Modeling Controlled Switches and Diodes for Electro-Thermal Simulation

Designers of advanced power converters may choose from a variety of switching device models for simulation. Some situations call for simple idealized models, while others require physics-based models. When evaluating thermal system performance, a behavioral model that includes both conduction and switching losses is desired. A set of models has been developed to include both unidirectional devices, such as IGBTs, BJTs, and diodes, and bidirectional devices, such as MOSFETs. Logic and timing elements are used to insert voltage and current sources into the circuit at appropriate times. All losses affect circuit operation, so simulation can accurately predict losses when the load affects the switching pattern. The model was constructed in Dymola and included thermal ports to be attached to a model of the thermal system. Temperature dependency of device parameters can be included with minor modifications. Experimental verification is shown