This paper presents a comprehensive investigation on the self-sustained oscillation of\nsilicon carbide (SiC) MOSFETs. At first, based on the double pulse switching test, it is identified\nthat the self-sustained oscillation of SiC MOSFETs can be triggered by two distinct test conditions.\nTo investigate the oscillatory criteria of the two types of self-sustained oscillation, a small-signal ac\nmodel is introduced to obtain the transfer function of the oscillatory system. The instability of the\noscillation is thereby determined by the two conjugate pole pairs of the transfer function. By analyzing\nthe damping ratios of the two pole pairs, the parametric sensitivity of various circuit and deviceâ??s\nparameters on the two types of self-sustained oscillation are obtained. The analyses reveal the\noscillatory criteria of the self-sustained oscillation for SiC MOSFETs. Based on the oscillatory criteria,\nnecessary methods are proposed to prevent the oscillation. The proposed oscillation suppression\nmethods are validated by the experiment at the end of the paper.
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