A novel strategy is proposed for the coupling of field and circuit equations when modeling power devices in the low-frequency regime. The resulting systems of differential-algebraic equations have a particular geometric structure which explicitly encodes the energy storage, dissipation, and transfer mechanisms. This implies a power balance on the continuous level which can be preserved under appropriate discretization in space and time. The models and main results are presented in detail for linear constitutive models, but the extension to nonlinear elements and more general coupling mechanisms is possible. The theoretical findings are demonstrated by numerical results.

翻译：针对低频域电力器件建模中场与电路方程的耦合问题，本文提出一种新型策略。所得到的微分-代数方程组具有特殊的几何结构，可显式编码能量存储、耗散与传递机制。这种结构在连续层面隐含功率平衡关系，且可通过适当的时空离散化加以保持。本文详细阐述了线性本构模型的建模方法与主要结论，但该框架可扩展至非线性元件及更广义的耦合机制。数值算例验证了理论分析的正确性。