Novel Figures of Merit for Evaluating the Performance of the Super-Cascode Switch

The super-cascode switch (SCS) has gained significant attention in the last decade due to its ability to achieve medium-voltage ratings using low-voltage semiconductors. However, there exists a notable absence of quantitative metrics to effectively evaluate the performance of the SCS. This gap exists because the behavior of the SCS is different from that of a traditional semiconductor switch, and traditional semiconductor performance metrics are not adequate for its evaluation. The present manuscript addresses this gap by introducing new figures of merit that are designed to evaluate the unique characteristics of the SCS. The practical value of these metrics is also demonstrated through a set of experimental studies. By applying these new figures of merit to one of the best-performing SCS configurations described previously in the literature, several opportunities for improvement are revealed. The SCS prototype described in this paper is evaluated experimentally at bus voltage levels up to 3.5 kV and current levels up to 200 A, demonstrating substantial performance improvements relative to the baseline configuration from the literature. These improvements are the result of iterative refinements to the balancing network, which are selected through a process that is informed by the application of the proposed figures of merit.