Simultaneous Power and Data Modulation Scheme for LLC Resonant Converter

Power and signal dual modulation (PSDM) integrates communication functions in power converters, providing an appropriate communication method for power electronics systems. This article discusses the theory and implementation of PSDM in resonant converters. The data are modulated into a resonant converter's gate signal and then transmitted along with power. The fundamental principles of the proposed PSDM modulation are analyzed in detail, and a novel PSDM scheme is proposed. The decoupling between data modulation and power control is realized in the communication process. Furthermore, the design considerations of converter parameters regarding their influence on the output voltage gain are given to evaluate the reliability of the proposed PSDM scheme. Finally, a 500 W prototype with a resonant frequency of 180 kHz is set up, and the experiment achieves a 4.5 kbps bitrate using the proposed modulation scheme, demonstrating the correctness of the scheme.