Analysis of international competitiveness of Slovenia, Croatia, Serbia, Macedonia, BiH and Montenegro.
COBISS.SI-ID: 1618574
The calculation of flicker propagation is vital in assessing power quality levels throughout the network. As an alternative to the established stationary flicker propagation methods, this paper introduces representative voltage samples that, together with flicker transfer factors, enable the calculation of flicker levels throughout the network at the same voltage level. The shorter 1-s voltage samples are extracted from the instantaneous voltages measured and can represent the longer operating periods of an arc furnace. The calculation of flicker levels with the use of voltage samples is practical and eliminates the need for flicker measurements in an arbitrary network node. Additionally, the flicker levels in nodes under the influence of flicker from multiple arc furnaces can be obtained without the use of superposition factors.
COBISS.SI-ID: 35976965
This article describes an oscilloscope method for eliminating the interference and disturbance voltages for the earthing system measurements of large, extended or interconnected earthing systems in substations where the impedance to earth is very low. The presented oscilloscope method is based on a heavy-current injected method at network frequency. Two ways of obtaining the final result from oscilloscope measurements are described and presented with practical examples. The accuracy of this method using an oscilloscope was confirmed by a comparison with results obtained using conventional methods for practical cases of touch-voltage measurements, i.e., the beat method and the polarity-reversal method. These comparative measurements were made in three substations. The article also describes the advantages of this method.
COBISS.SI-ID: 34702853