Abstract
Turn-on change rate of drain current di DS(on)/dt is an electrical parameter suitable for online monitoring of junction temperature in SiC MOSFETs. In practical application, the change of the external circuit will change the temperature-sensitive characteristic of di DS(on)/dt. In this article, SiC MOSFET in Buck converter is taken as the research object. First, the influence of power loop inductance on diDS(on)/dt temperature sensitivity of SiC MOSFET is analyzed theoretically. Second, the relationship between the di DS(on)/dt of SiC MOSFET and the turn-off oscillation frequency of the drain-source voltage is established through the frequency spectrum of switching waveform with ringing. Based on theoretical and experimental studies, a method to modify the temperature-sensitive characteristic of di DS(on)/dt by turn-off oscillation frequency of drain-source voltage is proposed. The results show that the calibration method can largely eliminate the junction temperature monitoring error caused by the variation of the power loop inductance, and the maximum measurement error decreases from 100°C to 11.3°C after correction.
Original language | English |
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Journal | IEEE Transactions on Electron Devices |
Volume | 71 |
Issue number | 10 |
Pages (from-to) | 6208-6215 |
ISSN | 0018-9383 |
DOIs | |
Publication status | Published - 2024 |
Keywords
- Frequency spectrum
- SiC MOSFET
- Junction temperature monitoring
- Power loop inductance
- Temperature-sensitive characteristic