Power Balance Management of an Autonomous Hybrid Energy System Based on the Dual-Energy Storage

The urgent task of modern energy is to ensure reliable and efficient power supply to consumers, even those located in remote, far end places. A hybrid energy system with renewable energy sources is a promising way to ensure such a process. A characteristic feature of the modes of such systems, especially with high penetration levels of renewable energy sources, is the presence of ripples in the charge–discharge currents of the batteries used as energy storage devices. Batteries operation with such current fluctuations leads to rapid degradation of its characteristics as well as a reduction in its lifetime. Furthermore, it leads to a decrease in the reliability of the power supply system and an increase in the cost of generated electricity. A significant drawback of hybrid systems built according to well-known standard schemes is the inefficient use of the primary renewable energy, which is especially critical for energy systems located geographically in areas with severe climatic conditions. This article proposes a new construction method and an algorithm for controlling the modes of hybrid energy systems based on a dual-circuit energy storage device, which increases their reliability and energy efficiency. The prominent outcomes of operating modes of a hybrid power plant with a high penetration of renewable sources are presented, which proves that the proposed method of construction and the proposed control algorithm provide reliable and efficient control of the power balance of the hybrid power system in all possible operating conditions. In addition, the overall efficiency of the proposed renewable energy system is increased from 28% to 60% compared to standard hybrid power plants

Study of the kinetics of the process of producing pellets from red mud in a hydrogen flow

The reduction kinetics of serial phase transitions of iron oxides during reduction to a metallized state with different modes of technical hydrogen supply has been studied and substantiated. The results of the pellets formation when 3-5 % molasses is added to the red mud as a binding reagent are presented. The dependences of the reduction rate of iron oxides on the hydrogen flow rate are obtained. Based on the results of the experiments, a kinetic model was constructed, and with the help of X-ray phase and spectral analysis, it was proved that the agglomerates formed after heat treatment received high strength due to the adhesion of reduced iron particles with red mud particles. The use of a new type of charge materials in melting units will reduce the amount of emissions and dust fractions, as well as increase the metal yield

THE ASYMPTOTIC ANALYSIS OF SOME STOCHASTIC SYSTEMS

The limiting theoremas have been received for the moments of reaching the high level (with elaluation of the degree of convergence) for the controllable random walksAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Dynamics non-stationary problems of envelopes, interacting with inertialmedium

Cylindrical envelopes are investigated in the paper aiming at the calculation method development for cylindrical envelopes, interacting with an internal medium under the action of movable and immovable non-stationary loadings. As a result analysis mathematical methods of transfer processes and cylindrical envelopes of finite and infinite lenght, interacting with an internal medium with the account of the mechanism of the envelope and basis interaction has been developed. Standard solutions of problems of the class considered, with may be used on the stage of the design of underzone cylindrical constructions with the non-stationary interaction with the ground massif have been obtainedAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

RELATIONS OF TRANSFER IN THE THEORY OF MULTIPLY SCATTERING OF WAVES

The derivation of generalized matrix relations of transfer for a wave field in a three-dimensional heterogeneous medium has been represented in the paper as well as the derivation of a system of matrix recurrent equations, the derivations of the invariance principle of Ambartsumian in the finite and differential form from a system of matrix recurrent equations. An integral of a system of recurrent equations has been obtainedAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Influence of phase transformation in solid solutions on the basis of aluminium upon internal friction characteristics

The work covers the investigation of influence of phase transformations and structural changes upon internal friction characteristics of Al-Mg and Al-Cu alloys. It was ascertained that increase of doping component concentration in single-phase solid solutions leads to the increase of the second critical amplitude of internal friction. Characteristic of amplitude-dependable internal friction depends essentially upon the presence of intergranular boundary poprosity in the alloy, and microplastic predeformation causes non-monotonic variation of damping factor and of internal friction rateAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

QUALITY INCREASE OF MESSAGE DELIVERY BY EXCESS CODING MEANS IN TRANSPORT LEVEL OF INFORMATION-COMPUTER NETWORKS (ICN) OF DISTRIBUTED COMPUTER-AIDED SYSTEM (CAS)

The work is concerned with the methods of increasing quality of the message delivery in the distributed CAS networks. The aim is to develop the excess coding method in transport level of ICN with package switching; this method provides the message delay decrease at sufficient simplification of the technical realization. The method of excess coding in transport level using the two-staged binary code (VL-code), at decoding with detection of the errors in the first stage and with correction of the errors in the second one has been developed; the prize of applying VL-codes in the reliable and non-reliable channels has been substantiated theoretically. The algorithms for realization of the proposed excess coding method have been realized, the computing efficiency evaluations have been obtained, and the comparison of the existing and supposed methods has been performed; the program implementation of the of the proposed method by a personal computer IBM PC A-286 has been performed. The algorithm for realization of the excess coding methods on base of the VL-codes have been introduced into the laboratory practice of the Computer Processing and Control Systems Faculty of the St. Petersburg State Elektrotechnical UniversityAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Immunochemical methods of evaluation in selection of cotton species immune to fusarium wilt

The object of investigation is substantiation of the new immunochemical methods of assessing the fungus changeability and immunity of plants. The researchers have revealed the possibility of using the "protein-to-protein" test method in assessing fungus clones and immunity of species, which is of importance in the sphere of selection. The researchers have disclosed differences in the fungus populations existing in Egypt and new methods of improving the stability of specific species. The obtained investigation results may find application in the sphere of selection based on the "immunity" principleAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio