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Принятие комплекса законодательных актов в сфере энергетики, объединяемых термином Energiewende , существенно изменило структуру потребления энергии в Германии: в настоящее время наи-большую долю в ней занимает зеленая энергия, выработанная за счет использования ветра, солнца, воды и биомассы. Подобные изменения, безусловно, можно расценивать как успех. Однако, одновременно с целена-правленным изменением структуры производства и потребления энергии в Германии возникли определенные социально-политические, экономические и юридические проблемы, требующие тщательного изучения. Дискус-сионным является вопрос о соответствии целей и предлагаемых мер их достижения, в частности, в отношении бесперебойности энергообеспечения, расширения электрических сетей, совершенствования подхода к ценооб-разованию, экологических последствий с учетом курса на тотальное расширение производства энергии за счет возобновляемых источников. Актуальными для Германии и затрагивающими энергетическую политику России являются вопросы ускоренного сворачивания ядерной энергетики и легитимности национального курса Герма-нии на продвижение зеленой энергетики в контексте интеграции с Европейским энергетическим рынком. В статье выполнен анализ указанного комплекса проблем и охарактеризована роль национального законода-тельства Германии в их решении. from wind, solar, water and biomass now provides the largest contribution to the total electricity consumption. In this respect, Energiewende can be regarded as an overall success. But in parallel to this scenario, a critical discourse has evolved concerning socio-political, economic and legal issues. The congruence of objectives and measures for example, in regards to ensuring security of supply, expansion of electricity networks, development of electricity price and envi-ronmental consequences in the course of expansion of electricity generation from renewable sources is the main focus of socio-political and economic discussions. Accelerated phase-out of nuclear energy and constitutional disputes regarding the legality of national orientation of the promotional scheme for green electricity in respect to the integration of German electricity sector in the European internal market for energy are in the centre of the debate and have a remarkable impact on the energy policy in Russia as well. Against this background, present article examines the con-tribution of German Energiewende to the resolution of complex challenges of the developed industrial society. №4 (226) (2017)

The work is devoted to the study of heat transfer in channels with a longitudinal pressure gradient. The aim of the work is to develop methods for increasing the heat transfer intensity in channels with a longitudinal pressure gradient. The goal was achieved by developing the original design of the surface intensifier, made in the form of a horseshoe-shaped dimples, as well as by conducting heat transfer studies in the channel with a longitudinal pressure gradient and dimples of various geometries and locations. It was found that a numerical solution using the k-epsilon turbulence model shows not sufficiently stable results, including the values of local heat transfer coefficients can exceed 2 ... 2.5 times their actual values for a single dimple. Moreover, the use of the k-w-sst turbulence model shows more stable results. The most significant results obtained in the work are as follows: it was revealed that the use of holes, their geometry and location have a significant effect on the heat transfer intensity in a channel with a longitudinal pressure gradient; the design of the original horseshoe-shaped dimples has been developed, the use of which allows to intensify heat transfer by 13 ... 47% depending on the Reynolds number when they are arranged in three rows in the corridor order compared to staggered hemispherical dimples; when comparing the efficiency of using the developed dimples with hemispherical holes installed in three rows in the corridor order, the heat transfer increased by 21 ... 51% when the Reynolds number changed from 3000 to 15000.

The purpose of this work is the theoretical substantiation and development of a practical method for calculating the exchange fund of electrical equipment of an industrial enterprise. The purpose is achieved through the use of separate methods of queuing theory if the flow of applications for repairs and restoration are the simplest. It is confirmed by the results of statistical studies. Therefore, for the mathematical description of the repair problem the authors use the scheme [Mm; Ms; n], which corresponds to the process of death and reproduction. As a criterion for optimizing the exchange fund of electrical equipment it is proposed to use the zero probability waiting for the replacement of a faulty electrical component with a working from the exchange fund. For the case of the simplest flow of applications for service, the authors suggest to use the Peck and Hazelwood tables, which significantly simplify the calculation of the exchange fund for known failure rates and electrical equipment recoveries. For practical use of the proposed method, the authors have developed convenient forms for presenting initial data for calculating the exchange fund, and it is proposed to present the results of calculations in the form of several options for the optimal number of electrical equipment in the exchange fund depending on the accepted level of zero expectation probability, the number of elements from the exchange fund and their recovery time. The proposed method will optimize the exchange fund of electrical equipment and reduce the cost of its formation.

In this paper, we consider the problems related to measuring and analyzing the characteristics of partial discharges which are the main instrument for oil-filled high-voltage electrical equipment diagnosing. The experiments on recording of partial discharges in transformer oil have been carried out in the “point-plane” electrode system at alternating current. The instantaneous voltage and the apparent charge have been measured depending on the root-mean-square voltage and the phase angle of partial discharges. This paper aimes at carrying out a statistical analysis of the obtained experimental results, in particular, the construction of a parametric probabilistic model of the dependence of the partial discharge inception voltage distribution on the value of the root-mean-square voltage. It differs from usual discharges which occur in liquid dielectric materials in case of sharp inhomogeneous electrode system. It has been suggested that discharges of a different type are the discharges in gas bubbles that occur when partial discharges in a liquid emerge. This assumption is confirmed by the fact that the number of such discharges increases with increasing the root-meansquare voltage value. It is the main novelty of this paper. This corresponds to the nature of the occurrence of such discharges. After rejecting the observations corresponding to discharges in gas bubbles, a parametric probabilistic model has been constructed. The model obtained makes it possible to determine the probability of partial discharge occurrence in a liquid at a given value of the instantaneous voltage depending on the root-mean-square voltage. 

In 2011-2012 The parity of the cost of energy of thermal power plants on fossil fuels and the cost of energy from wind farms and solar power stations had come. Since 2017, the capacities of introduced renewable energy sources in the world have exceeded the volumes of commissioned capacities of traditional energy. The transition from traditional energy technologies to renewable energy sources (RES), which are becoming more profitable from an economic point of view and can minimize the negative impact of energy on the environment, is being phased. This article gives a review of the prospects of application of the combined schemes using renewable energy sources to generate energy. The paper discusses the most important areas of energy development in our country.

The work is d to improving methods for calculating the cooling system of a microturbine with a rotor on air bearings. When designing gas turbines, it is important to integrate gas-dynamic calculations with thermal finite-element calculations. In practice, the conjugation of temperature fields in solids and liquids, as well as the transfer of thermal loads between the media are carried out using several approaches: direct, non-conjugate and sequential coupled. Numerical simulation of the coupled heat transfer in a cavity formed by the gap between the rotor and stator is carried out. To calculate the flow characteristics of a viscous compressible fluid and heat transfer. The degree of influence on the results of the type of turbulence model used, the influence of taking into account the conjugate heat transfer, is studied. The effect of the mass flow rate of the cooler on the flow structure and the cooling efficiency of the walls of the rotor and stator is investigated. A comparison is made with experimental data. Numerical experiments have shown that in typical cases the flow in the cavity is turbulent. The cooling efficiency has a limit on the flow rate of the cooler. The temperature distribution along the length of the rotor has a noticeable minimum in the region of the middle of the length of the rotor. The significance of the obtained results lies in the fact that the choice of the turbulence model weakly affects the calculation results and taking into account the conjugate nature of heat transfer is necessary.

В рамках настоящей работы изучаются простая феноменологическая модель aw-динамо, с динамическим подавлением α-генератора квадратичной формой от компонент магнитного поля. В частности, рассматривается подавление спиральностью и энергией. Определяется форма ядра функционала подавления при которой интегральный член можно устранить и свести модель к системе дифференциальной лоренцевского типа. В общем случае в модели есть возможность широкого варьирования ядра функционала и вида квадратичной формы. В рассматриваемой модели потенциально могут реализовываться значительно более богатый набор динамических режимов, по сравнению с классическимслучаем лоренцевской системы In the framework of this work, we study a simple phenomenological model of a αω — dynamo, with dynamic suppression of a α-generator by a quadratic form from a magnetic field component. In particular, suppression of spiralness and energy is available. The shape of the nucleus is determined, and the system of differentiation of the Lorentz type. In general, the models have the possibility of a wide range of functional and quadratic forms. Compared with the classical case of the Lorentz system.

One of the most important informational components of control systems is the data of the static load characteristics of each transformer of the substation. Currently, the evaluation of real static characteristics of the load is determined generally by the following methods: computational, analytical, passive and active experiments. These methods exhibit significant disadvantages regarding accuracy and cost rating and encounter plenty of parameters that are difficult to formalize (including climatic factors). The purpose of this work is to reduce electric power losses at 110/220 kV substations by implementation of a new control system for power transformers. This goal has been achieved by using a fuzzy controller in the structure of the control system for power transformers of 110/220 kV tie substations. The presented solution is multi-functional and can be extended to a wide class of power facilities. The results of the simulation of the transformer voltage regulation process, performed in the MatLAB application environment, showed that the implementation of a new fuzzy controller structure had improved the efficiency of the substation power control system in forecasting and management (compared to classical solutions based on regression and probabilistic models). Herewith, the most accurate accounting of consumer load, the maximum use of equipment at the substation for voltage regulation at the points of release and a significant reduction of active power losses at the tie substations 110/220 kV (up to 12,12%) compared to already known solutions were observed.