Spice modeling and simulation of silicon-carbide power modules

Abstract

The design of power converters relies on computer modeling to accurately predict system electrical and thermal behavior prior to implementation. In the field of wide bandgap semiconductors, the extraordinarily high switching speed of silicon-carbide devices dictates that traditionally inconsequential parasitic elements can impact system level behavior. This is especially true for systems implementing multi-chip power modules. To ensure accurate simulations, a new and precise methodology for modeling these systems is needed. This thesis formulates a measurement based and empirically-validated methodology for modeling wide bandgap power modules. First, impedance analysis is used to create a parasitic model of the power module’s frequency domain behavior. Second, double pulse testing is implemented to characterize the dynamic behavior of the power module. Next, a SPICE model is developed from the frequency and time domain measurements. Finally, the model is validated through its accurate prediction of time domain waveforms and switching losses.