Title :
Power Transformers Internal Insulation Design Improvements Using Electric Field Analysis Through Finite-Element Methods
Author :
Khaligh, Alireza ; Vakilian, Mehdi
Author_Institution :
Illinois Inst. of Technol., Chicago
Abstract :
Understanding the potential and electric field distribution in the insulation system of a transformer during transients is vital to its construction. Therefore, we have developed a method for electric field analysis inside a power transformer. The method consists of the following steps. (1) A lumped parameter equivalent model is constructed by dividing transformer windings into several blocks. (2) The electric circuit parameters of this model are calculated. (3) Employing the results of the transformer transient model analysis as boundary conditions, a 2-D asymmetrical electric field finite-element analysis is performed to determine electric fields through the windings. The method has been examined employing power frequency and impulse voltages. We have also demonstrated successful application of the method to a transformer and have verified the computed results by comparison with measured results.
Keywords :
electric fields; finite element analysis; lumped parameter networks; power transformer insulation; transformer windings; 2-D asymmetrical analysis; electric circuit parameters; electric field analysis; electric field distribution; finite element methods; internal insulation; lumped parameter equivalent model; power transformers; transformer windings; transient model; Electric field; finite-element analysis; insulation design; power transformer;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2007.912771