Influence of Parasitic Parameters on Switching Characteristics in Single and Paralleled Silicon Carbide Power MOSFETs

This research evaluates the switching performance of silicon carbide (SiC) transistors compared to silicon (Si) transistors through a double pulse test. The performance was analyzed by measuring switching losses, di/dt, overshooting and switching times. The results demonstrated that switching losses, as well as rise and fall times, are reduced by half in SiC transistors. However, some overshoot in voltage and current waveforms was observed due to the high switching speed of SiC transistors. Subsequently, the impact of parasitic capacitive and inductive elements on the switching performance and switching losses in SiC transistors was studied across various values. The findings revealed that these parasitic components significantly affect the current balancing among SiC transistors in parallel driving circuits, with a recorded current difference of up to 6 A between transistors due to variations in internal capacitor values and the inductive effects resulting from current changes over time in the transistor's terminal paths. Simulation was conducted using LTspice software. In conclusion, the research results were summarized, and conclusions regarding the impact of internal elements on transistor performance were presented.