Finite-Element Simulation of Homogenised Field Models for Foil Windings

箔式绕组由于其高填充系数、低直流电阻和优越的热性能而在电能变换器中得到越来越多的应用。然而，它们具有特定的涡流效应，该涡流效应与朝向箔尖端的电流的单向重新分布有关，并且由于薄绝缘层而具有非常大的匝间电容。如今，只有三维有限元模型才能对这些效应进行足够精确的模拟，其中箔缠绕部件的所有几何细节都已解决。整体模型难以控制的尺寸阻碍了当代电工设计中箔式绕组的进一步改进。本研究项目的成果将是一个有限元箔绕组模型，它能够模拟涡流，电容和热效应箔绕组的计算成本是一个标准的线绕组。这一目标将通过分析和计算均匀化方法，一个专用的混合有限元，频谱元素离散化，误差控制网格自适应，场路耦合和多速率时间积分的适当组合来实现。所开发的数值方案的性能和可靠性将被证明为机器箔绕组，高频箔绕组Transformer和金属膜电容器。

Foil windings are increasingly applied in electrical energy converter because of their high fill factor, low DC resistance and advantageous thermal properties. They, however, feature a specific eddy-current effect related to the uni-directional redistribution of the currents towards the foil tips, and a comparably large interturn capacitance, related due to the thin insulation layers. Today, a sufficiently accurate simulation of these effects is only possible with three-dimensional finite-element models in which all geometric details in the foil-winding parts are resolved. The unmanageable size of the overall models impedes a further improvement of foil windings in contemporary electrotechnical designs. The outcome of this research project will be a finite-element foil-winding model which is capable of simulating eddy-current, capacitive and thermal effects in foil windings at a computational cost which is comparable to the one for standard wire windings. This goal will be achieved by an appropriate combination of analytical and computational homogenisation methods, a dedicated hybrid finite-element, spectral-element discretisation, error-controlled mesh adaptation, field-circuit coupling and multi-rate time integration. The performance and reliability of the developed numerical schemes will be demonstrated for machine foil windings, for a high-frequency foil-winding transformer and for a metallic film capacitor.