A Three-Port Resonant PV Converter With Adaptive Resonant Time and Optimized Gain Adjustment Path

This article proposes a scheme to achieve improved efficiencies for a standalone photovoltaic system. Specifically, a combined three-port
LLC
structure is utilized to fulfill isolated resonant power conversion and battery management, and an auxiliary phase-controlled current is adaptively injected to adjust the
LLC
resonant state without adding extra power
mosfet
s. Also, the overall efficiency is improved by simultaneously optimizing the resonant time and the switching frequency, and the optimal operation points are continuously tracked by combining optimization presets with perturbation and observation control. Based on detailed theoretical analysis, experimental results verify the effectiveness of the proposed concept.