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1

Earth fault protection supported with adaptive admittance criteria

Lorenc J., Łowczowski K., Staszak B.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 8

132--135

EN

In this paper possibilities for improvement of earth fault protection by adjustment of protective relay settings due to change of neutral point impedance in medium voltage networks are presented.

PL

W artykule przedstawiono zagadnienia dotyczące możliwości poprawy skuteczności działania zabezpieczeń ziemnozwarciowych typu YY0 poprzez dostosowanie wartości nastawczych do zmian spowodowanych modyfikacją sposobu pracy punktu neutralnego w sieci średniego napięcia.

2

Study of influence of measuring system parameters to the value of active and reactive component of the substance electrical conductivity

Gonsor O., Tomasik M.

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

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2017

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Vol. 6, No 1

31--36

EN

Electrical conductivity is an important electrical parameter of the substance, by which you can identify its quality characteristics. Determining the admittance of the substance is crucial. Admittance of the substance as an active element depends on its chemical composition, temperature, voltage that is applied to the measuring circuit and the frequency of the measuring signal. In this regard, it is advisable to carry out a series of experimental tests to determine the effect of these parameters on the admittance of the substance. The object of research is water from different sources of centralized drinking water supply. For theoretical analysis of admittance, water is seen as a multi-element two-terminal, placed in the electric circuit of alternating current. To reduce the methodological error, active and reactive components of electrical conductivity were researched in different frequencies ranges (from 50 Hz to 100 kHz). Investigation of the temperature dependence showed that the active and reactive components of the electrical conductivity are temperature dependent, but the reactive component is less sensitive to change. The dependence of the admittance of the frequency at different levels of the test signal is investigated. The article presents the graphical specification of changing admittance at the change of frequency, at different levels of the test signal. Also, the dependencies of active and reactive components were studied of the electrical conductivity of drinking water from changing test signal U at different frequencies.

3

Znaczenie systemu dopuszczeń pojazdów pożarniczych w kontekście zapewnienia bezpieczeństwa strażaków

Sobór E., Gołaszewska M., Chmiel M., Borusiński M.

Bezpieczeństwo i Technika Pożarnicza

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2015

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Nr 2

97--104

PL

Cel: Celem artykułu jest przedstawienie znaczenia kolejnych etapów procesu dopuszczania do użytkowania pojazdów pożarniczych w kontekście zapewnienia bezpieczeństwa strażaków. Wprowadzenie: Użytkownicy końcowi, decydując się na wybór danego sprzętu pożarniczego, oczekują spełnienia przede wszystkim trzech warunków: bezpieczeństwa, ergonomii i funkcjonalności. Co więcej wysoka skuteczność oraz niezawodność działania wyposażenia i sprzętu wykorzystywanego do działań ratowniczo-gaśniczych przez jednostki ochrony przeciwpożarowej jest warunkiem koniecznym do spełnienia z uwagi na powodzenie prowadzonych działań oraz zapewnienie bezpieczeństwa zarówno osób ratowanych, jak i samych ratowników. Aby wyjść naprzeciw wymaganiom i potrzebom jednostek ochrony przeciwpożarowej w Polsce wprowadzono system dopuszczeń. W niniejszym artykule, na przykładzie pojazdów pożarniczych, przedstawiono kolejne etapy procesu dopuszczenia wyrobów do użytkowania oraz ich znaczenie dla bezpieczeństwa strażaków. Omówiono aktualne przepisy prawa w zakresie dopuszczania pojazdów do użytkowania oraz przedstawiono główne założenia oraz przebieg procesu dopuszczenia. Zwrócono również uwagę na znaczenie nadzoru nad udzielonymi dopuszczeniami, realizowanego na drodze kontroli dopuszczeń. Poruszono również kwestie posługiwania się świadectwem dopuszczenia, odpowiedzialności za wyrób oraz wprowadzania zmian mogących mieć odzwierciedlenie w zapisach świadectwa dopuszczenia. Metodologia: W artykule przeanalizowano literaturę przedmiotu. Treść opracowano w oparciu o aktualnie obowiązujące przepisy prawa w zakresie zarówno wprowadzania samochodów pożarniczych do użytkowania, jak i ich klasyfikacji, podziału oraz oznaczenia. Literaturę stanowią dodatkowo procedury opracowane przez Jednostkę Certyfikującą CNBOP-PIB. Wnioski: System dopuszczeń oparty na ściśle określonych wymaganiach i sposobie postępowania stanowi skuteczne narzędzie selekcji pojazdów pożarniczych trafiających na polski rynek. Znaczenie tego systemu dla bezpieczeństwa jednostek ochrony przeciwpożarowej jest znaczące. Dostarcza on bowiem odbiorcom szereg istotnych informacji na temat przedmiotowych wyrobów, co ułatwia podjęcie decyzji w zakresie zakupu pojazdu wprowadzonego do użytkowania na zasadach zgodnych z aktualnie obowiązującymi przepisami prawa oraz spełniającego nie tylko oczekiwania samych użytkowników końcowych, ale i przede wszystkim wymagania z uwagi na ich bezpieczeństwo.

EN

Aim: The purpose of this article is to expose the importance of the admittance process for firefighting vehicles from the viewpoint of firefighters’ safety. Introduction: During the selection process, involving firefighting equipment, end users focus on the satisfaction of three conditions; safety, ergonomics and functionality. Moreover effectiveness and equipment reliability during operations are prerequisites, which must be satisfied, to achieve successful outcomes and ensure the safety of incident victims and firefighters. In order to satisfy demands and needs of Fire Service establishments, Poland introduced an admittance process. This article has identified sequential stages of the admittance process, involving equipment destined for use, using vehicle acquisitions for illustrative purposes and discussed the significance of the process from the viewpoint of firefighters’ safety. In parallel with discussions about current legislation dealing with admittance of equipment, the article exposed main assumptions used and the course of the admittance process. Attention was also drawn to the issue of supervision over the granting of certificates od admittance, performed as part of the admittance control mechanism. Additionally, the article discussed issues associated with the use of certificates od admittance, product liability and introduction of modifications to equipment, which may be reflected in certificates of admittance. Methods: The authors carried out an analysis of literature dealing with the topic. The article was based on sources of law, which are currently in force and apply, not only to bringing into use but also classification, division and rules of designation. Moreover, procedures developed by CNBOP-PIB Certification Department formed part of the literature source. Conclusions: The admittance process, based on specific requirements and procedures, is an effective tool for selection of firefighting vehicles, from those available on the Polish market. The importance of this system to the safety of Fire Service personnel is significant. It provides users with important information about products. Such information simplifies purchasing decisions involving vehicles introduced for use in accordance with current legislation, which, not only satisfy user expectations but above all address requirements concerning safety.

4

Influence of composition of the near-surface graded-gap layer on the admittance of metal-insulator-semiconductor structures based on graded-gap MBE n-Hg₁₋xCdxTe in wide temperature range

Voitsekhovskii A. V., Nesmelov S. N., Dzyadukh S. M.

Opto-Electronics Review

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2014

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Vol. 22, No. 4

236-244

EN

Influence of the CdTe content in a near-surface graded-gap layer on the admittance of MIS-structures fabricated on the basis of heteroepitaxial Hg₁₋xCdxTe (x = 0.22−0.23 and 0.31−0.32) films grown by molecular beam epitaxy was investigated in a wide temperature range. It is shown that a temperature drop from 77 K to 8 K results in a decrease of hysteresis of the capacitance-voltage (C−V) characteristics and a decrease of frequencies which corresponds to a high-frequency behaviour of C−V characteristics of MIS-structures based on n-HgCdTe (x = 0.22–0.23) with and without graded-gap layersand also for MIS-structures based on n-HgCdTe (x = 0.31–0.32). Temperature dependences of the resistance of the epitaxial film bulk and differential resistance of the space-charge region (SCR) in strong inversion mode were studied. The experimental results can be explained by the fact that for MIS-structures based on n-HgCdTe (x = 0.22–0.23) with the graded-gap layers and for MIS-structures based on n-HgCdTe (x = 0.31–0.32), the differential resistance of SCR is limited by Shockley-Read generation at 25–77 K. Differential resistance of SCR for MIS-structures based on n-HgCdTe (x = 0.22–0.23) without the graded-gap layers is limited by tunnelling through deep levels at 8–77 K.

5

Admitancyjne zabezpieczenia ziemnozwarciowe dla sieci średnich napięć

Lorenc J.

Automatyka Elektroenergetyczna

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2008

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Nr 3 (60)

10-15

PL

Dzięki zrealizowaniu wielu badań opracowano i wprowadzono do eksploatacji w sieciach średnich napięć kilkanaście tysięcy admitancyjnych zabezpieczeń ziemnozwarciowych typu Yo>, Go>, Gok, Bok oraz YYo. Ich skuteczność wykrywania zwarć doziemnych jest relatywnie duża i dobrze oceniana. W upowszechnianiu tych zabezpieczeń istotne znaczenie mają publikacje i opracowania dotyczące sposobu ich właściwego instalowania i użytkowania. W artykule przedstawiono fragmenty jednej z takich publikacji, która ukazała się na rynku w ostatnich miesiącach. Przedstawione fragmenty dotyczą przede wszystkim zasad doboru wartości nastawczych zabezpieczeń admitancyjnych.

EN

Due to many researches there were more than ten thousands admittance earth fault protections (Yo>, Go>, Gok, Bok and YYo) elaborated and introduced to the MV networks.Their efficiency of detecting earth faults is relatively high and considered as a good one. As far as making the protections common is concerned the publications and papers that concern ways of installing and using the protections are significant. In the article there are presented few excerpts from one publication that has been published in the last few months. The presented excerpts concern especially the base of choosing the set up value of admittance protections.

6

An impact of physical phenomena on admittances of partially-depleted SOI MOSFETs

Tomaszewski D., Łukasiak L., Gibki J., Jakubowski A.

Journal of Telecommunications and Information Technology

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2001

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nr 1

57-60

EN

An influence of the selected physical phenomena: impact ionization in silicon and time variation of internal electric field distribution in partially-depleted (PD) SOI MOSFETs on several C-V characteristics of these devices is presented. The role of avalanche multiplication in the so-called "pinch-off" region is discussed in a more detailed way. The analysis is done using a numerical solver of drift-diffusion equations in silicon devices and using an analytical model of the PD SOI MOSFETs. The calculations results exhibit the significance of proper modelling of the phenomena in the floating body area of these devices.

7

Admittance Analysis at Electrochemical Quartz Crystal Microbalance in Fast Dynamic Measurements

Plausinaitis D., Raudonis R., Daujotis V.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 4

559-565

EN

A method is proposed for measuring admittance in cyclic voltammetry at an electrochemical quartz crystal microbalance. The main idea of this method is to measure admittance spectrum in a series of repetitive potential cycles by using one perturbing frequency in one potential cycle.

8

Admittance measurements on CIGS solar cells

Kubiaczyk A., Nawrocka M., Igalson M.

Opto-Electronics Review

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2000

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Vol. 8, No. 4

378-381

EN

Thin film solar cells based on polycrystalline CIGS absorbers are one of the most promising candidates for the low-cost and efficient large-scale solar energy conversion devices. Electronic transport properties of ZnO/CdS/Cu(In,Ga)Se₂ solar cells were investigated by means of admittance measurements in a frequency range from 600 Hz to 1 MHz and a temperature range from 80 to 300 K. Dependent on the sample under investigation, one characteristic frequency (inflection point) corresponding to an activation energy between 80 and 160 meV or two points corresponding to an activation energy about 400 meV have been observed. Analysis of the measured frequencies and obtained activation energies provides information on the equilibrium Fermi level position at the CdS/CIGS interface.