Wide Bandwidth Current Sensor for Characterization of High Current Power Semiconductor Modules

This paper presents a current sensor for commutation current measurement of high current power semiconductor modules with a bandwidth from DC up to 240 MHz. It is integrated in the commutation path with a coaxial housing generating a specified measurement point adding a low insertion inductance of 1.8 nH. It consists of tunnel-magnetoresistance sensors for low frequency current measurement and a PCB integrated Rogowski coil for high frequency current measurement. The measurement techniques are combined using the HOKA principle. The DC current linearity, the dynamic behavior as well as the signal-to-noise ratio of the current sensor is characterized.