A Pseudodecoupled Modeling and Analysis Method for Interleaved Multiphase Converters With Coupled Inductors

Interleaved multiphase converters with coupled inductors (MCCIs), which can increase the power density of switching power supplies, is a research hotspot in power electronics. However, it is difficult to obtain ideal symmetrical coupled inductors due to manufacturing inaccuracies, especially in high-power applications. Asymmetrical coupling of inductors will lead to phase imbalance in MCCIs and difficulty in circuit analysis. To address this, this article proposes a novel modeling method for MCCIs, extendable to the analysis of interleaved multiphase converters with asymmetrical coupled inductors. This helps to simplify the analysis of MCCIs and allows easier and more efficient controller and inductor design for MCCIs. First, the concept of pseudodecoupled equivalent circuits for MCCIs is presented, which solves the problem of modeling MCCIs. Second, the transient behavior and steady-state current ripple performance of MCCIs are analyzed based on the pseudodecoupled method. Third, the effect of the degree of inductance asymmetry on the MCCI performance is quantitatively analyzed. Then, the feasibility of extending PWM phase sequence and phase-shift adjustment methods to MCCIs is further verified using the proposed modeling approach, which can reduce the current ripple. Finally, the accuracy of the modeling and analysis methods is verified by simulation and experiment.