Control Strategies Generation Mechanism for LLC Resonant Converter

As one of the most popular DC/DC converters, recently, numerous of control strategies have been developed for LLC resonant converter. However, an insight investigation on the generation mechanisms and categorizations of existing control strategies are still lack in the literature. Thus, the main objective of this paper is to investigate the control strategy generation mechanisms of LLC converter based on the simple fundamental harmonic analysis (FHA). According to the analysis in this paper, the existing control strategies for LLC converter can be divided into the following three groups: 1) control strategies by adjusting input voltage; 2) control strategies by adjusting resonant tank components values; and 3) control strategies by adjusting the secondary impedance. This paper will provide an insight analysis of the LLC converter control strategy generation mechanisms, and can inspire readers to develop novel control strategies.