Modeling the Magnetic Behavior of N-Winding Components: Approaches for Unshackling Switching Superheroes

As designers strive to best take advantage of good switching devices and best grapple with the magnetic bottleneck, the solution often involves more complex magnetic structures. Modeling such structures with mathematics, necessary-and-sufficient circuit models, and physical circuit models is an essential element in understanding their complicated behavior. Our brief review has covered some of the primary modeling approaches, their advantages and disadvantages, and the translation between them. In addition, we introduced a necessary-and-sufficient circuit model with characterization advantages over the extended cantilever model. In a three-winding structure, the complete set of parameters can be obtained with only one-port impedance and two-port voltage ratio measurements, which can reliably be obtained to very high frequencies (compared to three of six parameters in the extended cantilever model). In a four-winding structure, the proposed model can find seven of 10 parameters in this way (compared to four of 10 for the extended cantilever model). This model may therefore be useful for a wide range of many winding magnetic structures, with a high ceiling on appropriate frequencies.