| Abstrakt: |
ABSTRACTThis paper quantifies the soft switching loss of a 1.2 kV SiCMOSFET module via a calorimetric method in a 78 kW full-bridge resonant inverter switched at approximately 200 kHz. By switching the SiCMOSFET just before the zero crossing of the current during turn-off and at perfect zero voltage during turn-on, this converter yielded an efficiency of roughly 99 %. Then, a simplified laboratory setup, including only a half-bridge series resonant inverter topology with split DC-link capacitors and an LC load, was built such that a real inverter operation was emulated, and thereby, turn-off loss was measured via an electrical method. A discrepancy of approximately 10 % is found between the two loss measurement methods, and the possible source for this difference is discussed. Furthermore, a standard double pulse test was also performed in an inductive clamped buck converter for measuring the hard switching loss. Finally, a comparison of losses obtained from the hard versus resonant topologies at the same load current was accomplished, which verifies the substantial benefits of the latter over the former. Thus, the merits of SiCMOSFETs for high frequency soft switched converters are demonstrated, which is the main contribution of this paper. |
