Scientific Journal of KubSAU

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

ANALYSIS AND ACCOUNTING OF POWER LOSSES WHEN ENERGY TRANSIT AND THEIR DISTRIBUTION AMONG PARTICIPANTS OF ENERGY EXCHANGE

abstract 1331709060 issue 133 pp. 786 – 796 30.11.2017 ru 387
The work is done in scientific and practical directions for minimization of power losses in transmission of electricity to local distribution networks between the actors of the energy (producers and consumers) of energy-saving technologies focused on technological activities such as modernization and reconstruction of networks. Quite often in various circuits of power systems, it is advisable to transfer energy and its power through intermediate (transit) nodes. Structural changes in the electricity sector, at present, are mainly associated with the introduction of market relations between the subjects of energy exchange; therefore, in this work special attention is paid to the problem of calculating the power losses, as it is nonlinearly dependent on the power at the nodes and branches of a network. It should be noted that the nodes in problems transit capacity could be both sources and consumers. The latter necessitated the need for search of possible ways to reduce transportation losses of energy due to both the improvement and optimization of distribution networks and through the use of intermediate transit nodes. It follows that the transportation problem in this formulation is more General and expands the possibilities of optimization of power losses for the local subsystems of the energy clusters. The work is composed of the transport matrix for solving problems transit capacity, where the algorithm taking into account the distinctive features of which consist in the use of continuous numbering of sources and consumers in the matrix, and any node can be a transit country. The transit capacity ii-th node Zii=0, and the dimension of the matrix in contrast to the previously considered tasks has (n+m) (n+m) and it remains square as all the transport problems of linear programming. Transit variables Xii are included in the solution of the problem with a minus sign, and all transit variables are considered basic. From the above example in the work of a number of branches of a network is minimal, which significantly reduces the cost of building and maintaining the network, and the solver minimizes the power loss between the subjects of energy exchange and, as a result to savings from the standpoint of cost of construction of the network and the management of overflows of energy in it
146 kb

AUTONOMOUS HYBRID POWER PLANTS

abstract 1241610095 issue 124 pp. 1439 – 1450 30.12.2016 ru 389
The article discusses the features of design and operation in the different modes of functioning of autonomous hybrid power plants based on renewable and traditional energy sources. We have given a structural scheme of such a plant. It is shown that the algorithm of the system in the autumn-winter period should be adjusted according to the monthly monitoring; and standby generator of independent source can be run at a deeper discharge of batteries. It is known that the most expensive and the weakest link in the solar PV plants is rechargeable battery. In addition, the larger the number they have in the system, the more complicated the fulfillment of all conditions of proper operation is. We have proposed to extend the lifetime of batteries through the use of passive balancing, which allows to increase the reliability of operation and reduce the cost. It is shown that a real possibility of improving the technical and economic performance of autonomous hybrid power plants is their execution on the basis of solar photovoltaic power plants. We have also discussed the features of construction and operation of hybrid power plants, which will increase the efficiency of preliminary works on development of high-performance structural circuit design of the stations
263 kb

SOFTWARE IMPLEMENTATION OF THE V.V.LEONTIEF MODEL IN C#

abstract 1311707032 issue 131 pp. 387 – 403 29.09.2017 ru 389
The article considers a solution for an economy prognosis formation task in different industries and service sector. In addition, it contains a review of mechanism of an intersectoral balance and theoretical components of V.V. Leontief linear economic model of intersectoral balance. Premises of mathematiceconomical apparatus usage and practical usage in economy planning of many world countries and also results of this apparatus working making that countries’ economic condition “almost balanced” are studied. Inferences of “Input–Output” method significance in economy planning for company groups and country in general are made in this article too. Solution of program product for calculations and analysis development necessity is substantiated. In this program, output of reports is envisaged. Practical example of intersectoral balance task with the developed program is given in article and accuracy of calculations is approved. Program product structure and development tools are described. The program can be used as a tutorial for students studying on economical directions for economic indicators calculation experience gaining
189 kb

SPECTRAL CHARACTERISTICS OF THE SINUSOIDAL MINIMUM (FREQUENCY) SHIFT-KEYING

abstract 1321708045 issue 132 pp. 559 – 568 31.10.2017 ru 389
Signals with the sinusoidal minimum (frequency) shift-keying (SMSK) which impulse form depends on parameter µ are considered. Expression for power spectral density (PSD) of SMSK signals at various values of parameter µ is obtained. Results of PSD calculations and effective bandwidth of signals by various criteria are presented
161 kb

THE INFLUENCE OF METHODS USED TO PREPARE FLAX SEEDS FOR PRESSING ON THE OUTPUT AND QUALITY OF OIL

abstract 1261702010 issue 126 pp. 141 – 154 28.02.2017 ru 391
Analytical survey has revealed that technologies of flaxseed oil processing used nowadays are able to produce technical flaxseed oil if the output is high and food flaxseed oil if the output is low. The objective of this work is to reason the most effective method to increase the output of food flaxseed oil while keeping its quality high. In this article a comparison has been made between single cold pressing of flaxseeds without preliminary preparation with microwave processing, as well as traditional (conductive) heating with traditional heating under vacuum. The object of the research is samples of flaxseeds (high quality variety VNIIMK-620 which contains 56.28% of linolenic acid in its fatty acid composition. It has been established, that the use of preliminary microwave processing enables to increase the output of oil compared to a single cold pressing without any processing, whereby the mass content of oil in oil cake can be reduced by 2.2%. At the same time the indicators of acid number and peroxide value are increased by 0,05 mg KOH/g and 0.37 mmol of active oxygen/kg correspondingly. Preliminary traditional heating of seeds before cold pressing enables to increase the output of oil, though not considerably, compared with preliminary microwave processing. At the same time the changes in acid number and peroxide value are similar to cold pressing with microwave processing. The use of vacuum when heating seeds in a traditional way does not influence the output of flaxseed oil but enables to decrease acid number and peroxide value to the level which is characteristic for the oil in original seeds. Thus, it is reasonable to use preliminary microwave processing under vacuum before cold pressing with the view to produce food flaxseed oil of high quality in terms of oxidative deterioration and the increase of its output
226 kb

TECHNICAL PROVIDING FOR THE SYSTEM OF PROCESSING KUBAN SOIL

abstract 1241610020 issue 124 pp. 390 – 402 30.12.2016 ru 394
The system of the main handling of the soil on an agrolandscape basis in the conditions of Kuban is analyzed and in relation to it the technical supply promoting competitive production of crop production is proved. Conservation and expanded production of humus of the Kuban chernozems is possible only in case of observance of recommendations and the balanced biologically adaptive system of agriculture providing improvement of water and physical and chemical properties of the arable land in various agrolandscapes due to observance of crop rotations, the technology space, the boardless, surface and "zero" treatments with creation of a favorable phytosanitary situation, use of a crop residue remaining balance, green manure, a fertilizer, manure and composts. The application was recommended in the system and technicians of new generation with automated control systems and work quality control, the sparing tradable systems, admissible weight with use of navigation aids and GPS is proved. We have suggested a system machine for soil cultivation in the Kuban region, it radically changes technologies, reduces the nomenclative list of the used equipment, facilitates servicing and operation of machines, improves rhythm, threading of production processes and complexity of the performed works. All this promotes decrease in capital investments and a work gain in productivity. The offered technical supply of system of the main handling of the soil for conditions of the Krasnodar region is proved taking into account agrolandscapes and evidence-based system of agriculture, auxiliary the main component - resource-saving system of the tillage machines which are qualitatively carrying out agrorequirements, reducing costs and promoting the increased product competitiveness of crop production
363 kb

CONSTRUCTION AND CALCULATIONS FOR DEVICES FOR DRYING CHICKEN MANURE

abstract 1341710085 issue 134 pp. 1046 – 1054 29.12.2017 ru 395
The article presents innovative technologies and developed methods and devices for drying chicken manure. Ways of their optimization on the basis of screw aggregates and a calculation technique for introduction in production are offered. The results of a long-term research into the search for and development of innovative technologies for the construction of a methodology for calculating not only a device for drying chicken manure with subsequent introduction into production, but also a device for drying bulk materials of agricultural purpose are shown. An example of thermal calculation and selection of the parameters of a drying device is shown on the basis of screw aggregates
305 kb

OPTIMIZATION OF THE MAINTENANCE SYSTEM OF STATION AND HARVESTING UNITS WITHIN THE FRAMEWORK OF TECHNOLOGY OF «NEVEYKA»

abstract 1241610073 issue 124 pp. 1147 – 1161 30.12.2016 ru 396
Using queuing theory (QT) for the new technology of harvesting of grain crops by the method of «Neveyka», the method of optimal designing of maintenance system and elimination of failures of units used in cleaning technology and post-harvest processing of grain has been considered. On the basis of a systematic approach, taking into account the probabilistic nature of the change of operating factors the methodical directions of validity test of the adoption of the Poisson distribution in the calculation of operating modes were substantiated to optimize maintenance level units and eliminate failures in the operation of the machines, the probability of failure-free operation of harvesting and transport aggregates. The probability of failure-free operation of each type of units used in the cleaning of grain depends on their number and intensity of service. According to the numerical value the probability of failure-free operation of units is equal to the probability of idle units for maintenance and elimination of failures. Since it is impossible to determine separately the value of the probability of failure-free operation for all types of units and all kinds of services at different operating conditions the generalized solution has been offered, this solution is applicable to any serviced unit during both the technical inspection and elimination of failures. By specifying the desired value of the probability of failure-free operation of harvesting units, according to their number we can determine the appropriate ratio between the average length of service and the average period of time between incoming service requirements (technical inspection and elimination of failures) from one unit
367 kb

MATHEMATICAL MODELING OF ELECTRO TECHNOLOGICAL OZONIZATION OF EGG STORES OF POULTRY FARMS

abstract 1211607098 issue 121 pp. 1619 – 1632 30.09.2016 ru 397
Sanitization of eggs is an essential way to fight bacteria, fungi and other microorganisms. Hatchability of eggs and the safety of day-old chicks are dependent on the quality of eggs processing. Leading scientists of our country have proved high efficacy of ozone application for processing of hatching eggs. To obtain a positive result by this method of sanitizing hatching eggs ozone, it is necessary to create a uniform concentration of ozone around the egg store volume. Decrease in ozone concentration from the set point may result in insufficient exposure to pathogens and because of this, may reduce hatchability. Significant excess of ozone concentration from the set point can kill the embryo. Because of mathematical modeling of electro eggs ozone treatment process, there was a mathematical model of the process of electroozonation of egg stores of poultry farms. This model takes into account decomposition of ozone on the surface of eggs and decomposition of ozone on the walls of an egg store. This mathematical model proves the desired control action at different initial data, such as: the required concentration of ozone in the egg store, the number of eggs, egg store geometric dimensions, the fan power, the design parameters of the discharge unit, the location of the ozone generator in the room
309 kb

THE DEVICE FOR STORING AGRICULTURAL MACHINERY IN PROTECTED FORM IN OUTDOOR AREAS

abstract 1241610017 issue 124 pp. 330 – 345 30.12.2016 ru 397
The carried out analysis studies the influence of various factors on the preservation of agricultural products and shows that it is largely determined by design features of machinery and technological methods of use. The efficiency of agricultural and mobile trailer machines has been forming by service and storage. Low quality of work associated with the storage of agricultural machines is conditioned by the fact that the lack of financial capacity of rural producers on acquisitions of modern equipment and materials for carrying out the preparation of for long storage, and also the construction of modern agricultural machinery storage sites. If a car can be fully or partially protected from the solar radiation, rain and snow, simply by removing it in the room, under a canopy or covered with a protective cover, by the formation of condensation on the surface of the machine units and parts these ways to protect do not work. Enhancing of preservation of agricultural machinery is possible when protecting the vehicles from atmospheric precipitation in the form of snow and rain, influence of solar radiation, and also due to the change heat exchange processes of the machine with the environment that prevents the formation of moisture condensate on its surface, ie. we have to create conditions when cooling rate at which the surface of the machine would be equal to or less the rate of cooling air. This is possible through the use of a special design, which would prevent the intense heat radiation of the machine into the environment, ie, would reflect heat rays using its surface and return them to its surface and thus fulfill the role of the heat shield
.