Simulation And Design Of High Voltage And High Power SiC Solid State Power Controller

Multi-electric/all-electric aircraft is the trend of future aviation aircraft development,and its power level and intelligent requirements are also getting higher and higher.SiC solid-state power controller(SSPC)is the key module to realize high-power and intelligent power distribution of aviation aircraft..In this paper,a SiC SSPC is studied,and its electrothermal simulation method,inverse time overcurrent protection technology and hardware and software design techniques are studied.The packaging and degradation failure of SiC SSPC are analyzed based on failure physics.The main research contents of this paper are as follows:Firstly,the electrothermal modeling and simulation method of SiC SSPC is studied.The equivalent circuit modeling method of SiC MOSFET,the main device in SSPC,is studied.The MOS model,body diode model and parasitic parameter model of MOSFET are established.On this basis,the SSPC electrical simulation analysis method is established,and the SSPC electrical characteristic behavior model is established to analyze SSPC.Switching characteristics and load capacity;based on high power requirements,research SSPC thermal simulation analysis method,using thermal path method and finite element method,SSPC steady state and transient thermal simulation analysis,provide theoretical basis for SSPC thermal design.Secondly,the research on SSPC inverse time overcurrent protection technology is carried out.The inverse time-limited overcurrent protection curve and its key parameters are analyzed and analyzed.The inverse time-limited overcurrent protection modeling is established based on I~2t theory and thermal memory theory.On this basis,the expression discretization is implemented,and the inverse time-limited overcurrent protection algorithm is implemented by FPGA programming.The accuracy of the algorithm is verified by online simulation and experimental test.Then,the hardware and software design of SiC SSPC is carried out.According to the requirements of technical indicators,complete the overall scheme design of SiC SSPC;perform SSPC hardware circuit design,including drive circuit,short circuit protection circuit,condition monitoring circuit,etc.;perform SSPC software program design,including data processing program,AD acquisition processing program,visual upper position Machine and so on;and carry out the principle prototype construction and experimental test to verify whether its working characteristics meet the requirements.Finally,the failure and degradation of SiC SSPC power device package are analyzed.The failure mechanism of SiC SSPC bond wire package was studied,the key parts causing the failure of bond wire were determined,and the bonding wire process and layout optimization were carried out based on electrothermal simulation.The degradation failure mechanism of power device degradation was analyzed and multi-stress degradation was carried out.Experiment,establish a degradation model and complete life prediction.