Parasitic extraction is a powerful tool in the design process of electromechanical devices, specifically as part of workflows that check electromagnetic compatibility. A novel scheme to extract impedances from CAD device models, suitable for a finite element implementation, is derived from Maxwell’s equations in differential form. It provides a foundation for parasitic extraction across a broad frequency range and is able to handle inhomogeneous permittivities and permeabilities, making it more flexible than existing integral equation approaches. The approach allows for the automatic treatment of multi-port models of arbitrary conductor geometry without requiring any significant manual user interaction. This is achieved by computing a connecting source current density that supplies current to the model’s terminals, whatever their location in the model, subsequently using this current density to compute the electric field, and finally calculating the impedance via a scalar potential. A mandatory low-frequency stabilization scheme is outlined, ensuring a stable evaluation of the model at low frequencies as well. Two quasistatic approximations and the special case of perfect electric conductors are treated theoretically. The magnetoquasistatic approximation is validated against an analytical model in a numerical experiment. Moreover, the intrinsic capability of the method to treat inhomogeneous permittivities and permeabilities is demonstrated with a simple capacitor-coil model including dielectric insulation and magnetic core materials. Finally, the method’s practicality is exemplified with a common mode choke model in a comparison of simulated and measured results.

寄生提取是机电设备设计过程中的强大工具，特别是作为检查电磁兼容性的工作流程的一部分。一种从 CAD 设备模型中提取阻抗的新方案，适用于有限元实现，源自麦克斯韦方程的微分形式。它为宽频率范围内的寄生提取提供了基础，并且能够处理不均匀的介电常数和磁导率，使其比现有的积分方程方法更灵活。该方法允许自动处理任意导体几何形状的多端口模型，而无需任何重要的手动用户交互。这是通过计算为模型端子提供电流的连接源电流密度来实现的，无论它们在模型中的位置如何，随后使用该电流密度来计算电场，最后通过标量势计算阻抗。概述了强制性的低频稳定方案，以确保在低频下也能稳定评估模型。理论上处理了两个准静态近似和完美电导体的特殊情况。在数值实验中针对分析模型验证了磁准静态近似。此外，该方法处理不均匀介电常数和磁导率的内在能力通过一个简单的电容器线圈模型（包括介电绝缘和磁芯材料）来证明。最后，