Transient phenomena in power transformers theoretical and practical approach
In recent decades the theoretical and experimental study of transient phenomena regarding power transformers has experienced a great development. Results of these studies allowed the elucidation of the main theoretical and practical aspects of the transient phenomena due to propagation of impulse voltages inside the transformers. These studies increased the safe operation of power transformer and led to the introduction of rational insulation usage and also helped to develop efficient protection measures.
Calculation methods for lightning impulse voltage distribution in power transformers
This paper aims to develop and update the methodology for calculating the stress to which the internal insulation of power transformer is subjected during lightning impulse test. Power transformer internal isolation consists of insolating intervals of oil impregnated paper, transformer board and oil. In whole, the transformer's insulation must withstand the voltage testing levels prescribed by the standards. One of the methods for determining the internal stress of various parts of the power transformer's insulation is by using mathematical models.
Determination of Impulse Stresses within Transformer Windings by Computers [includes discussion]
A theoretical basis for determination of the short-time transient characteristics of transformer windings is presented. This theory was used to develop an accurate, economical, and convenient method of determining impulse voltage stresses within transformer windings through the use of modern digital and analogue computers. The method has been developed for and applied to the shell form of construction, but the theory is equally applicable to other forms of construction.