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Wide Bandgap devices are becoming more popular because of their higher switching performance. However, this higher performance comes at the cost of increased susceptibility to parasitic effects and leads to problems such as voltage overshoot and ringing of the switching node. Many strategies have been described in the literature that suppress these undesirable effects and enable faster switching. Generally, the literature describes the effectiveness of a new suppression method by experimentally comparing the outcomes when the strategy is used versus when it is not used. However there is no study that compares experimental results of the many different reported strategies with each other. This work is a meta-analysis of previously reported experimental results of WBG devices that compare the different reported strategies against one another. This shows which class of strategy holds the most promise for future development. The data presented also enables future strategies to be benchmarked against the current state-of-the-art.

Recent advances in semiconductor technology have paved the way for ultra-fast switching capabilities. This increase in switching speed enhances efficiency, power density, and frequency but also increases overvoltage oscillations at the switching node. Existing methods that effectively suppress this overvoltage include slower switching and minimisation of inductance, but unfortunately, these methods become very difficult to implement as the switching speed increases. A new oscillation suppression method, Zero Overvoltage Switching (ZOS), has previously been developed in which the overvoltage is suppressed very effectively by increasing both the switching speed and inductance, contrary to mainstream expectation. This is the only oscillation suppression method that becomes more effective as the switching speed increases and is not constrained by the minimisation of inductance, yet this method has not gained widespread recognition. This is expected because Zero Overvoltage Switching is not explained within the context of existing knowledge, and the argument for implementing it is difficult in the very narrow window where the advantages outweigh the effort. This research develops a generalised fundamental model to better understand Zero Overvoltage Switching by describing the mechanics of fast and slow switching events. The model is also able to provide insights that lead to methods to apply Zero Overvoltage Switching over a broader range of voltages and currents.