Transformers are the most critical and costly components in AC power systems. Insulation is weakest link transformers, design quality of a transformer's insulation system shall be confirmed by performingdielectric tests according to National or International standards. The impulse test more among dielectric tests, as it verifies integrity whole transformer. However, concluding result difficult ...

The low-frequency polarisation information of oil-paper insulation could be easily obscured by the conductance effect, and contained thus can not readily extracted from frequency domain spectroscopy (FDS). Given this issue, an alternative idea is reported to extract using logarithmic-derivative (LDS). present findings proved that parameters LDS applied for studying behaviour under moisture effe...

Since independence in India there has always been shortage of electricity and at no point of time we have been able to meet the peak demand. The gap between the demand and generation can be bridged/ minimized by either improving the installed capacity or reducing the consumer demand. The gap between availability & demand is of order 6% as on date. If we take into account the issues like environ...

This paper established a transient electric field model of high-voltage high-frequency (HVHF) transformer based on circuit-field coupling analysis. As the key component power electronic transformers (PETs), operating conditions HVHF are determined by converter circuit containing it. To find out electrical stress withstood solid insulation, it is essential to while considering converter. The and...

A Genetic Programming based Polynomial Networks Model (GPPNM) is presented in this paper to promote the diagnostic performance of incipient insulation fault of power transformers. Other than conventional hierarchical architecture to build polynomial networks, the proposed GPPNM constructs it using tree-like structure of Genetic Programming (GP). By means of flexible selection of low-order polyn...

In high voltage power cable system, partial discharge (PD) is a common phenomenon which reflects the degradation of insulation. When partial discharge happens inside the cable, leakage current will flow through the grounded conductor. To couple the partial discharge current, one feasible and effective method is placing a clamp-on high frequency current transformer around the grounded strap. In ...

The reliability of electrical energy networks depends on the quality and reliability of its electrical equipment, e.g. power transformers. Local failures inside their insulation may lead to catastrophic breakdowns and may cause high outage and penalty costs. To prevent these destroying events, power transformers can be tested on partial discharge (PD) activity before commissioning and monitored...