The impact of exponentially decaying direct component on the Fourier algorithm is theoretically investigated first in this paper. A new algorithm to eliminate the error caused by this decaying component in the Fourier algorithm has been proposed. Furthermore, three simplified methods are proposed to alleviate the computation burden. The performance of the Fourier algorithm improved with these m...

Second harmonic restraint is still commonly used to discriminate fault current and transformer inrush conditions. Such approach, however, has some disadvantages and limitations. Therefore various other criteria signals for power transformer inrush discrimination have been analysed. The paper presents a new multi-criteria stabilization algorithm that employs fuzzy reasoning technique for better ...

This paper presents guidelines for the accurate evaluation of harmonics and flicker generated by ac electric arc furnaces, and its propagation through transmission and distribution systems. It is presented a typical case where a HV system supplies a high capacity arc furnace. The electrical network is simulated using the ATP version of the EMTP where a non-linear time-varying three-phase arc mo...

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...