The adoption of silicon carbide (SiC)\nMOSFETs and SiC Schottky diodes in power converters\npromises a further improvement of the attainable power\ndensity and system efficiency, while it is restricted by several\nissues caused by the ultra-fast switching, such as phase-leg\nshoot-through (ââ?¬Ë?crosstalkââ?¬â?¢ effect), high turn-on losses,\nelectromagnetic interference (EMI), etc. This paper\npresents a split output converter which can overcome the\nlimitations of the standard two-level voltage source\nconverters when employing the fast-switching SiC devices.\nA mathematical model of the split output converter has been\nproposed to reveal how the split inductors can mitigate the\ncrosstalk effect caused by the high switching speed. The\nimproved switching performance (e.g. lower turn-on losses)\nand EMI benefit have been demonstrated experimentally.\nThe current freewheeling problem, the current pulses and\nvoltage spikes of the split inductors, and the disappeared\nsynchronous rectification are explained in detail both\nexperimentally and analytically. The results show that, the\nsplit output converter can have lower power device losses\ncompared with the standard two-level converter at high\nswitching frequencies. However, the extra losses in the split\ninductors may impair the efficiency of the split output\nconverter, which is verified by experiments in the\ncontinuous operating mode. A 95.91% efficiency has been\nachieved by the split output converter at the switching\nfrequency of 100kHz with suppressed crosstalk, lower turnon\nlosses, and reduced EMI.\nIndex Termsââ?¬â?Silicon carbide (SiC), split output\nconverters, crosstalk, efficiency, electromagnetic\ninterference (EMI).\nI.
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