Power devices based on wide-bandgap (WBG) material such as silicon-carbide (SiC) can operate at higher switching speeds, higher voltages and higher temperatures compared to those based on silicon (Si) material. This paper highlights some opportunities brought by SiC devices in existing and emerging applications in terms of efficiency and power density improvement. While the opportunities are clear, there are also design challenges that must be met in order to realize their full potential. For example, the fast switching speeds and high dv/dt of SiC devices can cause increased electromagnetic interference (EMI), current overshoot, cross-talk effect and have a negative impact on loads such as motors. This paper presents several potential solutions to tackle the application challenges and to fully exploit the superior characteristics of SiC devices and converters while attenuating their negative side-effects. This paper provides an overview of recent SiC device research and development activities based on academic literature, work carried out by the authors and collaborators as well as input from industry. It aims to provide benchmark results and a timely and useful reference to accelerate the adoption and deployment of SiC devices and converters.

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In this paper the effect of parasitic elements of the load connected to a power converter are considered. For the case of a high switching speed converter the equivalent parallel capacitance of the load or line inductance will cause a potentially large current overshoot, which will in turn lead to increased switching losses. This paper considers the relation between the operating conditions of the converter, such as switching speed, with the loss due to the parasitic elements. The inclusion of a small output filter inductor to reduce the switching loss and ringing is analyzed and a method for calculating suitable component values to reach a desired target performance is presented.

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In this paper the influence of silicon carbide (SiC) diodes on electromagnetic interference (EMI) generation in hardswitched power converters is investigated. The absence of reverse-recovery behaviour in these devices is expected to result in reduced EMI generation, in addition to significantly reducing switching losses. A simplified analytical model enabling the spectral envelope of the diode current waveform to be predicted is presented and numerical simulation is employed to validate this model. It is found that reverserecovery characteristics have greatest influence on the spectral content of the simulated diode current waveforms at frequencies above 10 MHz. Experimental measurements of switching current waveforms for both conventional Silicon (Si) diode and SiC diodes are presented and their frequency spectra are compared with the results of the numerical and analytical models.

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