Scientific Journal of KubSAU

Polythematic online scientific journal
of Kuban State Agrarian University
ISSN 1990-4665
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317 kb

VOLTAGE REGULATORS ASYNCHRONOUS GENERATORS

abstract 1101506099 issue 110 pp. 1493 – 1511 30.06.2015 ru 1490
A promising is currently the use of asynchronous generators with capacitive excitation as a source of electricity in stand-alone power systems. Drive asynchronous generators may exercise as a thermal engine and wind wheel wind power plant or turbines of small hydropower plants. The article discusses the structural and schematics of voltage stabilizers and frequency of asynchronous generators with improved operational and technical specifications. Technical novelty of design solutions of the magnetic system and stabilizers asynchronous generator of electricity parameters confirmed by the patents for the invention of the Russian Federation. The proposed technical solution voltage stabilizer asynchronous generators, can reduce the weight of the block capacitors excitation and reactive power compensation, as well as to simplify the control system power circuit which has less power electronic devices. For wind power plants it is an important issue not only to stabilize the voltage of the generator, but also the frequency of the current. Recommend functionality stabilizer schemes parameters of electric power made for direct frequency converters with artificial and natural switching power electronic devices. It is also proposed as part of stabilization systems use single-phase voltage, three-phase transformers with rotating magnetic field, reduce the level of electromagnetic interference generated by power electronic devices for switching, enhance the efficiency and reliability of the stabilizer.
335 kb

VOLTAGE REGULATORS OF SYNCHRONOUS GENERATORS

abstract 1101506100 issue 110 pp. 1512 – 1531 30.06.2015 ru 863
Synchronous generators are the primary source of electrical power autonomous electrosupply systems, including backup systems. They are also used in a structure of rotating electricity converters and are widely used in renewable energy as part of wind power plants of small, mini and micro hydroelectric plants. Increasing the speed and the accuracy of the system of the voltage regulation of synchronous generators is possible due to the development of combined systems containing more stabilizers. The article illustrates the functional schemes of circuit voltage stabilizers and frequency synchronous generators (with electromagnetic excitation and permanent magnet excitation) and describes the features of their work, including two and three-aggregate rotating converters of electricity used in uninterruptible power supply systems. To improve the technical characteristics of the system of stabilization we have proposed functional solutions for stabilizers of synchronous generators made on the base of direct frequency converters and using a transformer with a rotating magnetic field. To improve the reliability of and to improve the operational characteristics of the autonomous independent sources of electricity we suggest creating the main functional blocks and the elements of the stabilization system in a modular way. The functional circuit solutions of voltage regulators of synchronous generators and the characteristics of their work considered in the article, are able to improve the efficiency of pre-design work in the development of new technical solutions for stabilizing the voltage and the frequency in synchronous generators of electrosupply autonomous systems
280 kb

VOLTAMMETRY AND ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY OF MEMBRANE SYSTEMS UNDER STABILIZED DIFFUSION LAYER THICKNESS

abstract 1131509094 issue 113 pp. 1326 – 1342 30.11.2015 ru 1174
The current-voltage characteristics and the number of effective ion transfer, as well as the frequency spectrum of the electrochemical impedance of multilayer ion-exchange membranes in a stable and controllable thickness of the diffusion layer were measured, using the of rotating membrane disk complex. The article presents a comparative analysis of the frequency spectra of the electrochemical impedance of the source and a surface-modified monopolar anion exchange membranes in 0.01 M sodium chloride was made. The process of water molecules dissociation at current densities above the limiting one in 0.01 M sodium chloride solution was studied in detail
151 kb

VOLUMES OF GENERA AND SPECIES OF COLEOPTERA, ELATERIDAE OF THE REPUBLIC OF DAGESTAN

abstract 0921308040 issue 92 pp. 619 – 630 31.10.2013 ru 1262
In the article volumes of genera, species of Coleoptera, Elateridae of the Republic of Dagestan are given
1362 kb

VORTEX TURBULENT FLOWS IN ATMOSPHERES OF PLANETS AND ON THE SUN

abstract 1341710109 issue 134 pp. 1387 – 1411 29.12.2017 ru 370
In this work, we consider two types of vortex currents-cyclones and anticyclones in the Northern and Southern Hemispheres. Numerical modeling of turbulent flows of these types uses the model of the planetary boundary layer developed by the author. The purpose of the study is to test hypotheses about the influence of the Coriolis force on the formation of cyclones and anticyclones in the northern and southern latitudes. The first hypothesis on the direction of circulation in cyclones was verified in the case of axisymmetric radially converging and vertically rising turbulent flows with a natural Coriolis parameter and viscosity. From the obtained data of numerical experiments, it follows that the current in the northern latitudes circulates in a counter clockwise direction, and in the south - in a clockwise direction, in full accordance with the observational data. Thus, we have shown that a cyclonic flow is formed in a turbulent radially converging flow under the influence of the Coriolis force. The second hypothesis on the formation of anticyclones was verified in the case of radially divergent and vertically descending turbulent flows. Because of numerical experiments, it was established that in this case, the current in the northern latitudes circulates clockwise, and in the south - in a counter clockwise direction, which corresponds to observations for anticyclones. To test the effect of the cyclone (anticyclone) center velocity on circulation, a nonstationary 3D model of turbulent flow was developed. Within the framework of this model, flows in cyclones and anticyclones moving at a constant speed, as well as in shear flow, are studied. Some types of loop protuberances on the Sun are explained by the presence of a vortex turbulent flow starting in the bowels of the Sun and encompassing the chromosphere
1453 kb

VYBORG’S PERIOD OF A GREAT RUSSIAN ARTIST NICHOLAS ROERICH

abstract 1231609031 issue 123 pp. 457 – 479 30.11.2016 ru 1469
A Karelian stage in the life of the great Russian artist, Nicholas Roerich, is relatively well-known. However, researchers have not been practically studied the period of residence of the Roerich family in Vyborg. It is known that N. Roerich was friends with the Finnish artist A. Gallen-Kallela, who helped him to remain in Finnish Vyborg in the period of revolutionary events in Russia. From October 1918 to May 1919 the Roerich family lived in Viborg in Ladaunkatu (now Turgenev St.), №8. The painting «Autumn» (1919) was written by the artist during the Vyborg’s period. The painting was created in a fantastic manner which was usual for the artist. Unfortunately, at the moment nothing is known about his other works with views of Vyborg. However, in the catalog of his works, published in the USA in the 1920-es , under the name of each picture is given information about where and when it was created. Thus, under some of the works of the artist is the mark: «Painted in Viborg». So, today we can say about some works of master, which he wrote in Vyborg. In the first place, there are famous paintings of the artist: «Repentance», «Call of the bell. Old Pskov», «Sons of the Heavens», «The heat of the Earth», «Autumn – Vyborg», «Les Miserables (Outcast)», «Treasure» and others. As well, in 1918 at the time of staying the family in Vyborg a number of sketches in "Vyborg Notebook" were made by his son, Svetoslav Roerich, who was then 16 years old. Probably, inexhaustible diligence of Roerich gave a rise to other works with the theme of Vyborg, which scientists do not know because this topic has not been investigated
157 kb

Warm, warmth and internal energy of a body

abstract 1111507038 issue 111 pp. 680 – 694 30.09.2015 ru 946
The article discusses the question of the concepts of heat and internal energy of a body. The analysis of these concepts in the historical aspect and the views of the author, based on the new photon theory of atomic structure were presented in this study. The analysis of the historical aspect of this question tells that the concepts of heat and internal energy of the body for a long time were associated with the concept of caloric, which can flow in the substance. The next step was the identification of the concept of heat with energy linked with the movement and work. In accordance with this, Clausius proved the equivalence of heat and work as the first principle of the theory of heat and introduced the concept of internal energy, which can be increased in two ways - making work on body, and summing heat to it. Thus, energy was the main uniting factor of work and heat. Then, the kinetic theory of heat, as the energy of motion of molecules, was developed by Maxwell and caloric model turned out to be a hindrance in the development of the theory of heat. In fact, the internal energy of the body is determined photons, rotating around charged particles in atoms in their orbitals. The series of photons are combined into a single photon orbital direction of rotation of the photons, which are different from each other. Thus, the body has an internal energy or internal heat. It is due to the energy of photons, orbiting electrons in the outer shell of each atom, as well as around the charged particles - electrons and protons in the nucleus of an atom. This internal energy may be increased by mechanical action on the body, leading to an increase in resulting oscillation frequency of photons around charged particles of atoms and the internal heat contained in the body can flow of the body with a higher concentration of heat to the body with a lower concentration of heat
207 kb

WATER ACCOUNTS IN THE RIVER KUBAN BASIN IN PERSPECTIVE

abstract 0380804002 issue 38 pp. 8 – 25 29.04.2008 ru 2760
Water calculations with an account of quests of water users and water consumers with the supply situation 50, 75, 95 % were done and their results on whole water complex on the branches of economics.
177 kb

WATER PROVISION AND PRODUCTIVITY OF PLANTS OF THE SUGAR BEET DEPENDING ON AGRORECEPTIONS OF ITS CULTIVATION

abstract 0611007020 issue 61 pp. 253 – 263 24.09.2010 ru 2175
Influence of system of the basic processing of soil and system of fertilizers of a sugar beet on accumulation of the general and productive stock of a moisture in the beginning and in the end of vegetation, total water consumption and water consumption factor, and also influence of these agro receptions on productivity and sugar content of root crops is studied
192 kb

WATER QUALITY ASSESSMENT OF THE WATER ENVIRONMENT AND BIOTA IN THE VILUY REGION

abstract 1181604101 issue 118 pp. 1543 – 1561 29.04.2016 ru 526
Numerous revealed negative impacts of the diamond industry and Vilyuiskaya HPP on the aquatic environment and biological objects are more expressed in the change of the hydrochemical regime in water basin of Viluy and as its consequence - in violation of the structural and functional nature of the components of aquatic biota; in the change of he average biomass and abundance of planktonic populations (phytoplankton and zooplankton) and benthic organisms, and in general - in the change of the flow energy in an aquatic ecosystem
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