The Accelerate Estimation Method of Power System Parameters in Static and Dynamic Processes

Current trends in power system development and the issues they pose have increased the urgency of automatic and emergency control alongside transient electromechanical processes. Such control devices place high demands on mode-parameter estimation algorithms in terms of their speed, accuracy, and transient sensitivity. This paper proposes a rapid estimation algorithm for power system parameters to investigate its optimal settings and applicability in both static and dynamic states. The proposed algorithm is based on signal approximation on sliding window using a multiparameter model, which is highly stable and reliable. The signals modeled in MATLAB/Simulink were used as initial data. From the experimental results, it became clear that the rapid estimation algorithm of the power system parameters showed high accuracy in steady-state mode as well as during transients, and its optimal parameters were identified. The developed algorithm can be used in relay protection, automatic and emergency control devices, and synchronous machine state-monitoring systems. © 2013 IEEE

A Base-Controlled Reaction of 2-Cyanoacetamidines (3,3-Diaminoacrylonitriles) with Sulfonyl Azides as a Route to Nonaromatic 4-Methylene-1,2,3-triazole-5-imines

Reactions of 2-cyanoacetamidines with sulfonyl azides were shown to take place via two different pathways to form a mixture of 1-substituted 5-amino-1,2,3-triazoles 3 and novel 4-methylene-1H-1,2,3-triazole-5(4H)-imine derivatives 4–14. In the absence of a base, 5-amino-1,2,3-triazoles 3 are formed as the only products. The presence of 1.2 equiv. of sodium ethoxide or DBU switches the reaction outcome while involving the cyano group, resulting (after a 1,5-protic shift) in triazoles 4–14 as the only products. The methods were elaborated for the selective and efficient synthesis of triazoles 3 and 4-methylene-1,2,3-triazole-5-imines 4–14 including one-pot synthesis from sodium azide and sulfonyl chlorides. The unusual structure of 4–14 compounds was confirmed by X-ray data and 2D 1H–15N and 1H–13C NMR spectra. The formation of the products was explained by the presence of two strong hydrogen bonds N···H and O···H in these molecules. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimWe gratefully acknowledge financial support of this work by the Russian Science Foundation (18‐13‐00161)

Optimal Management of Energy Consumption in an Autonomous Power System Considering Alternative Energy Sources

This work aims to analyze and manage the optimal power consumption of the autonomous power system within the Pamir region of Republic of Tajikistan, based on renewable energy sources. The task is solved through linear programming methods, production rules and mathematical modeling of power consumption modes by generating consumers. It is assumed that power consumers in the considered region have an opportunity to independently cover energy shortage by installing additional generating energy sources. The objective function is to minimize the financial expenses for own power consumption, and to maximize them from both the export and redistribution of power flows. In this study, the optimal ratio of power generation by alternative sources from daily power consumption for winter was established to be hydroelectric power plants (94.8%), wind power plant (3.8%), solar photovoltaic power plant (0.5%) and energy storage (0.8%); while it is not required in summer due to the ability to ensure the balance of energy by hydroelectric power plants. As a result, each generating consumer can independently minimize their power consumption and maximize profit from the energy exchange with other consumers, depending on the selected energy sources, thus becoming a good example of carbon-free energy usage at the micro-and mini-grid level. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

A Novel Approach of Synchronization of Microgrid with a Power System of Limited Capacity

Currently, active networks called microgrids are formed on the basis of local power supply systems with a small share of distributed generation. Microgrids operating in an island mode, in some cases, have the ability to transfer electricity excess to an external network leading to a synchronization requirement; thus, the optimization task in terms of the system’s synchronization must be considered. This paper proposes a method for obtaining synchronization between microgrids and power systems of limited capacity based on a passive synchronization algorithm, allowing us to connect a microgrid to an external power system with a minimum impact moment on the shaft of the generating equipment. The algorithm application was demonstrated by considering a real-life object in Tajikistan. The simulation was carried out on RastrWin3. The obtained results show that the microgrid generator is connected to an external power system at an angle of 0.3◦ and a power surge of 29 kW, unlike the classical synchronization algorithm with an angle of 6.8◦ and a power surge of 154 kW (a reduction of the shock moment by more than five times). The proposed synchronization method allows us to reduce the resource consumption of the generating equipment and increase the reliability and efficiency of the functioning units of the examined power system. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Selective Synthesis of Azoloyl NH-1,2,3-Triazoles and Azolyl Diazoketones: Experimental and Computational Insights

Here, we report that the reaction of enaminones, from a class of azole series, with sulfonyl azides leads to a difficult-to-separate mixture of two pairs of compounds: (1) 4-azoloyl-NH-1,2,3-triazoles with sulfonamides and (2) azolyl diazoketones with N-sulfonamidines, as a result of the implementation of two competing reactions. On one hand, the electron-donating methyl or methoxy group in the aryl para-position of arylsulfonyl azides favors the production of NH-1,2,3-triazoles together with sulfonamides. On the other hand, the use of highly electrophilic 4-nitrophenylsulfonyl azide promotes the formation of diazoketones and sulfonamidines. It is shown that the direction of each reaction is not only controlled by the nature of the initial enaminones and sulfonyl azides but also depends on the tested solvent. The problem of removing sulfonamides and amidines from the desired products was solved for the first time using new water-soluble enaminones. Based on the experimental and computational studies, the factors contributing to the selective course of alternative reactions were identified, and methods for the synthesis of azoloyl-NH-1,2,3-triazoles and azolyl diazoketones were developed. Density functional theory (DFT) results have shown that the 1,3-dipolar cycloaddition is totally driven toward one single regioisomer with a high asynchronous bond formation, and the introduction of an electron-deficient group in sulfonyl azides induces faster cycloaddition. Additionally, DFT calculations were used to gain further mechanistic insights on the reaction studied here. © 2022 American Chemical Society. All rights reserved.This work was supported by the Russian Science Foundation (grant no. 18-13-00161, prolongation). A.A.H. thanks the computational resources accessed via Iridis4 provided by the University of Southampton

ОСОБЕННОСТИ И ХАРАКТЕРИСТИКА ПОКАЗАТЕЛЕЙ ЗАБОЛЕВАЕМОСТИ РАКОМ ЩИТОВИДНОЙ ЖЕЛЕЗЫ У ЖИТЕЛЕЙ Г. ТОМСКА И ТОМСКОЙ ОБЛАСТИ

The analysis of thyroid cancer incidence and its structure among different populations of Tomsk region is presented. We studied the report documents, the database of the Tomsk regional oncologic dispensary for the period 2008 to 2012. The clinical characteristics of patients with thyroid cancer were summarizes according to sex, age and place of residence. The papillary cancer was the most often diagnosed. It was found that in young patients, thyroid cancer was diagnosed more often in the stage 1 and 2. On the other hand, in elderly patients (above 60 years), thyroid cancer diagnosed at stage 3 and 4. In the Tomsk region, as elsewhere in the world, thyroid cancer is detected more often in women.Представлены результаты анализа заболеваемости раком щитовидной железы среди жителей Томской области, особенности ее структуры среди различных контингентов населения. Были изучены база данных и отчетные документы Томского областного онкологического диспансера за период 2008–2012 гг. Обобщена клиническая характеристика больных раком щитовидной железы в зависимости от пола, возраста и места проживания. В результате анализа установлено, что лидирующее место в морфологической структуре рака щитовидной железы принадлежит папиллярному раку. Выявлено увеличение количества вновь выявленных больных, установлено, что рак щитовидной железы в молодом возрасте чаще диагностируется на ранних стадиях, стадии 3 и 4 при первичной диагностике встречаются преимущественно у лиц старше 60 лет. В Томской области, как и во всем мире, среди больных раком щитовидной железы превалируют женщины

A Base-Controlled Reaction of 2-Cyanoacetamidines (3,3-Diaminoacrylonitriles) with Sulfonyl Azides as a Route to Nonaromatic 4-Methylene-1,2,3-triazole-5-imines

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Synthesis of Non-Aromatic Pyrroles Based on the Reaction of Carbonyl Derivatives of Acetylene with 3,3-Diaminoacrylonitriles

The reaction of 3,3-diaminoacrylonitriles with DMAD and 1,2-dibenzoylacetylene was studied. It is shown that the direction of the reaction depends on the structure both of acetylene and of diaminoacrylonitrile. In the reaction of DMAD with acrylonitriles bearing a monosubstituted amidine group, 1-substituted 5-amino-2-oxo-pyrrole-3(2H)ylidenes are formed. On the other hand, a similar reaction of acrylonitriles containing the N,N-dialkylamidine group affords 1-NH-5-aminopyrroles. In both cases, pyrroles containing two exocyclic double bonds are formed in high yields. A radically different type of pyrroles containing one exocyclic C=C bond and sp3 hybrid carbon in the cycle is formed in reactions of 3,3-diaminoacrylonitriles with 1,2-diaroylacetylenes. As in reactions with DMAD, the interaction of 3,3-diaminoacrylonitriles with 1,2-dibenzoylacetylene can lead, depending on the structure of the amidine fragment, both to NH- and 1-substituted pyrroles. The formation of the obtained pyrrole derivatives is explained by the proposed mechanisms of the studied reactions

Self condensation of enamines mediated by acetylation. A novel approach to 1-(azol-5-yl)-(1E,3Z)-butadiene-4-N,N-dimethylamines

Novel self-condensation of 3-(azol-5-yl)-1,1-dimethylenamines has been found to form new C-C bonds leading to 2,4-(1,2,3-triazole-1,2,3-thiadiazole-3- phenylisothiazole)-(1E,3Z)-5-yl-butadiene-1-amines. The discovered reaction represents a new example of C-H functionalization in unsaturated systems and can serve an efficient synthetic approach to rational design of new 2,4-(diazole-5-yl)-dieneamines. © 2012 The Royal Society of Chemistry