Characterization of Nonlinear Field-Dependent Conductivity Layer Coupled With Protruding Substrate to Address High Electric Field Issue Within High-Voltage High-Density Wide Bandgap Power Modules
Characterization of Nonlinear Field-Dependent Conductivity Layer Coupled With Protruding Substrate to Address High Electric Field Issue Within High-Voltage High-Density Wide Bandgap Power Modules
复制标题
与突出基板耦合的非线性场相关导电层的表征，以解决高压高密度宽带隙功率模块内的高电场问题
DOI：
10.1109/jestpe.2019.2953145
复制
发表时间：
2020
影响因子：
5.5
通讯作者：
M. Ghassemi
中科院分区：
文献类型：
--
作者：
M. Tousi;M. Ghassemi
除了宽禁带(WBG)电源模块的阻挡电压较高外，它们的体积目标是比硅基模块的体积小几倍。这转化为模块内更高的电应力，进而导致不可接受的局部放电(PD)活动的更高风险，从而导致陶瓷基板和硅胶的老化和退化。由于电源模块几何尺寸较小，在mm-或$\MU\Text{m}$(用于凸起)-范围内，并且由于其电场几何形状极其不均匀，传统的高压测试电极几何形状不能模拟真实条件。另一方面，以大学为基地的实验室往往不能提供用于测试样品和高质量材料的制造/工厂条件。因此，很难通过实验来确定电场控制方法的有效性。在这种情况下，电场数值计算是评估不同电气绝缘设计的唯一可行方法。为此，在COMSOL多物理中建立了用于WBG电源模块的电气绝缘系统的有限元模型。结果表明，目前的几何技术不能单独解决高密度WBG模块内的高电场问题。为了解决这个问题，首次提出了将非线性场变导电性(FDC)材料应用于高电应力区域，并结合最近引入的一种称为凸起衬底的几何技术。在这方面，对非线性FDC层进行了表征，并对各种降低电场的设计进行了评价。此外，还将研究工作频率对上述方案性能的影响。
In addition to higher blocking voltages of wide bandgap (WBG) power modules, their volume has been targeted to be several times smaller than that of Si-based modules. This translates into higher electric stress within the module and, in turn, a higher risk for unacceptable partial discharge (PD) activities, leading to aging and degradation of both the ceramic substrate and the silicone gel. Due to the small dimensions of power module geometry, in the mm- or $\mu \text{m}$ (for protrusions)-range, and due to its extremely non-uniform electric field geometry, conventional high-voltage testing electrode geometries cannot simulate real conditions. On the other hand, university-based laboratories often cannot provide manufacturing/factory conditions for testing samples and for high-quality materials. Thus, it is difficult to determine the efficacy of electric field control methods through experiments. In these situations, numerical electric field calculation is the only feasible way to evaluate different electrical insulation designs. To this end, the finite-element method (FEM) models of the electrical insulation system used in WBG power modules are developed in COMSOL Multiphysics. It is shown that the current geometrical techniques alone cannot address the high-electric field issue within high-density WBG modules. To address this issue, for the first time, nonlinear field-dependent conductivity (FDC) materials applied to high-electric stress regions in combination with a recently introduced geometrical technique known as the protruding substrate is proposed. In this regard, the nonlinear FDC layer is characterized and various designs to reduce the electric field are evaluated. Moreover, the effect of the operating frequency on the performance of the solution mentioned above will be studied.
DOI：
10.1109/tdei.2010.5539704
发表时间：
2010-08
影响因子：
3.1
作者：
Ningyan Wang;I. Cotton;J. Robertson;S. Follmann;K. Evans;D. Newcombe
通讯作者：
Ningyan Wang;I. Cotton;J. Robertson;S. Follmann;K. Evans;D. Newcombe