In the last years controlled switching became an effective method to reduce switching transients which is documented by several publications – especially of CIGRE. Controlled switching is most commonly used for switching capacitor banks. Even though uncontrolled energisation of power transformers can lead to very high inrush current transients whose maximum values can exceed many times the rate...

In many text books and papers such as [1]-[5], it is possible to find descriptions about shunt fault calculations and about the influence of the three-phase transformer connection Dyn on the fault currents distribution through distribution transformers. In [6] is described a method for digitally simulating a three-phase power system which is subjected to a fault at one location with blown fuse ...

Abstract—In this paper, the equivalent circuit of the ideal singlephase power transformer with its appropriate voltage current measurement was presented. The calculated values of the voltages and currents of the different connections single phase normal transformer and the results of the simulation process are compared. As it can be seen, the calculated results are the same as the simulated res...

In this paper, a review of PV inverters is reported based on converter characteristics as the number of energy processing stages, the presence of a transformer (high-frequency or 50Hz transformer), and the adopted configuration of the PV field. In particular, the considered solutions have been evaluated depending on efficiency, input current ripple and life-time of the capacitors coupling with ...

Several precise laboratory methods are now available for the determination of the ratio and phase angle of current transformers. 1 These, however, all require a considerable amount of special apparatus, such as carefully calibrated noninductive shunts and very sensitive alternating-current detectors, and are therefore not suited for use under shop or central-station conditions. The task of comp...

This paper presents the design and analysis and of the proposed zero voltage zero current switching (ZVZCS) full bridge dc-dc converter with transformer isolation and current doubler rectifier for high power and high performance by introducing ZVS for lagging leg and ZCS for leading leg operation It has a simple and robust structure with asymmetrical shifted pulse width modulation technique. Th...

Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms ...

This paper proposes a wireless ZigBee technology to monitor the parameters of the transformer. The transformer parameters such as voltage, current, power factor and temperature can be monitored through wireless ZigBee technology. Embedded Ethernet is used to develop client and server applications. Acquisition of voltages, currents, temperatures, active and reactive power, controlling the switch...

harmonics have become an important issue in modern power systems. the widespread penetration of non-linear loads to emerging power systems has turned power quality analysis into an important operation issue under both steady state and transient conditions. this paper employs an extended harmonic domain (ehd) based framework for dynamic analysis of long term analysis over voltages during the tra...

Original scientific paper Measurement of grid voltage harmonic components is an important part of power quality measurements. Current high voltage transformers with iron core are not linear and cannot easily be used for accurate measurement of "polluted" voltages in wide frequency range. In this paper, design details of a new coreless voltage transformer for power quality measurement are given....