Development of Dynamic Magnetic Circuit Models Including Iron Saturation and Losses

Abstract

There is a continuing need in power electronic circuits to model magnetic components. It is necessary to determine the interaction of the magnetic component with the rest of the power electronic system so that a dynamic circuit model of the magnetic component including material saturation and iron losses is required. In addition, the magnetic component model must be valid when the magnetic component's excitation is not sinusoidal. A general dynamic magnetic circuit model is developed including specific magnetic saturation and iron losses, but the magnetic circuit model can be used with most other magnetic material models that include saturation and iron losses that have been proposed in the past. The dynamic magnetic circuit model is derived from Maxwell's equations along with useful theorems for building the circuit models from the structure of the magnetic device. Dynamic magnetic circuit models including magnetic saturation and iron losses are developed for selected magnetic components to illustrate the application of the modeling technique. The components include a simple inductor, simple transformer, a three winding center tapped transformer, and a three phase transformer.