电工技术学报2025,Vol.40Issue(16):5068-5080,13.DOI:10.19595/j.cnki.1000-6753.tces.241233
基于驱动电压主动切换的Si/SiC混合器件结温波动平滑控制
Smooth Control For Junction Temperature Fluctuation of Si/SiC Hybrid Switch Based on Active Switching of Drive Voltage
摘要
Abstract
The Si/SiC hybrid switch has low cost and low loss advantages for supporting the development of large capacity and high reliability of power electronic equipment.The change of load current causes a significant fluctuation of the junction temperature of SiC MOSFET,and then the improvement of the overall life of the Si/SiC hybrid switch is restricted.Therefore,this paper proposes a smooth control strategy for junction temperature fluctuation based on active switching of drive voltage.The junction temperature fluctuation of the SiC MOSFET in the Si/SiC hybrid switch is significantly smoothed.The difference in junction temperature fluctuation between the SiC MOSFET and Si IGBT is also reduced,and the remaining service life of the whole hybrid switch is effectively extended. Firstly,the influence of drive voltage on the switching trajectory of the hybrid switch is analyzed.The loss model of the hybrid switch,considering the influence of drive voltage,is established.Secondly,based on the loss distribution of the hybrid switch under different drive voltage combinations,four drive voltage modes are determined to correspond to the four load intervals divided by the equal rated current.Combined with the designed drive voltage autonomous switching circuit,a complete set of the Si/SiC hybrid switch thermal management schemes is formed.Finally,the designed drive circuit board is mounted on a single-phase inverter.The drive voltage switching function of the drive circuit board and the effect of the proposed strategy on the junction temperature swing suppression are verified. Based on the experimental platform,when the inverter runs under the load profile set,four drive voltage modes are output accurately by the designed drive voltage switching circuit according to the effective value of the load,and the sinusoidal AC current can be stably output by the single-phase inverter in each drive voltage mode.Through the proposed strategy,under any load fluctuation,the smoothness of the junction temperature fluctuation of MOSFET is more than 30%,and the difference in junction temperature fluctuation between MOSFET and IGBT is reduced by more than 49%. The following conclusions can be drawn.(1)The drive voltage affects the current trajectory,voltage trajectory,and steady-state shunt between MOSFET and IGBT during the turn-on process of the hybrid switch.The drive voltage has multiple degrees of freedom to control the loss of the hybrid switch.(2)In the Si/SiC hybrid switch,the junction temperature of MOSFET is greatly affected by the drive voltage regulation,but the junction temperature of IGBT is less affected.(3)Through the switching of four drive voltage modes in load current intervals of VGM=15 V,VGT=15 V;VGM=20 V,VGT=15 V;VGM=20 V,VGT=20 V;VGM=15 V,VGT=20 V,the loss of MOSFET can be reduced under heavy load conditions to reduce the junction temperature and increased under light load conditions to increase the junction temperature.(4)Through the proposed strategy,the junction temperature fluctuation of MOSFET can be smoothed by more than 30%under any load fluctuation,and the junction temperature fluctuation's amplitude difference between MOSFET and IGBT is reduced by up to 84.4%.The service life of the Si/SiC hybrid switch is extended.关键词
Si/SiC混合器件/SiC MOSFET/结温波动平滑/驱动电压模式/负载波动Key words
Si/SiC hybrid switch/SiC MOSFET/smoothing of junction temperature fluctuation/drive voltage mode/fluctuation of load分类
信息技术与安全科学引用本文复制引用
白丹,涂春鸣,龙柳,肖凡,肖标..基于驱动电压主动切换的Si/SiC混合器件结温波动平滑控制[J].电工技术学报,2025,40(16):5068-5080,13.基金项目
国家自然科学基金资助项目(52130704). (52130704)