Metal oxide surge arresters (ZNO) are used widely in power system to protect equipments from over voltages. Non uniform potential distribution leads to the depressed service life and low safe reliability, so grading ring is applied on HV surge arrester order to uniform the electric field distribution. One of the problems of arresters is leakage current in power frequency that different paramet...

As far as the design of SPDs is concerned, the need exists for simplifying its circuit structure in fulfilment of the prerequisite condition of protective reliability. The circuit simplification for SPDs is of benefit to lower the cost of manufacture and reduce the size of chassis. Considering that the traditional SPD that has been extensively used on single-phase AC power supply lines requires...

We analyze data from two FAST satellite passes in the vicinity of auroral surges (as seen in the VIS auroral imager on the Polar satellite) to study the large scale ionospheric electrodynamics of the surge, focusing in particular on the configuration of field-aligned and ionospheric currents. While most previous ground and satellite observations have found the surge to be a region of predominan...

This paper investigates the influence of voltage dips on large electric driven gas compressors (EDC) considering a typical application in the oil and gas industry. Voltage or power dips are electric disturbances encountered in EDC which are mainly caused by faults in the electrical grid and might last for durations up to 150ms. For gas compression applications, the loss of driver torque often p...

surge and rotating stall phenomena are two dynamic instabilities that occur in both axial and centrifugal compressors. surge is the stream instability phenomenon in compressor that imposes severe damages to the compressors. nowadays, suppressing surge phenomenon is one of the most important issues in oil and gas industries, especially when flow reduction or gas reflux is considered. this resear...

3. Explain the necessity for generating impulse currents and mention the features of impulse current generators. Impulse current generation is required for, o Testing of surge diverters o Testing of non-linear resistors o Electric arc studies o Studies of electric plasmas in high current discharges  For producing impulse currents of large value, a bank of capacitors connected in parallel are c...

Artificial neural networks (ANNs) are addressed in order to estimate the electric field across medium voltage surge arresters, information which is very useful for diagnostic tests and design procedures. Actual input and output data collected from hundreds of measurements carried out in the High Voltage Laboratory of the National Technical University of Athens (NTUA) are used in the training, v...

Transient voltage surge suppressors are characterized from the point of view of electric utilities wishing to ofler to their customers a comprehensive surgeprotection plan. This plan involves a surge arrester installed at the service enlrme and one or more plug-in suppressors installed within Me premises, at the point of connection of a surge-sensitive appliance. Complementary tests were conduc...

The current surge of interest in multiferroic materials demands specialized measurement techniques to support multiferroics research. In this review article we detail well-established measurement techniques of the magneto-electric coupling coefficient in multiferroic materials, together with newly proposed ones. This work is intended to serve as a reference document for anyone willing to develo...