This digest presents a novel resonant tank design for dual-phase LLC DC-DC converters in Auxiliary Power Module (APM) applications. The proposed design ensures that the impedance of one phase is always either larger or smaller than that of the other phase over a wide range of input and output voltages. Consequently, only one Switched Controlled Capacitor (SCC) circuit is required to achieve current sharing across the load range, thereby reducing system complexity and implementation costs without compromising efficiency or current-sharing performance. The design procedure is explained, including tolerance analysis, and experimental results from a full-scale, GaN-based 4-kW APM demonstrate the effectiveness of this design approach for dual-phase LLC converters in maintaining current sharing across varying input/output voltages and load ranges.
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