Design and Performance Evaluation of a 200 deg C Interleaved Boost Converter (Preprint).

摘要

Recent advances in SiC power semiconductor technology and resulting availability of SiC Schottky rectifiers and controlled devices (BJTs, JFETs, and MOSFETs) make it possible to design and implement power converters capable of operating at 200oC. The design, prototype development, operation, and testing of a 74 kHz, 2 kW, 100 V/270 V inversely-coupled, interleaved, dc-dc boost converter over the 20oC to 200oC temperature range is presented in this paper. The advantages of coupled-inductor interleaved boost converters include increased efficiency, reduced size, reduced electromagnetic emission, faster transient response, and improved reliability. Optimization of a high temperature X-perm core based coupled inductor architecture, in terms of ac flux balancing and dc flux cancellation is discussed. DC characterization of SiC power devices used in the design (Schottky rectifier and JFET) over the 20oC to 200oC temperature range is presented as well. The power stage of the converter, including the power semiconductor devices, coupled inductor, and X7R ceramic input and output filter capacitors, was placed inside a temperature controlled chamber for testing. JFET gate drive circuit, input power source, and output load were external to the environmental chamber. Converter testing and performance evaluation was accomplished over a 20oC to 200oC ambient temperature range. As expected, JFET conduction loss increased and converter efficiency decreased with increasing temperatures. The drop in converter efficiency was in the range of 2-4% over the entire load (200W to 2 kW) and temperature (20oC to 200oC) ranges evaluated. At 200oC, output voltage ripple increased by approximately 60% due to the rapid decline in X7R capacitance at the high temperature extreme. The results obtained during this study suggest that the realization of 200oC power converters is feasible through a judicious selection of power semiconductor devices, magnetic core materials, and capacitor dielectrics.