Design of a Single-Phase Common Mode and Differential Mode Inductor for Interleaved Converters

This paper analyses the design of single-phase interleaved inductors to provide inductance for differential mode (DM) circulating currents and common mode (CM) grid currents. The main design equations and a design optimization method are given. Comparison with other filter methods for equivalent performance shows reduced size with equivalent losses. Additional benefits using mixed core materials or due to phase shift in flux density are analyzed. Initial test results of a 120 kW converter demonstrate operation of the concept with a custom assembly that integrates the power electronics and coupled inductors in a combined heatsink.