Untitled in english

Author(s)

Nancy Mieko Abe

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 1997-12-22

Examining board members

Jose Roberto Cardoso; Edson Bim; Luiz Lebensztajn; Silvio Ikuyo Nabeta; Nelson Sadowski

• Advisor: Jose Roberto Cardoso

Abstract

This work presents a method for coupling the transient analysis FEM equations and the electric circuit equations. FEM applied for transient analysis of electromagnetic devices needs the excitation density currents. In practice, voltage sources supplies a large number of these devices and consequently a coupling method for simulating electric circuits and magnetic fields is required. Several methods have been developed to solve coupled electric circuits and 2D FEM electromagnetic models [1] [2], [3], [4], [5], [6], [7], [8]. The formulation developed by Dommel[9] and applied to EMTP (Electromagnetic Transient Programs) package to model transients in electric networks is used in the methodology presented in this work. Dommels approach replaces inductances and capacitances by na equivalent electric circuit using resistances and current sources.The transformed parameters regarding the formulation of FETD (Finite Element Time Domain) method are used to assemble the global matrix by modal analysis [10], [11], [12], [13]. Nodal analysis is a suitable method for coupling electric circuits and 2D FEM whereas the electrical parameters can be treated as one-dimensional finite elements. The resulting matrix equations presents a symmetric global matrix and can be solved by a step-by-step technique [14]. (AU)