Improving approaches to the linearization of magnetic properties of electromechanical converter cores for numerical calculations
DOI:
https://doi.org/10.15588/1607-6761-2026-1-1Keywords:
piecewise linear approximation, magnetization curve, numerical calculations, core, electrical machineAbstract
Purpose. Improving the mathematical model for the linearization of magnetic properties of stator and rotor electrical steel based on the piecewise linear approximation of the magnetization curve, which will significantly reduce the number of nonlinear equations and substantially decrease the computational time for 2D and 3D circuit-field models of an asynchronous electromechanical converter while maintaining the accuracy of numerical calculations.
Methodology. Analytical methods for electromagnetic field calculation, the finite element method, analytical methods for electrical and magnetic circuit calculation, and piecewise linear approximation methods are utilized.
Findings. Mathematical models for linearizing the magnetization curve of stator and rotor electrical steel has been improved for both spatial 3D and plane-parallel 2D geometric models of the active part of AC electromechanical converters. An approach has been implemented to partition the general 2D geometric model of the stator and rotor core into n-elementary planes, applying a linear magnetization curve function at µr = const. Based on the 2D field modeling results of an electromechanical converters prototype in idle mode, compared to modeling results considering the full magnetization curve across the entire computational domain, the armature current residual does not exceed 2.654%. This allowed for a 4.89-fold reduction in the numerical calculation time for the 2D transient problem formulation using Comsol Multiphysics software.
Originality. The method for linearizing the magnetic properties of stator and rotor electrical steel in electromechanical converters has been improved, allowing for the application of a constant relative permeability value (µr =const.) to specific areas of the stator and rotor core computational domain while maintaining a sufficient level of numerical calculation accuracy.
Practical value. The proposed methodology for the linearization of the magnetization curve of stator and rotor electrical steel for spatial 3D and plane-parallel 2D geometric models of the active part of AC electromechanical converters can be applied to various types of electrical machines.
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Copyright (c) 2026 M.I. Kotsur, D.O. Danylchenko, A.V. Synetskyi
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