Magnetic design and experimental evaluation of Integrated Magnetic Components used in Interleaved Multi-phase DC/DC converter with Phase Drive Control

Interleaved Multi-phase DC/DC Converters (IMDDC) with Integrated Magnetic Components (IMC) are well-known as one of the converter topologies that can achieve high-power-density. However, as one of the drawbacks of IMDDCs, the power conversion efficiency when all phases are driven may decrease between light and middle loads. The main causes of the efficiency reduction are non-load losses caused by parasitic capacitances in power devices and magnetic components. These losses especially increase under higher switching frequency and hard switching condition. To deal with this problem, IMDDCs with Phase Drive Control (PDC) has already been proposed as an attractive control scheme which can improve power conversion efficiency in all load ranges, by changing the number of drive phases. However, employing PDC in IMDDCs with IMC comes with two main drawbacks: 1) Magnetic saturation may occur due to the biased magnetization while driving a single-phase. 2) The circulating current flow in the anti-parallel diode of off-switch reduces the power conversion efficiency. Therefore, to overcome these problems, this paper proposes a novel design method of IMCs used in IMDDCs with PDC. The effectiveness of the proposed design method is discussed from theoretical and experimental viewpoints.