An Ultrafast Universal Short-Circuit Protection Technique Based on Gate Current Detection for SiC MOSFET

Abstract

Fast and reliable protection against short-circuit (SC) faults is critically important for the reliable operation of power devices. In this letter, an ultrafast and universal short-circuit protection (SCP) method is proposed for Silicon Carbide (SiC) Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs), based on gate current detection. This method exploits the characteristic of the gate current to become negative during SC faults and constant positive during normal operation. The proposed gate current detection approach swiftly identifies faults during the SC process, ensuring rapid response time. Additionally, this method boasts broad applicability, being effective for both hard switching faults (HSFs) and faults under loads (FULs), and no extra auxiliary design is required for the three-pin device. The efficacy of the proposed SCP technique is validated through testing of the SCP circuit. Experimental results demonstrate that the proposed circuit is applicable to both HSFs and FULs, with response delays of 69 ns for HSFs and 50 ns for FULs, and total protection trigger time of 383 ns for HSFs and 352 ns for FULs.