Impact of Magnetics Tolerance on the Power Sharing of Parallel Dual-Output Phase-Shift Full-Bridge Converters

Understanding the effects of circuit element tolerances on power electronic devices is crucial for ensuring optimal performance and system reliability. Therefore, this paper explores the impact of magnetic tolerance in a parallel dual-output phase-shift full-bridge converter. Initially, a comprehensive analysis of power sharing among the individual legs on the converter’s secondary side is provided. Taking into account ±20% uniform tolerances in inductance, a rigorous mathematical derivation of the probability density function for the converter’s secondary-side leg power and for its partial-scale bridge power is provided. The outcomes of this derivation lead to a simplified triangular distribution for each leg, while an Irwin-Hall distribution for each bridge. These theoretical developments are further strengthened by numerical validation through extensive 30k PLECS simulations, incorporating randomized inductance parameters. The results of this validation process affirm the effectiveness of the adopted approach in accurately predicting power-sharing outcomes.