BENCHMARKING W ELEKTROENERGETYCZNYCH SYSTEMACH DYSTRYBUCYJNYCH

The article presents an analysis of the reliability indicators used in the electric power systems structures of Polish and Europe, in the context of benchmarking at the level of functional and operational, the aim of which is to identify optimal methods for assessing and evaluating the possibility of indicating the reference values. In addition, noted the impact of electricity grid structure on the value of the currently used indicators of reliability.Artykuł prezentuje analizę stosowanych wskaźników niezawodności zasilania w strukturach elektroenergetycznych Polski i Europy, w kontekście benchmarkingu na poziomie funkcjonalnym i operacyjnym, której celem jest wskazanie optymalnych metod oceny i ocena możliwości wskazania wartości referencyjnych. Ponadto wskazano wpływ struktury sieciowej na wartości aktualnie stosowanych wskaźników niezawodności zasilania

Signs of geoeffective space weather events in cosmic rays during the first half of the solar cycle 24

Solar originating events are continually evident in galactic cosmic ray (GCR) flux registered at the ground by neutron monitors. We analyze time intervals of sporadic Forbush decreases (Fd) observed by neutron monitors (NM) during the first half of solar cycle 24. We consider NMs data, as well as, solar, heliospheric and geoma - gnetic activity parameters, around those periods, using different mathematical tools. Subsequently, an impact of space weather phenomena on energy infrastructure is well known, in the further step we consider logs from one of the Polish transmission lines operators during the time intervals of Fds. Based on the data from the Ins- titute of Meteorology and Water Management-Polish National Research Institute we exclude from the analysis the weather-related failures. We found that the increase in the superposed averaged number of failures appears around Forbush decreases

Electromagnetic therapeutic coils design to reduce energy loss

The article introduces the problem of power loss reduction in applicators used in magnetotherapy. To generate magnetic field whose distribution is optimal and to reduce the power loss, the authors establish a set of parameters to evaluate the model of device. Results make it possible to infer that the real power input necessary to operate the magnetic field generator properly may vary significantly depending on construction and localization. The issues raised in this paper should be treated as a basis for further discussion on the construction of applicators used, e.g., in Transcranial Magnetic Stimulation

Electromagnetic therapeutic coils design to reduce energy loss

The article introduces the problem of power loss reduction in applicators used in magnetotherapy. To generate magnetic field whose distribution is optimal and to reduce the power loss, the authors establish a set of parameters to evaluate the model of device. Results make it possible to infer that the real power input necessary to operate the magnetic field generator properly may vary significantly depending on construction and localization. The issues raised in this paper should be treated as a basis for further discussion on the construction of applicators used, e.g., in Transcranial Magnetic Stimulation

Analiza możliwości poprawy niezawodności napowietrznej linii 15 kV narażonej na katastrofalne oblodzenie w warunkach polskich

The paper is a result of a synergic cooperation of two academic teams, i.e. power engineering and mechanical teams, and a distribution system operator. A real 15 kV overhead line exposed to a catastrophic load of ice and rime was analyzed and three solutions to improve the reliability of the tested object in such conditions were examined. Authors considered: shortening the length of the line spans, heating the main line with increased current and rebuilding the overhead line to a cable line. The researches worked out a FEM model taking into account the newest normatives, simulated the model, experimentally increased the load on the real line with measured wire temperature, and performed multi-variant calculations to determine indicators of reliability, i.e. SAIDI and SAIFI. The analyses were followed by conclusions thanks to which the reliability of power lines exposed to catastrophic icing could be increased. These inferences should be considered and applied by all distribution system operators in Poland.Praca jest efektem synergicznej współpracy dwóch zespołów akademickich: elektroenergetycznego i mechanicznego oraz operatora systemu dystrybucyjnego. Analizie poddano rzeczywistą, napowietrzną linię średniego napięcia 15 kV narażoną na katastrofalne obciążenia lodem i szadzią. Zbadano możliwość zastosowania trzech rozwiązań mogących poprawić niezawodność badanego obiektu w takich warunkach. Rozważono: skrócenie długości przęseł linii, podgrzewanie magistrali zwiększonym prądem roboczym oraz przebudowę linii do linii kablowej. W celu realizacji pracy wykonano badania modelowo-symulacyjne MES z uwzględnieniem najnowszych wytycznych normatywnych, zrealizowano eksperyment dociążenia linii wraz z pomiarem temperatury przewodów oraz przeprowadzono wielowariantowe obliczenia niezawodnościowe prowadzące do wyznaczenia wskaźników SAIDI i SAIFI. W wyniku szczegółowych analiz sprecyzowano wnioski końcowe pozwalające na zwiększenie niezawodności linii elektroenergetycznych narażonych na katastrofalne oblodzenie, które powinny być rozważone i stosowane przez wszystkich operatorów systemów dystrybucyjnych w Polsce

Evaluating the relationship between strong geomagnetic storms and electric grid failures in Poland using the geoelectric field as a GIC proxy

We study intense geomagnetic storms (Dst < −100nT) during the first half of the solar cycle 24. This type of storm appeared only a few times, mostly associated with southwardly directed heliospheric magnetic field Bz. Using various methods such as self-organizing maps, statistical and superposed epoch analysis, we show that during and right after intense geomagnetic storms, there is growth in the number of transmission line failures. We also examine the temporal changes in the number of failures during 2010-2014 and find that the growing linear tendency of electrical grid failure occurrence is possibly connected with solar activity. We compare these results with the geoelectric field calculated for the region of Poland using a 1-D layered conductivity Earth model

Electricity distribution management Smart Grid system model

This paper presents issues concerning the implementation of Smart Grid solutions in a real distribution network. The main components possible to quick implementation were presented. Realization of these ideas should bring tangible benefi ts to both customers and distribution system operators. Moreover the paper shows selected research results which examine proposed solutions in area of improving supply reliability and reducing energy losses in analysed network