Modelling and loss simulation of magnetic components in power electronic circuit by impedance measurement

Losses in magnetic components occur in the core and in the winding. The loss estimation of winding losses in magnetic components is often based only on DC winding losses because it is hard to simulate the skin- and proximity effects in simple simulation components. For the core losses the Steinmetz equation, which is based on sinusoidal current waveforms, is often used. This paper presents a new approach to impedance measurement with subsequent modeling into electrical networks for use in Spice-based circuit simulators. For simulation, the measuring of the frequency-dependent behavior of the passive components through an impedance analyzer is needed. It is necessary to model a circuit with a frequency-depended resistor on the basis of the passive component measurement. The values of the components in the circuit can be fitted and optimized using a Matlab algorithm. The fitted circuit can then be implemented into an existing Spice-model via a current-dependent current-source. This source avoids affects on the switching behavior from the loss simulation network. The proximity and skin-losses can be simulated with sufficient accuracy. Core losses cannot be considered due to the nature of the measurement, but they can be included by evaluation of the edge steepness together with the Steinmetz equation.