Research on High Frequency Current Measurement Method for the SiC MOSFET

Silicon carbide MOSFET can operate stably at high voltage level and high switching speed with lower switching power loss and has been widely used in electric vehicles and other fields. The measurement of current signal is very important in device protection and condition monitoring. With the increase of the current change rate in the transient process, traditional current measurement methods face more severe challenges. Based on the principle of double pulse test, the drain current of the SiC MOSFET is divided into different parts to calculate the equivalent frequency of transient current. Based on the double pulse test platform, the characteristics of coaxial resistance, Pearson coil, clamp current probe and Rogowski coil in high frequency current signal measurement are compared and analyzed from the Angle of bandwidth range and mechanical size. Finally, according to the actual application condition of the SiC MOSFET, the selection of current measurement method is proposed.