Experimental Verification of a Hybrid DC Breaker’s Solid-State Branch, Utilizing Discrete IGBTs, for LVDC Systems

Hybrid direct current (DC) breakers are essential for fast fault current interruption in low voltage direct current (LVDC) systems. This study investigates the current interruption capabilities of a hybrid DC breaker’s solid-state branch by using a programmable flyback power supply to generate different gate voltages. The results demonstrate that a single discrete insulated gate bipolar transistor (IGBT) in a TO-264 package can interrupt 1300 A by increasing the gate voltage from 16 V to 30 V, 12 times its rated value. By connecting four of these IGBTs in parallel with a symmetric layout, equal current sharing is achieved, allowing currents up to 4000 A to be successfully interrupted. These findings pave the way for small, efficient, cost-effective hybrid DC breakers that do not require expensive IGBT modules.