Performance Evaluation of Split Output Converters With SiC MOSFETs and SiC Schottky Diodes

Abstract

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/userguides/explore-bristol-research/ebr-terms/ This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see Abstract-The adoption of silicon carbide (SiC)MOSFETs and SiC Schottky diodes in power converters promises a further improvement of the attainable power density and system efficiency, while it is restricted by several issues caused by the ultra-fast switching, such as phase-leg shoot-through ('crosstalk' effect), high turn-on losses, electromagnetic interference (EMI), etc. This paper presents a split output converter which can overcome the limitations of the standard two-level voltage source converters when employing the fast-switching SiC devices. A mathematical model of the split output converter has been proposed to reveal how the split inductors can mitigate the crosstalk effect caused by the high switching speed. The improved switching performance (e.g. lower turn-on losses) and EMI benefit have been demonstrated experimentally. The current freewheeling problem, the current pulses and voltage spikes of the split inductors, and the disappeared synchronous rectification are explained in detail both experimentally and analytically. The results show that, the split output converter can have lower power device losses compared with the standard two-level converter at high switching frequencies. However, the extra losses in the split inductors may impair the efficiency of the split output converter, which is verified by experiments in the continuous operating mode. A 95.91% efficiency has been achieved by the split output converter at the switching frequency of 100kHz with suppressed crosstalk, lower turnon losses, and reduced EMI.Index Terms-Silicon carbide (SiC), split output converters, crosstalk, efficiency, electromagnetic interference (EMI).

Review of Packaging Schemes for Power Module

“…The switching frequency of Si IGBT-based converters is normally limited to 20 kHz, but the switching frequency of SiC MOSFETs can reach 100 kHz in a hard-switching converter [78]. With soft switching, the switching frequency can be even higher [79].…”

A DSOGI-FLL-Based Dead-Time Elimination PWM for Three-Phase Power Converters

“…However, the dead-time effect with the conventional pulse width modulation (PWM) is always an accompanied issue in the application of the converter, which can cause voltage losses, generate low-frequency (mainly 5 th and 7 th ) voltage/current harmonics, and reduce the dc-link voltage utilization [1]. The dead-time effect is especially serious in the low-speed motor drive system [2] and the high-switching frequency converter [3], [4], where large numbers of dead-time voltage errors are included in a fundamental period. Specifically, with nowadays developed wide-bandgap devices, the switching frequency of converters can reach up to 100kHz (with silicon carbide devices [4]), or even several MHz (with gallium nitride devices [5]).…”

“…The dead-time effect is especially serious in the low-speed motor drive system [2] and the high-switching frequency converter [3], [4], where large numbers of dead-time voltage errors are included in a fundamental period. Specifically, with nowadays developed wide-bandgap devices, the switching frequency of converters can reach up to 100kHz (with silicon carbide devices [4]), or even several MHz (with gallium nitride devices [5]). The dead-time effect will be further intensified with the ultra-high switching frequency and must be well addressed.…”

Research on Digital Synchronous Rectification for a High-Efficiency DC-DC Converter in an Auxiliary Power Supply System of Magnetic Levitation

“…Moreover, there are few studies on the DSR strategy in high-power applications. Therefore, it is necessary to further study the DSR strategy for the LLC DC-DC converter [26][27][28][29][30][31][32][33].…”

“…R s , R L , R Lm , R eqs , and R c are the parasitic resistance of the resonant tank and switches, which have negligible impacts on the FHA model and power transmission. C s is the parasitic capacitance of the primary switches, which can usually be ignored [27]. According to the analysis above, the equivalent cavity system and its transfer function can be calculated by Equation (14).…”