Comprehensive Characterization of 10-kV Silicon Carbide Half-Bridge Modules

Abstract

This paper provides a comprehensive characterization of an example medium-voltage dc-based (MVDC) silicon carbide (SiC) MOSFET module of the type recently developed under Department of Defense (DoD) programs. As shown in this paper, these modules are capable of switching inductive loads very rapidly (<100 ns), with minimal overshoot and manageable parasitic-induced ringing. The transient analysis contained herein demonstrates a total per-cycle switching losses of 2.5 mJ at a bus voltage of 2 kV and a load current of 20 A. This figure is approximately two orders of magnitude lower than values recorded in the literature for commercially available silicon Insulated-Gate Bipolar Transistor modules with multikilovolt ratings at similar operating conditions (but which have lower blocking capability than the MVDC SiC module under study). These results corroborate the excellent switching performance of these MVDC SiC MOSFET modules, which has been only sparsely documented in the literature to date. In addition, this paper provides a comprehensive analysis of the static characteristics of these modules, including forward conduction, transfer characteristics, capacitance-voltage measurements, and quantization of parasitic impedances within the module housing. Technical challenges associated with making accurate and repeatable measurements with SiC modules of this scale are identified and explained, along with the details of the identified solutions. Finally, this paper includes a detailed description of the transient characterization test stand designed in support of this paper, which offers support for safely demonstrating the high-performance transient characteristics of MVDC SiC MOSFET modules at reasonable cost.