高压大功率弹性压接型IGBT器件封装绝缘结构中的电场瞬态特性  

Electric Field Transient Characteristics of High Voltage and High Power Compliant Press-Pack IGBT Device Package Insulation Structure

作　　者：刘思佳 文腾 李学宝 王亮 崔翔 Liu Sijia;Wen Teng;Li Xuebao;Wang Liang;Cui Xiang(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University ,Beijing 102206 China;China Electric Power Planning&Engineering Institute ,Beijing 100120 China;State Key Laboratory of Advanced Power Transmission Technology Beijing Institute of Smart Energy ,Beijing 100085 China)

机构地区：[1]新能源电力系统全国重点实验室(华北电力大学),北京102206 [2]电力规划设计总院,北京100120 [3]先进输电技术国家重点实验室(北京智慧能源研究院),北京100085

出　　处：《电工技术学报》2023年第23期6253-6265,共13页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金面上项目资助(52077073)。

摘　　要：压接型绝缘栅双极型晶体管(IGBT)是支撑柔性直流装备研制的核心器件,弹性压接型IGBT能更好地实现器件中各并联芯片的压力均衡,在电网应用场景中前景广阔。然而,器件内部的绝缘问题是高压器件研制过程中面临的主要挑战之一,因此,有必要在实际工况下分析器件绝缘结构中的瞬态电场分布,以指导绝缘设计。该文针对弹性压接型IGBT器件内部的复合绝缘结构,采用时域边界电场约束方程法,分别计算了单次关断工况和重复性导通关断工况下弹性压接型IGBT器件子模组封装绝缘结构中的瞬态电场分布。结果表明两种工况下,封装绝缘结构中最大电场强度均出现在芯片/聚酰亚胺(PI)钝化层界面上,且由于介质分界面两侧的绝缘材料介电常数和电导率参数不匹配,分界面上将会积累电荷。界面电荷密度随着时间逐渐增大,并影响电场分布,使得子模组中最大电场强度的模值和位置随时间发生变化。同时,单次关断工况下,最大电场强度的模值会更大。此外,该文提出通过改变器件中使用的绝缘材料,提高界面处的材料参数匹配程度,可以实现对子模组内电场分布的改善。该文所提方法能显著降低器件内部最大电场强度的模值,可为弹性压接型IGBT器件的封装绝缘结构设计和优化提供参考。With the development of flexible DC transmission technology,high-voltage and high-power IGBT(Insulated Gate Bipolar Transistor)has become an indispensable core component in DC power grid.Compliant press-pack IGBT has a wide application prospect in power grid because of its uniform pressure distribution and superior insulation performance.The calculation of the electric field distribution inside the device is an important step to improve its insulation performance.However,the transient electric field distribution under actual working conditions were not analyzed in previous studies.Therefore,the electric field distribution of the device under two working conditions is simulated,and a method to improve the matching degree of parameters between the insulating media is proposed in this paper,which can reduce the maximum electric field intensity in the device.Firstly,based on the actual working conditions of the device,the 2D finite element model is established,and the governing equations and boundary conditions of the submodule are determined.Secondly,by using the weighted residual method,the weak form of the governing equation is obtained,which is discretized in space and time.Then all nodes in the field are reordered,and the equation is decomposed into two to solve the transient potential and the normal component of the electric field intensity on the boundary respectively.Thirdly,the electric field distribution in the IGBT device is calculated under the conditions of single turn-off and repeatable turn-on and turn-off condition.Finally,a method of improving the matching degree of dielectric constant and electrical conductivity of the insulating material in the submodule is proposed to reduce the maximum electric field.The results show that the maximum electric field intensity in the submodule always appears at the interface of chip/PI passivation layer.Because the dielectric parameters of the insulating materials on both sides of this interface do not match,charges will accumulate.The interfacial charge affects th

关 键 词：弹性压接型IGBT 时域有限元法 电准静态场 单次关断工况 重复性导通关断工况 电场调控方法 

分 类 号：TM211[一般工业技术—材料科学与工程]