A loosely contactless transformer with a large air gap has small magnetizing inductance and large leakage inductance comparing with a closely conventional transformer. This paper focus on analysis, design and measurement results of the loosely winding contactless transformer using resonant converter. Finally, the experimental set up is built to transfer power of 300 W over the different gap var...

A method of modeling internal turn-to-earth and turn-toturn faults in distribution transformer is discussed in this paper. The models are entirely compatible with the Alternative Transients Program(ATP). The simulation of the faults is based on known leakage factors between the various coils of the transformer. These leakage factors are evaluated by using a simple method implemented in this pap...

Purpose – The power transformer is one of the most important pieces of equipment in a power system. The necessity for the optimum design of a power transformer arises because the design chosen should satisfy all the limitations and restrictions placed on it. This paper presents an improved fast evolutionary programming (IFEP) technique for the optimal design of a three-phase power transformer. ...

Original scientific paper Measurement of grid voltage harmonic components is an important part of power quality measurements. Current high voltage transformers with iron core are not linear and cannot easily be used for accurate measurement of "polluted" voltages in wide frequency range. In this paper, design details of a new coreless voltage transformer for power quality measurement are given....

A high voltage capacitor is relatively frequently switched during the periods of the system operations. The distribution transformers are subjected to many stresses during normal and abnormal operations. In this paper we simulate a portion of the distribution network of Durgapur Steel Plant using MATLAB 7.7 and observe the effects of capacitor switching events on transformer terminal at differe...

A two stage model is used to model the high frequency transient behavior of two winding transformers. The assumed transformer model’s parameters are estimated using the maximum likelihood estimation technique and the Kalman filter based on the time response data. Simulations are carried out using the frequency response data generated based on an assumed transformer model. The transfer function ...

The main goal of this paper is the determination of the effect of the metal oxide varistor (MOV) on various ferroresonance modes including fundamental resonance, subharmonic and chaos mode which are generated in electrical power systems. Chaos theory is used for analyzing this effect. Also, the bifurcation, phase plan diagram and time domain simulation are used for this purpose. The proposed po...

Since power transformer is a complex and critical component of the power transmission and distribution system, their reliability is crucially important for the energy system operation. So, there is an increasing interest in applying monitoring systems and on line diagnosis methods to transformers, as these are one of the most expensive and critical apparatus of a power system. Detecting failure...

There are some deficiencies in the improved three-ratio method even though it has been widely used in power transformer fault diagnosis. Using artificial neural networks, the power transformer fault diagnosis is improved in this article. With Matlab programming, three different kinds of neural networks, which are Radial Basis Function (RBF) neural network, Learning Vector Quantization (LVQ) neu...