Recently, a variation of the conventional single-phase dual active bridge (DAB) topology has been
proposed, where an inductor-capacitor-inductor (LCL) resonant network tuned to the converter switching frequency is used as the AC coupling network. The approach reduces the reactive current
component that circulates between the converter bridges and thus reduces their VA rating. However it does not achieve zero voltage switching (ZVS) conditions at lower levels of power transfer. To address this question this paper uses frequency domain analysis to accurately predict the individual half-bridge ZVS boundaries for DAB converters with a resonant coupling inductance. The outcome is then used to modify the converter modulation strategy to extend the ZVS operating regions,
allowing ZVS to be maintained at lower power transfer conditions and for off-nominal primary-to-secondary dc-link voltage ratios. The theoretical ZVS boundary predictions are in precise agreement with results from switched simulations.
History
Start page
352
End page
357
Total pages
6
Outlet
Proceedings of the 2018 IEEE 27th International Symposium on Industrial Electronics (ISIE 2018)