An Iterative-Based Dead-Time Compensation Method for Integrated Interleaved Boost-LLC Converter

This paper proposes an iterative-based dead-time compensation method to help integrated interleaved boost-LLC converter (IIBLLC) converter achieve higher frequency. By adjusting switching frequency and compensating dead time, the converter can operate in quasi-resonant mode and the rectification control signal is synchronized with the primary side. In quasi-resonant mode, smaller current RMS results in lower conduction losses and the advantages of realizing ZCS on the secondary side can be preserved. Finally, a 400 W / 850 kHz IIBLLC prototype with 36 – 60 V input and 12 V output is demonstrated, which achieves a peak efficiency of 96.2%. The experimental results show that the LLC operates in quasi-resonant mode, and the efficiency and power density are improved.