Demonstration of Efficiency Increase of 350 V-to-13.3 V Isolated DC-DC Converters for Electric Vehicles by Active Gate Driving

An active gate driving (AGD) is applied to a power converter product, and the efficiency increase of the power converter by AGD is demonstrated by measurements under switching noise aligned condition compared to a conventional gate driving. Specifically, the gate driver for a single Si power MOSFET comprising a 165 kHz, 350 V-to-13.3 V isolated DC-DC converter product for electric vehicles was replaced with a developed time-domain stop-and-go active gate driver, and the DC-DC converter efficiency and the spectrum amplitude at 27 MHz of the power MOSFET drain current of the conventional single-step gate driving and the proposed AGD are compared in measurements at 1.2 kW (= 13.3 V, 90 A) output. The results show that the proposed AGD reduces switching loss by 45% compared to the conventional single-step gate driving under the drain current spectrum amplitude alignment condition, resulting in a 10% reduction in total DC-DC converter loss and a 0.9% increase in DC-DC converter efficiency from 90.3% to 91.2%.