Title :
High-Frequency Modeling of Power Transformers for Use in Frequency Response Analysis (FRA)
Author :
Abeywickrama, Nilanga ; Serdyuk, Yuriy V. ; Gubanski, Stanislaw M.
Author_Institution :
Div. of High Voltage Eng., Chalmers Univ. of Technol., Gothenburg
Abstract :
This paper presents an advanced model of the frequency response of a three-phase power transformer for use in conjunction with diagnostic measurements by the method of frequency response analysis (FRA). The model includes high- frequency behavior of the laminated core and the insulation through taking into account the frequency dependencies of the complex permittivity of insulation materials (paper, pressboard, and oil) and of the anisotropic complex permeability of magnetic core and conductors. A lumped parameter circuit model is used to simulate the frequency response of open-circuit impedance, short-circuit impedance, and impedance between primary and secondary windings, in which the characteristics of circuit elements are calculated by means of the finite-element method. The effect of correct representation of each circuit element on the FRA response is analyzed and discussed in comparison to measurement results on a real transformer.
Keywords :
conductors (electric); finite element analysis; frequency response; power transformers; transformer cores; transformer insulation; transformer windings; FRA; conductor anisotropic complex permeability; finite-element method; frequency response analysis; insulation material complex permittivity; laminated core high- frequency behavior; lumped parameter circuit model; magnetic core anisotropic complex permeability; open-circuit impedance; power transformer high-frequency modeling; short-circuit impedance; Finite-element method; frequency response analysis; high-frequency modeling; power transformer diagnosis;
Journal_Title :
Power Delivery, IEEE Transactions on
DOI :
10.1109/TPWRD.2008.917896
