In this SBIR project, APEI, Inc. is proposing to develop a high efficiency, rad-hard 3.8 kW silicon carbide (SiC) Power Processing Unit (PPU) for Hall Effect thrusters. In Phase I of the project, APEI, Inc. will focus on investigating various circuit topologies, developing and applying performance metrics (i.e., optimizing magnetics, passives, frequencies, power density, efficiency, etc.), and developing a complete electric circuit design. By the conclusion of Phase I, APEI, Inc. will build and test a hardware "proof of concept" 1.3 kW power converter demonstrating the feasibility of the concepts proposed in this program. In Phase II of the project, APEI, Inc. will transition the "proof of concept" converter of Phase I into a higher power 3.8 kW interleaved system (paralleling three 1.3 kW converters), will modify the basic circuit design demonstrated in Phase I to include full control functionality and feedback / protection circuitry, and will integrate space qualified control and feedback components for a complete rad-hard system.