Measuring Current Transients in Power Electronics

With the increasing use of wide-bandgap (WBG) devices such as SiC and GaN, power electronics faces new measurement challenges due to significantly higher current and voltage slew rates. These fast switching transients place demanding requirements on current sensors and measurement systems. This session will discuss how the transfer function of the measurement system influences the captured time-domain current waveform. Different current sensing technologies will be compared, and key sensor requirements for high di/dt environments will be addressed. A particular emphasis will be placed on the characterisation of current shunts, especially M-Shunts using a network analyser and how their frequency-dependent behaviour affects measurement accuracy. Finally, the impact of shunt dynamics on switching loss determination in double-pulse testing will be examined, providing practical guidance for selecting and evaluating suitable measurement equipment