Dynamic <i>dv/dt</i> Control Strategy of SiC MOSFET for Switching Loss Reduction in the Operational Power Range
Zebing Wu, Huaping Jiang, Zhenhong Zheng, Xiaowei Qi, Hua Mao, Li Liu, Li Ran
Abstract
For silicon carbide power <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s, high <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv/dt</i> in switching may bring about a high level of electromagnetic interference. This letter shows that the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> rate decreases at lower load currents. A dynamic <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> control strategy is then proposed for switching loss reduction in the whole operating range, by maintaining the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> at the maximum acceptable level. The effectiveness of the proposed control strategy is verified by an experiment, showing that the total switching loss can be reduced by as much as 22% at 30% load. Furthermore, the simulation shows that a power loss reduction of 11.4% can be obtained for an electric vehicle converter which typically operates at light loads for most of the time.