A Frequency-Based Stray Parameter Extraction Method Based on Oscillation in SiC MOSFET Dynamics

The dynamic switching procedure of an SiC device is highly related to the circuit stray parameters. Based on that fact, a specific extraction platform with SiC mosfet is presented as the extraction tool and works independently with the converter topology. The stray inductance for the arbitrary power flow path in the converter can be experimentally extracted. As only the voltage oscillation in SiC mosfet dynamics is measured, the uncertainty and errors in the previous time-domain methods caused by the probes synchronization, integral time zone selection, and voltage offset from a parasitic resistor get eliminated. Meanwhile, through the extension of the equivalent circuit equations, this method is also available in the stray capacitance extraction. Experimental results in the copper and laminated bus bars for the large-capacity converters validate the feasibility of the proposed method.