Finite-Element Simulation of Homogenised Field Models for Foil Windings

• Applicants: Professor Dr.-Ing. Herbert De Gersem; Professor Dr. Sebastian Schöps
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
• Term: from 2020 to 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 436819664

• Final Report Year: 2023

Final Report Abstract

An increasing number of electric devices contains foil windings instead of wire windings because of their better electromagnetic and thermal properties, especially when operated at elevated frequencies. Foil windings suffer from a particular skin effect, which causes standard finite-element (FE) models to become unmanageably large. In this project, a homogenised foil-winding model was developed, which appropriately resolves the small-scale skin effects by a dedicated additional discretisation of the voltage distribution by globally supported polynomials. The method has been validated against an analytical solution for the continuum model. Moreover, a field-circuit coupling was designed to account for connected power-electronic equipment. A circuit-consistent improvement of the foil-winding model guarantees the stability of the model within time-stepping schemes. The homogenised foil-winding model has been extended to account for the capacitive effects between adjacent turns, which become relevant at higher frequencies. All methods have been implemented in the Python software package Pyrit and has been made publicly available. The foil-winding models have been tested for numerous technical examples.

Publications

• ‘Continuum models and analytical solutions for foil windings’. In: 27. Symposium on Electromagnetic Phenomena in Nonlinear Circuits (EPNC). conference contribution, June 2022
  J. Bundschuh; H. De Gersem & Y. Späck-Leigsnering
  
• ‘Foil-winding homogenization with polynomial shape functions with global support’. In: 19th International IGTE Symposium. conference contribution, Sept. 2022
  J. Bundschuh; Y. Späck-Leigsnering & H. De Gersem
  
• A modular Python-based finite element solver for multiphysics problems
  J. Bundschuh
  
• Pyrit: A finite element based field simulation software written in Python. COMPEL -The international journal for computation and mathematics in electrical and electronic engineering, 42(5), 1007-1020.
  Bundschuh, Jonas; Ruppert, M. Greta & Späck-Leigsnering, Yvonne
  
• ‘Analysis and stabilization of the foil conductor model’. In: 22nd European Conference on Mathematics for Industry (ECMI 2023). Ed. by K. Burnecki. conference contribution, European Consortium for Mathematics in Industry. 26th June 2023
  E. Paakkunainen; J. Bundschuh; I. Cortes Garcia; H. De Gersem & S. Schöps
  
• ‘Homogenization of foil windings with globally supported polynomials and including capacitive effects’. In: ENUMATH 2023. conference contribution, 4th Sept. 2023, p. 57
  J. Bundschuh; Y. Späck-Leigsnering & H. De Gersem
  
• A Stabilized Circuit-Consistent Foil Conductor Model. IEEE Access, 12, 1408-1417.
  Paakkunainen, Elias; Bundschuh, Jonas; Garcia, Idoia Cortes; De Gersem, Herbert & Schöps, Sebastian
  
• Homogenization of foil windings with globally supported polynomial shape functions. Archives of Electrical Engineering, 77-85.
  Bundschuh, Jonas; Späck-Leigsnering, Yvonne & De, Gersem Herbert