Coupling of Transient Fields, Circuits, and Motion Using Finite Element Analysis

Abstract

The transient analysis of a coupled electro-mechanical system is undertaken. The system consists partly of spatial regions, which may support magnetic fields, that are modelled by finite elements. The regions may be attached to external electrical sources and circuits, and may also be capable of rigid body motion with respect to one another. A method for coupling the electric circuit transient equations, transient magnetic field finite element equations, and the transient mechanical motion equations is described. Only the external source variation is assumed to be known; all other field, circuit, and mechanical motion quantities are treated as unknowns and calculated. Equations for transient analysis of a general, 2-dimensional, planar, non-linear, voltage-excited system are derived in detail. The Galerkin formulation, time-discretization, and linearization of these equations are presented. The resulting global system of coupled electro-mechanical equations is assembled and investigated. Included are examples of the application of the proposed method to perform transient analysis of practical coupled electro-mechanical systems.