Integrated switch current sensor for shortcircuit protection and current control of 1.7-kV SiC MOSFET modules

This paper presents design and implementations of a switch current sensor based on Rogowski coils. The current sensor is designed to address the issue of using desaturation circuit to protect the SiC MOSFET during shortcircuit. Specifications are given to meet the application requirement for SiC MOSFETs. It is also designed for high accuracy and high bandwidth for converter current control. PCB-based winding and shielding layout is proposed to minimize the noises caused by the high dv/dt at switching. The coil on PCB are modeled by impedance measurement, thus the bandwidth of coil is calculated. At the end, various test results are demonstrated to validate the great performance of the switch current sensor.