Transformer two-dimensional silicon steel sheet magnetothermal coupling analysis method based on non-overlapping Mortar finite element method

Abstract

The invention discloses a transformer two-dimensional silicon steel sheet magnetothermal coupling analysis method based on a non-overlapping Mortar finite element method, and belongs to the technical field of transformer numerical calculation. Aiming at the limitations of large calculation amount and low precision when a traditional sharing method is used for processing a complex magnetic-thermal coupling problem of a transformer, the method adopts a finite element method to discretize equations by establishing a mathematical model of a magnetic field equation, a thermal field equation and a magnetic-thermal coupling relationship. A non-overlapping Mortar finite element method is used for carrying out region decomposition, a Mortar space and a test space are introduced to process sub-region interface continuity conditions, and an overall matrix equation is constructed through a Lagrange multiplier method. Meanwhile, an improved Mortar interpolation function is provided to improve the precision of an interface solution, and sub-region division is dynamically adjusted according to the distribution of a magnetic field and a thermal field by adopting a self-adaptive region decomposition strategy. During specific implementation, a geometric model is accurately constructed, material parameters are determined, finite element grids are reasonably divided, initial and boundary conditions are set, an alternating iteration method is used for solving, coupling of microcosmic and macroscopic scales is considered in combination with a multi-scale calculation method, and calculation efficiency is improved through parallel calculation optimization. According to the method, the problems of a traditional method are effectively solved, and a reliable basis can be provided for optimization design of the transformer.

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