COSS Losses in 600 V GaN Power Semiconductors in Soft-Switched, High- and Very-High-Frequency Power Converters
| Autor: | Kawin Surakitbovorn, Grayson Zulauf, Sanghyeon Park, Juan Rivas-Davila, Wei Liang |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Physics 020208 electrical & electronic engineering Gallium nitride 02 engineering and technology 01 natural sciences Capacitance Square (algebra) law.invention chemistry.chemical_compound Capacitor chemistry law 0103 physical sciences 0202 electrical engineering electronic engineering information engineering Power semiconductor device Cascode Electrical and Electronic Engineering Atomic physics Voltage Electronic circuit |
| Zdroj: | IEEE Transactions on Power Electronics. 33:10748-10763 |
| ISSN: | 1941-0107 0885-8993 |
| Popis: | We report losses from charging and discharging the parasitic output capacitor, ${\rm C}_{\rm OSS}$ , in Gallium Nitride (GaN) power devices with voltage ratings over 600 ${\rm V}_{\rm DS}$ . These losses are of particular importance in soft-switched circuits used at MHz switching frequencies, where the output capacitance of the device is charged and discharged once per switching cycle during the device's off-time. This process is assumed lossless. We measure ${\rm C}_{\rm OSS}$ losses from 5–35 MHz sine, square, and Class- $\Phi _{2}$ waveshapes in enhancement-mode and cascode devices, and find that losses are present in all tested devices, equal or greater than conduction losses at MHz frequencies, and exponentially increasing with $\mathbf{dV/dt}$ . The cascode device outperforms the e-mode devices under 300 V, but the e-mode devices are preferred above this operating voltage. Furthermore, we show that, within a device family, losses scale linearly with output energy storage. Packaging appears to have only a minor effect on these losses. Finally, we demonstrate 10 MHz, 200 W dc–dc converters with varying device configurations, showing that, even with constant circulating currents, moving to larger devices with lower ${\rm R}_{\rm DS,ON}$ actually degrades efficiency in certain applications due to ${\rm C}_{\rm OSS}$ losses. In the high-voltage, high-frequency range, these reported losses must be optimized simultaneously with conduction losses on a per-application basis. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|