Abstract
SiC MOSFETs have an excellent characteristic of high switching speed, which can improve the efficiency and power density of converters significantly. However, the fast switching processes of SiC MOSFETs cause serious crosstalk problems in bridge-arm configurations, which restricts the devices’ performances. This paper presents a detailed and accurate improved crosstalk analytical model, which takes into account the nonlinear capacitances, the parasitic inductances, the reverse recovery characteristics of the anti-parallel diodes, and the nonlinear voltage switching and damping oscillation process. The novelty of the proposed model lies in the fact that under the condition of comprehensively considering all these non-ideal factors of the bridge-arm, the effects of multi-parasitic elements and multi-variables coupling to the crosstalk are hierarchically divided. The parasitic elements and their correlations are described in detail and the direct and indirect variables’ impacts are clearly traced. Thus, according to the different variables switching stages, the influence processes of these parasitic elements and variables can be integrated and a complete equivalent analytical model of the crosstalk process can be derived. The simulation and experiment platforms are established and a series of experimental verifications and comparisons prove that the model can replicate experimental measurements of crosstalk with good accuracy and detail.
Highlights
With the advantages of low switching loss, high block-voltage, high switching speed, and high thermal conductivity, SiC MOSFETs increasingly replace traditional silicon-basedMOSFETs in high frequency, high efficiency, and high power density applications [1,2,3,4].many kinds of converter topologies are designed based on the bridge-arm structure, the rapid change current and voltage seriously impact the parasitic elements and coupling affect the upper and lower devices, which interfere with the driver loop states and cause wrongly triggered
Many kinds of converter topologies are designed based on the bridge-arm structure, the rapid change current and voltage seriously impact the parasitic elements and coupling affect the upper and lower devices, which interfere with the driver loop states and cause wrongly triggered
In the case of SiC MOSFETs are employed in bridge-arm with high frequency, the high current and voltage switching rates significantly increase the amplitude of crosstalk [8]
Summary
With the advantages of low switching loss, high block-voltage, high switching speed, and high thermal conductivity, SiC MOSFETs increasingly replace traditional silicon-based. The current studies mainly focus on the coupling relationship between the crosstalk and the parasitic elements, while the analysis of the variable responses as the influence sources, caused by the bridge-arm switching processes, to the crosstalk is relatively simple. According to the switching processes of the bridge-arm, the correlation of the variables and parasitic elements with crosstalk in each stage are distinguished and the influence mechanisms behind these parameters are traced clearly On this basis, a detailed analytical model of crosstalk is established, the source impact variables and the critical parasitic elements are all considered and combined, their direct or indirect coupling effects to the crosstalk in different switching stages are clarified. The simulation calculations and experimental results are compared with the calculation results in [17,24], and the theoretical extremums, the results show that the proposed model can describe crosstalk response in more detail and accuracy
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
