) has been developed to mitigate an electromagnetic interference (EMI) in power converters. However, for resonant converters using a pulse frequency modulation (PFM), it is difficult to regulate its output voltage with the SST, because the switching frequency variation according to the spread spectrum induces large output voltage fluctuation. In this paper, an enhanced phase-shift algorithm of the frequency modulation of the SST and a parallel-series structure for a LLC resonant converter are proposed to obtain tight output voltage regulation under the spread spectrum operation. The performance of the proposed methods is experimentally verified using a 600 W prototype parallel-series LLC resonant converter.