Abstract
It is commonly assumed that power semiconductor switching losses are the same for high-side and low-side devices in a half-bridge power module. However, this article reveals that the high-side SiC mosfet in a medium-voltage power module exhibits over 40% higher switching energy compared with the low-side SiC mosfet. The loss imbalance is attributed to the parasitic high-side gate capacitance in the power module, which contributes to the equivalent high-side Miller capacitance. A physics-based switching energy dissipation model is, therefore, proposed, distinguishing between low-side and high-side switching energy dissipation. Double pulse testing demonstrates that high-side switching energy dissipation increases by 5 mJ per 2.5-pF increment in the equivalent Miller capacitance, aligning closely with the analytically calculated increase of 6 mJ per 2.5 pF. Continuous power module testing shows a 10 °C increase in high-side junction temperature. The findings from this article offer crucial insights into research, design, and manufacturing of half-bridge modules enabled by SiC MOSFETs.
Original language | English |
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Journal | I E E E Transactions on Power Electronics |
Volume | 39 |
Issue number | 5 |
Pages (from-to) | 5806-5819 |
Number of pages | 14 |
ISSN | 0885-8993 |
DOIs | |
Publication status | Accepted/In press - 2024 |
Keywords
- Capacitance
- Capacitive couplings
- Couplings
- Double pulse testing
- Half-bridge switching dynamics
- MOSFET
- Medium voltage SiC MOSFETs
- Miller capacitance
- Multichip modules
- Power module modelling
- Silicon carbide
- Switches
- Switching loss
- Switching losses