A Fast Short-Circuit Protection Method for SiC MOSFET Based on Indirect Power Dissipation Level
Wenyuan Ouyang, Pengju Sun, Minghang Xie, Quanming Luo, Xiong Du
Abstract
This letter proposes an indirect power dissipation level short circuit protection (IPDL-SCP) method for silicon carbide (SiC) metal-oxide semiconductor field-effect transistors ( <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s). Due to differences between normal conducting and short-circuit (SC) conditions, this method is triggered by the voltage oscillation <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ss</sub> at the parasitic inductance ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ss</sub> ) of the source and directly monitoring <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</sub> of SiC <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> . For verification, the short circuit protection circuit is tested and proved functional on the SC test bench. Experimental results show that the protection circuit can respond to both hard switching fault (HSF) and fault under load (FUL), while the fastest response delays are 75 ns for HSF and 170 ns for FUL. Comparisons with other commonly used SC protection methods have also been made, which show that the proposed IPDL-SCP method has better performance in shorter protection delays.