Optimal Integrated Design of a Magnetically Coupled Interleaved H-Bridge

The application of wide-band gap semiconductors and their integration with other power electronics components (e.g., passives, gate drivers, sensing, thermal management) can meet the growing demand for volume reduction in power electronics systems. The design of such an integrated system is a complex multiphysics problem given the high number of variables to identify, objectives to optimize, and constraints to satisfy. Traditionally, this complex problem is approached subdividing the design in different steps, where in each step, the single components are designed and optimized independently from the others. This might clearly overlook the effect that the design choices of a single subsystem has on other subsystems, leading to suboptimal solutions. In this article, an automated design approach is proposed with the aim of maximizing power density whilst minimizing total losses. As a vessel to investigate the presented optimization workflow, the magnetically coupled interleaved H-bridge topology is chosen as an emblematic example of multivariable design problem. The first step of this approach consists of developing a loss model of the converter, which takes into account components physical dimensions, the temperature dependence, and the circuit parasitics. In the second step, these models are used within a nested optimization procedure in order to estimate the losses for multiple points of load. With the aim of validating both design approach and optimization results, three different optimal solutions have been deeply analyzed with commercial suit, prototyped, and tested. The showed experimental results endorse the adopted design approach confirming the optimality/validity of the manufactured solutions.