Energy technique procedure for computing the leakage reactance in transformers is presented. This method is very efficient compared with the use of flux element and image technique and is also remarkably accurate. Examples of calculated leakage inductances and the short circuit impedance are given for illustration. For validation, the results are compared with the results obtained using practic...

This paper investigates protection integrity of distribution transformers in Ghana. The purpose of the study was to find the main causes of distribution transformer failures in Ghana. The study was conducted in the Ashanti East Region, one of the operational areas of Electricity Company of Ghana ECG with high incidence of distribution transformer burnouts. Data on status of protection systems o...

Transformers are normally designed and built for use at rated frequency and perfect sinusoidal load current. A non-linear load on a transformer leads to harmonic power losses which cause increased operational costs and additional heating in power system components. It leads to higher losses, early fatigue of insulation, premature failure and reduction of the useful life of the transformer. To p...

With increasing competition in the global market continuous research are done to optimize the behavior of materials to be used in transformer. Since silicon (Si) comprises a very good crystallographic arrangement then that of iron (Fe), silicon is fused with iron for considerable reduction of leakage flux in it. A novel M19 high grade silicon steel core has been introduced for 1 KVA 415/230V de...

In many text books and papers such as [1]-[5], it is possible to find descriptions about shunt fault calculations and about the influence of the three-phase transformer connection Dyn on the fault currents distribution through distribution transformers. In [6] is described a method for digitally simulating a three-phase power system which is subjected to a fault at one location with blown fuse ...

This paper addresses the optimum transformer design problem to minimize the active part cost of three phase core type distribution transformer. The transformer design process involves substantial heuristic exercise to select the design, best suited to a set of specifications. The design problem considers minimization of total cost of core and conducting material, while constraints are imposed o...

in order to reduce the volume and size of distribution power transformer, precise and extended controlling of transformer output, the conventional transformers are replaced by intelligent universal transformers (iuts). in this paper, an iut, typical of iran national grid, with the voltage ratio of 20kv:380 v is designed and simulated. regarding the iut implementation, a cascaded h-bridge invert...

This project presents reactive power compensation in a distribution power system. DSTATCOM (distribution static compensator) is a reactive power compensator for power quality improvement in a three phase four wire distribution system. A voltage source converter (VSC) based DSTATCOM with a zig-zag transformer is used for the compensation of reactive power for voltage regulation along with load b...

To study the voltage distribution in transformer windings under VFTO, a model for transformer windings has been developed based on Multi-conductor Transmission-Lines (MTLs) theory and the computing equations of the model based on FiniteDifference Time-Domain method (FDTD) is deduced. The Vector Fitting method is adopted to treat the frequency-dependent parameter by expanding the time-domain for...

Copper and aluminium are the two conductors most commonly used in transformer windings. This study presents a comprehensive comparison of distribution transformers built either with copper or with aluminium windings. The comparison is based on winding material conductivity, density, cost, connectivity, oxidation, machinability and behaviour under short-circuit. Additionally, a parametric analys...