Numerical calculation of power transformers equivalent circuit parameters

Abstract

Numerical calculation of short connection current is a very important part of control, regulation and protection of the power supply system. Each important element of our system must be included in this calculation. An efficient algorithm for numerical calculation of elements of a power transformer equivalent circuit is described in this work. The finite element method was used for numerical calculation of nonlinear magnetic field. The energy method and method of mutual fluxes were used for calculation of the magnetic leakage flux. It is well known that the energy method, because of its simplicity and efficiency, is very often used for solving problems of this type. The mutual flux method has rarely been used because of its complexity and long duration of calculations. This work shows that the mutual flux method can be useful and successful for these calculations, by means of high-speed computers. The method for experimental determination of leakage flux was shown in this work, by means of the modern digital electronic measurement devices, as well. The results of this experiment were used to check the precision of numerical methods that have been used.