Wyniki wyszukiwania - Biblioteka Nauki

1

Validation of aperiodic and oscillatory stability calculations in a practical power systems

100%

Razzhivin I. , Suvorov A. , Andreev M. , Gusev A.

Przegląd Elektrotechniczny

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2021

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tom R. 97, nr 6

136--139

EN

The stability of electric power systems is one of its most important properties. This article discusses small-disturbance rotor angle stability: aperiodic and oscillatory. The authors consider, typically for stability analysis, the numerical integration methods by modeling in known numerous digital software simulation tools and propose a method for validating of simulation results by benchmark tool instead of field data. The feasibility of the proposed approach is clearly illustrated by the given fragments of the corresponding experimental studies.

PL

Stabilność systemów elektroenergetycznych jest jedną z jego najważniejszych właściwości. W artykule omówiono stabilność kątową wirnika o małych zakłóceniach: aperiodyczną i oscylacyjną. Autorzy rozważają, typowo dla analizy stabilności, metody integracji numerycznej poprzez modelowanie w znanych licznych narzędziach do symulacji oprogramowania cyfrowego i proponują metodę walidacji wyników symulacji za pomocą narzędzia wzorcowego zamiast danych terenowych. Wykonalność proponowanego podejścia wyraźnie ilustrują podane fragmenty odpowiednich badań eksperymentaln.

2

Properties of chirped periodic layered medium with metamaterial layers

80%

Garus J. , Garus S. , Błoch K. , Nabiałek M. , Szota M.

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tom Vol. 66, nr 1

13--19

EN

Purpose: The purpose of the article was to investigate the absorption and reflectance properties of chirped periodic layered medium with metamaterial layers. Design/methodology/approach: The use of the algorithm TMM (Transfer Matrix Method) allows to determine the absorption and reflectance for the quasi one-dimensional multilayer structures. Can be analysed structure constructed with RHM (right-handed materials) and LHM (left-handed materials) with layers of any thickness and arranged in any way. It is possible to analyse lossy dispersive materials. Findings: In all the cases studied linear shift in the peaks with an increase in the k coefficient was observed. In all cases there was a shift to higher wavelengths. Noted an increase in the intensity and broadening half-width of the peaks. Research limitations/implications: The simulation was carried out only for the binary structure in the visible light range. Practical implications: Computer simulations allow us to design material with specified properties at a lower cost. The use of chirped periodic layered media allows to shift and broadening of the peak in the required range of work for mirrors or filter. Originality/value: Absorption and reflectance for chirped periodic layered systems using metamaterials layers have not yet been thoroughly investigated. Research can contribute to the implementation of mirrors with specific nonlinear properties.

3

Transmission in combination of structures

80%

Garus S. , Garus J. , Szota M. , Nabiałek M. , Gruszka K. , Błoch K.

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tom Vol. 64, nr 2

110--117

EN

Purpose: The paper investigated the effect of the combination of two structures on the transmission of electromagnetic waves as a multilayer filter. Examined how the combination of two structures affect the properties of the filter. As a component materials of structures used both right-handed material (RHM) and left-handed (LHM). Design/methodology/approach: Analysis was performed using a matrix method for calculating the superlattice transmission. The influence of combination of two types of multilayer systems: periodic (binary superlattice) and aperiodic (Severin’s and Thue-Morse’s superlattices). Findings: Studies have shown the structure of the transmission band of the structures, which is dependent on the polarization of the incident wave. Combination of various structures are not commutative, and therefore their transmission maps are not equal. Research limitations/implications: The structures analyzed in the work consisted of a lossless material, isotropic and non-dispersive. An important analysis would be lossy dispersive materials. You should also examine the impact would have a separating layer structure and the influence of defects on transmission properties of superlattices. Practical implications: The test structures may be used as filters of electromagnetic radiation. Placing the filter characteristics of the two structures allows pre-filtering an electromagnetic wave, in order to obtain a structure suitable for applications. Originality/value: The paper shows how combination of two periodic and aperiodic structures affect the propagation of electromagnetic waves in a multi-layered system. The analysis was based on the determination of unpolarized transmission maps for complex structures.

4

Infrared transmission in aperiodic structures

80%

Szota M. , Nabiałek M. , Garus S. , Garus J. , Błoch K.

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tom Vol. 64, nr 2

213--218

EN

Purpose: The analysis of the electromagnetic wave transmission having a wave length near infrared propagating in multilayer structures made of materials GaP and CaF2. Analyzed was the influence of periodicity distribution of layers in the material properties and the presence of photonic forbidden gap for selected wavelengths of the electromagnetic wave. Design/methodology/approach: Maps transmission, which was performed by the analysis were obtained using a matrix method. Was investigated wave propagation wavelength range of infrared radiation in periodic binary multilayers and aperiodic Severin and Thue-Morse superlattices. Findings: It has been shown the structure of the transmission band depending on the type of polarization of the multilayer system. Properties of Thue-Morse superlattices were similar to binary superlattices but differed from the behavior of electromagnetic waves in aperiodic Severin superlattices. Research limitations/implications: The simulation was not considered the impact of losses in the material for propagating electromagnetic wave. Practical implications: Multilayer materials, which have photonic band gap, can be used as filters for electromagnetic radiation can improve the performance of night vision or electromagnetic waves multiplexers. Originality/value: Transmission properties of multilayers were examined in visible light but not for infrared light.