Magnetic material modelling using the PEEC method and linear basis functions

The PEEC method has been extensively used to model electromagnetic problems in power electronic systems. It is commonly used for modelling electrical parasitics (e.g. inductance) in busbars but less widely used to model magnetic components (e.g. transformers/inductors). Although an extension of PEEC method exists to include magnetic and dielectric materials, less is published on its use for modelling high permeability magnetic cores with small or no airgap. This case is extremely difficult to accurately model due to the increasing condition number of the magnetic coupling matrix. In this work we demonstrate the difficulty of applying standard PEEC method to typical high permeability magnetic cores and evaluate a modified PEEC method which partially overcomes this problem by increasing the order of the basis functions used to approximate magnetic fields within mesh cells.