February 3rd

A multi-pulse diode rectifier with a coupled three-phase reactor

The article presents the principle of operation, design method, and results of laboratory and simulation tests of a 24-pulse power network converter system with direct-voltage output, the concept and practical realisation of which was worked out within the framework of a research project financed by the State Committee for Scientific Research.

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February 2nd

Advantages of changing 3-phase arc furnaces asymmetry estimation criteria in international and european standards

The criteria for estimating the asymmetry of arc furnace circuit impedances, referring to the theory of symmetrical components, have been presented. In contrast to the criteria recommended as yet by IEC and CENELEC, they give homogeneous estimation of asymmetry of circuit impedances, heating powers and unbalance of arc currents.

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February 1st

Passive Filters for Minimum Life Cycle Cost

Harmonic currents can originate from systems that do not contain energy and in which the sign of the current matches that of the voltage throughout the cycle (e.g. a phase-angle controller for an incandescent lamp). The term ‘wattless current’ is sometimes applied to harmonic currents that do not have substantial voltage harmonics of the same orders to multiply them. The result is a product of current and voltage that is zero. Those harmonic currents have a lot in common with reactive currents:

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Optimal placement and sizing of distributed generator units using genetic optimization algorithms

In this article the authors describe how genetic optimization algorithms can be used to find the optimal size and location of distributed generation units in a residential distribution grid. Power losses are minimized while the voltage profile is kept at an acceptable level. The methods is applied on a system based on an existing grid topology with production and residential load data based on measurements. Different scenarios are chosen to run the algorithm.

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