IEEE Workshop on Wide Bandgap Power Devices and Applications in Asia (WiPDA Asia 2018)

242 / 2017-11-22 16:25:02

Damping Current Oscillation of SiC JFET Bi-directional Switches during Turn-on Transient

SiC JFET,Bi-directional Switches,Current Oscillation,equivalent circuit model,snubber capacitor

Plenary track > Hard-switched and soft-switched applications

Current oscillation of Silicon Carbide (SiC) based Junction Field-Effect Transistor (JFET) Bi-Directional Switches (BDSs) during turn-on transient has an impact on the stability and reliability of power electronic conversion systems. Proper handling of the current oscillation during turn-on transient is suitable to exploit the full potential of fast SiC JFET BDSs. In this paper one method is proposed to damp the current oscillation, namely, paralleling a snubber capacitor (CJ) with JFET in power loop. Equivalent and simplified circuit models considering all parasitic elements for SiC JFET BDSs for the turn-on condition are presented. Simple analytic expression is introduced to provide the theoretical analysis of the switching oscillation phenomenon, and to guide the optimal value of snubber capacitor. Experimental results validate the effectiveness of the proposed method.