A Measurement Setup for Performance Evaluation of Power Converters based on Wide Bandgap Devices

Abstract

Modern power converters are more based on Wide Bandgap (WBG) semiconductors, such as Silicon Carbide Metal Oxide Semiconductor Field Effect Transistors (SiC MOSFETs). While SiC MOSFETs offer superior switching speeds and lower losses, their fast transients, in the order of tens of nanoseconds, pose significant challenges for accurate metrological characterization. This paper presents a flexible measurement setup designed for the performance evaluation of power electronic converters (AC to DC or DC to AC) based on WBG devices. The system integrates a bidirectional DC power stage and a regenerative four-quadrant AC grid emulator. A 12 bit oscilloscope, equipped with differential voltage probes and isolated current probes, is used for time domain and switching behaviour analysis, whereas an eight-channel wattmeter is used for efficiency measurement up to 150 kHz.As a first application, the system is used for the testing of a 25 kVA SiC-based three-phase inverter. Preliminary results of efficiency and distortion analyses, under various load conditions, are shown.