Design of a 1200 kV power transformer is a real challenge for designer from dielectric point of view. It is possible to design a more compact transformer meeting even higher insulation levels with lesser insulation content. This has been possible with the introduction of sophisticated Computer-Aided Electrostatic Field Analysis. Analysis of the Lead Exit assembly of 1200 kV HV is presented. Two...

This paper describes an accelerated ageing experiment of transformer oil/paper insulation with preset moisture levels. These samples were tested with return voltage and polarisation/depolarisation measurements. Molecular weight has also been measured with Gel Permeation Chromatography (GPC). Results suggested the impact of moisture on the ageing of oil/paper insulation. An attempt has been made...

The insulation of the high voltage equipment is deteriorated due to the partial discharges (PDs). So it is required to monitor PDs continuously for prediction of insulation life, replacement time and early indication of outages of HV power equipment. In this work, an optical network is used to detect and measure the PDs in a model transformer.

In this paper, a Markov maintenance model for predicting the remaining life of transformer insulation has been developed. It incorporates various stages of insulation deterioration and minor maintenance state. Given that a current state of insulation ageing has been reached, from a diagnostic testing and inspection, this model is capable of computing the predicted average time before insulation...

Partial discharge inside a transformer is mainly responsible for the insulation aging and damage of the transformer. However, partial discharge is usually accompanied by external signals like sound, light and electrical signals and detectable physical phenomena such as characteristical gas and dielectric loss. Therefore, it is of great significance to monitor online the external signals and phe...

In this paper, a model predictive framework is used to optimize the operation and maintenance actions of power system equipment based on the predicted health sate of this equipment. In particular, this framework is used to predict the health state of transformers based on their usage. The health state of a transformer is hereby given by the hot-spot temperature of the paper insulation of the tr...

This paper deals with three types of power transformer failure analysis tests which can help in monitoring the transformer condition. The three methods are Conventional oil test, Furan derivatives test and Markov models criteria. Conventional oil testing procedure includes determination of gas concentrations in the transformer oil sample and analyzing the fault by considering ratio of two suita...

Development of the power grid towards a more reliable and smarter system requires frequent on-line monitoring of the power components. Power transformers and their bushings are particularly important components in a power transmission system and their insulation degradation may lead to catastrophic failures. Time consuming and costly replacement of these components raise the importance of their...

Abstract. Japan Atomic Energy Agency as the JApan Domestic Agency (JADA) for ITER and the Domestic Agency of EU (EUDA) agreed the procurement sharing for the ITER NBI power supply system. The JADA contributes procurement of dc -1 MV ultra-high voltage (UHV) components such as a -1 MV dc generator, a transmission line and a -1 MV insulating transformer. The dc UHV insulation has been carefully a...