Discharge Characteristics of Bubbles at Interface Between AIN Ceramic and FC-72 Liquid  

作　　者：Shenyang Mo Xuebao Li Zhibin Zhao Xiang Cui 

机构地区：[1]State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China

出　　处：《CSEE Journal of Power and Energy Systems》2024年第1期371-380,共10页中国电机工程学会电力与能源系统学报（英文）

基　　金：supported by the National Natural Science Foundation of China-State Grid Corporation Joint Fund for Smart Grid(No.U1766219)。

摘　　要：In order to evaluate the insulation of two-phase immersion cooling in the HV power electronic package,the insulation degradation of the dielectric interface induced by bubbles is investigated.In this paper,a test strategy with 50 Hz unipolar DC and AC combined voltage for partial discharge(PD)at boiling interface of AlN ceramic is proposed.The insulation threshold of an AlN ceramic surface is acquired in several dielectric environments,such as air,FC-72 liquid(FC-72,a Fluorinert^(TM) from 3^(TM)),FC-72 vapor,and boiling state of FC72.This reveals the deterioration of boiling on the insulation of the surface immersed in the dielectric refrigerant.To investigate the mechanism of the PD feature at the boiling interface,the PD patterns of the unrestricted bubble and the accumulated bubble are acquired and contrastively analyzed.Combined with the feature of the back discharge and the bubble behavior,the charged vapor-ceramic interface is relatively stable due to the accumulated vapor layer.This stability of the charged vaporceramic interface is broken if the bubble is unrestricted.Besides,it is discovered that the vapor-liquid interface inside the bubble may be another charged interface,which can also trigger a back discharge.

关 键 词：Biased AC voltage BUBBLE FC-72 partial discharge power electronic package surface discharge twophase cooling 

分 类 号：TM28[一般工业技术—材料科学与工程]