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Tariffs for energy and energy resources are the main factors determining the sustainable development of the economy. The aim of the paper is to determine and compare the dynamics evolution of the tariffs for thermal energy and the evolution of the gross domestic product (GDP).The data on the heat consumption and tariff change in the city of Chisinau were examined in monetary terms and in relative units compared to the base year 2009. The higher the tariffs, the more part of the GDP, characterized in the economy by the volume of "Output", is spent on "Intermediate consumption (PP)". The difference between "Output" and "Intermediate consumption" volumes is the "gross added value (VAB)", which is the main component of GDP. The analysis of the changes in the real GDP volume of the Republic of Moldova and the increase of the tariffs for the years 2009-2017 (taking into account the GDP forecast for 2018) show that the increase in the tariffs for thermal energy significantly exceeded the real GDP growth. Considering that the planned GDP growth is 4,7% and taking into account the change in the consumer price index (inflation rate), the calculated reduction of the thermal energy tariff in Chisinau is estimated at 28% compared to the existing value, so to 803 lei / Gcal compared to the currently regulated value of 1122 lei / Gcal. The conclusion was reached on the opportunity of applying the proposed methodology to justify current tariffs and in the near future not only extends to thermal energy tariffs, but also for other types of energy, material resources and services in the field of production and social sphere.

The purpose of this research is to determine the effective way of implementation of the control algorithm, as an important functional part of information and control computer systems. The search criterion is the minimum of internal hardware FPGA resources required for the control unit implementation. This criterion allows miniaturization of dimensions, improves reliability by reducing the number of interconnections inside the chip, and ensures the possibility of a compact arrangement of various system components, which is especially important when using the “system-on-chip” design technology. The control unit holds a prominent place in the digital information and control systems. A comparative analysis of two control unit models represented as a finite state machine with either hard or programmable logic was proposed. Advantages and disadvantages of both models were determined according to the peculiarities of the information and control system algorithms, and, it was proved that the FSM model with a programmable logic matched these peculiarities in a greater degree. The purpose of this study was achieved due to the application of the proposed method for the implementation of the FSM with the programmable logic using the embedded memory of the FPGA and ProASIC chips. The main result was a substantial decrease in the LUT number used. The experimental results were obtained applying the chips of the world's top manufacturers - Xilinx, Altera/Intel, Microsemi. The studies were carried out based on the onboard computing complex control algorithm.

The structure of the economy of the Republic of Moldova was reviewed and the analysis of the main macroeconomic indicators, including the energy sector, was conducted. For a long period, data on the state of Moldova’s energy, technical and economic indicators and development trends have been analyzed. Particular attention is paid to the definition of changes in the value of the real gross domestic product (GDP), taking into account the coefficient of deflation. The quantitative dependence of GDP on the volumes of "Output" and "Intermediate Consumption" is shown. It is revealed that the more “Intermediate Consumption”, the lower the GDP, ceteris paribus. The major share of the cost of the industry sector is covered by “Intermediate Consumption”, which in turn is higher, the higher the tariffs for energy, materials and other services provided by the industries to each other. It was concluded that tariff growth should not overtake real GDP growth over the past few years. The results of the calculations and their analysis show that, in reality, the growth of tariffs is far ahead of the growth of real GDP, which does not contribute to the stable development of the country's economy. It was proposed to revise tariffs, in particular for energy resources, and to bring the rates of their change in line with the growth rates of real GDP. An approach has been formulated for determining the marginal levels of tariffs, based on the condition that their growth rates do not exceed the growth rates of real GDP.

Consider the propagation of electromagnetic energy through multiconductor three-phase high-voltage transmission line with arbitrary number of conductors. The mathematical formulation of the problem represents the system of partial differential equations known as transmission line equations. When constructing the capacitance matrix of an electric line, it is necessary to solve the boundary problems for the Laplace equation with nonlocal boundary conditions. The aim of this research is to develop a new method for constructing a potential coefficients matrix, which allows us to express the voltage vector in the wires through the charge vector. The application of this method leads to the necessity of solving a boundary value problem for Laplace equations with nonlocal boundary conditions. A new type of non-local boundary conditions has been identified, which has not been previously investigated. The boundary conditions of this type are represented by the contour integral over the boundary of the region from an unknown potential. In the general case, the obtained problem does not have a unique solution. The theorem of existence and uniqueness of the solution for the boundary value problem for the Laplace equation with nonlocal boundary conditions is proved. However, the requirement that the potential on the wire surface is constant allows us to prove the existence and uniqueness of the solution for considered problem. In order to illustrate the application of the developed approach we have solved numerically the problem for the sector-shaped cable with three cores. The values of potential and capacitive coefficients obtained by calculation are given. The error of the values of the diagonal elements of the matrices of potential and capacitive coefficients is estimated as less than 0.1%.

The purpose of this paper is to estimate the possibility of technical use of the 110 kV voltage lines (OPL) for the interconnection of the power systems of the Republic of Moldova and Romania, taking into account in the unified power system regime, which includes the power system of the CIS countries, of Moldova, Romania, Ukraine and other countries in the region. In the calculation scheme of the permanent synchronous regime of the integrated system, the interconnection zone of the Moldovan and Romanian systems was highlighted for the lines of 110 kV: Stanca-Costeşti, Ţuţora (Fai) - Ungheni and Hushi-Cioara. Transformer phase difference angle adjustment devices have been introduced in the 110 kV OPL to provide the bidirectional power shift regime. In the existing topology of electricity networks, power flows at the power system interface are directed from the Republic of Moldova to Romania. Changing the direction of the power flows is possible through the 110 kV OPL A when equipped with phase shift devices. The results of the calculations of the permanent regime have demonstrated the possibility of achieving the reciprocal power exchange regime between the interconnected power systems by adjusting the phase difference angle. It was shown the possibility of stable operation when using 110 kV overhead power lines as interconnection lines of the Moldovan and Romanian power systems. The issue of interconnection through the 110 kV lines is complex and requires an individual approach to how to achieve it.

The object of the study is a frequency converter based on IPC technology. The purpose of the study is to determine the device's performance characteristics by means of a mathematical apparatus describing the area of existence of operating modes for active and reactive power. On the basis of combinatorial laws, variants of non-repeating states of thyristor keys were obtained. The initial phases of active and reactive power components are determined by varying in accordance with the cosine law with two non-repeating combinations of key switching on each pair of conjugate reactive elements. The input of two constants made it possible to simplify the arguments influencing the magnitude and direction of the transmitted power by the device. A comparative analysis of the regime parameters and the characteristics obtained with the help of the simulation model and calculated by the proposed method confirms the identity of the results. The error of the method fluctuates between 0.5% and 1.5%. The developed method made it possible to determine a number of unique variants of the transmitted power level when adjusting the angle \(\delta_{sr}\) in the range from 0º \(\div\)360º . This allows to adjust the magnitude and direction of the transmitted power when "sliding" or slow and arbitrary frequency changes. Thus, the proposed method made it possible to determine with a high degree of accuracy the domain of existence of the regime parameters with the construction of switching diagrams of keys to maintain an ordered unidirectional power flow with frequency matching by the device under study.

The purpose of this work is to develop a diagram version of the compensating device, and its control strategies using a phase-shifting transformer device. The purpose has been achieved performing a complex of research based on structural-simulation models both for the compensating device as a whole, and for the phase-shifting transformer. Based on the phase-shifting transformer model, calculation experiments in idle, short-circuit and under load conditions have been carried out. The obtained data allowed to determine the energy characteristics of the object of research and to perform analysis of its characteristics during the process of adjusting the angle of phase shift. The paper also provides the results of research in the regime's parameters issue of the device as a whole. The obtained data confirmed the functionality of the proposed reactive power source. The novelty of the work consists in the development of innovative circuit variant of controlled compensating device. Its component parts are susceptances, allowing carrying out a symmetrical adjustment of reactive power both consumed and offered to the network in a predetermined range. A control diagram for adjusting windings of a phase-shifting transformer has been proposed. The control's principle of power electronic keys provides control of the phase shift of the voltage at the output terminals of the device in the range from 0° to 60° at 15 switching positions. The proposed technical solution provides symmetrical smooth control of reactive power in a wide range at the point of connection of the device to the network.

Основной целью текста был анализ избранных вопросов, связанных с польской энергетической политикой в институционально-правовом аспекте. Анализ был сосредоточен главным образом на: (1) правовой основе энергетической политики, (2) основных субъектах энергетической политики, (3) прогнозах и сценариях энергетической политики. Представленный анализ не охватил всех вопросов, связанных с нормативными актами, касающимися польской энергетической политики, поэтому, для уточнения проблемы исследований в тексте представлены следующие исследовательские вопросы, которые связаны с выводам: (1) В какой степени правовые решения влияют на эффективность проведения энергетической политики в Польше? (2) Какой из принятых сценариев развития энергетики, в планировочной документации энергетической политики Польши, следует считать наиболее вероятным? 1. ВЫВОДЫ Следует отметить, что необходима бóльшая специализация министра энергетики в области подготавливаемых целей и направлений, содержащихся в документах по планированию, т.е. в отдельных проектах энергетической политики. Кроме того, целесообразным представляется активизация усилий, которые будут воздействовать на бóльшую согласованность в политических и институциональных действиях, а также на согласованность между отдельными документами, которые прямо или косвенно связаны с энергетической политикой. Следует отметить, что необходимо изменение правовой основы ведения энергетической политики министром энергетики, поскольку текущие законодательные нормы кажутся недостаточными и малоэффективными с точки зрения определения стратегических целей и их осуществления в энергетической сфере. Например, одной из проблем при проведении энергетической политики является связывающая сила документации, утверждаемой Советом министров. Следствием вышесказанного является отсутствие согласованного видения и скоординированных действий в области энергетической политики. Следует положительно оценить изменения в области консолидации вопросов, касающихся энергетики в отдельно взятом министерстве, т.е. Министерстве энергетики. В связи с необходимостью повышения эффективности работы Министерства энергетики следует произвести дальнейшую консолидацию отделов, которые связаны с энергетикой, например, связанных с возобновляемыми источниками энергии, будучи в компетенции Министерства Охраны окружающей среды. 2. ВЫВОДЫ Стоит обратить внимание, что на осуществление определенных сценариев развития энергетики в Польше будет влиять много факторов. К основным факторам, детерминирующим изменения, следует причислить структурно-экономические факторы и факторы политического риска. Достаточно большое значение будут иметь факторы, принадлежащие ко второй группе, т.е. факторы политического риска, что следует из факта инструментального отношения к энергетической политике и энергетической экономке с целью внутренней политики, т.е. партийного и парламентарного соперничества. Из этого возникает предположение, что политические факторы будут устранять какие-либо радикальные решения в отношении направлений и целей энергетической политики. При анализе долгосрочных прогнозов, следует также учитывать изменения в действиях властей в Польше и динамику изменений в области энергетической политики в Европейском Союзе. Проводя сравнительный анализ трех сценариев развития энергетики (сбалансированный сценарий, ядерный сценарий, сценарий на основе развития сектора ВИЭ и газового сектора «газ+ ВИЭ»), представленных в проекте «Энергетическая политика Польши до 2050 года», следует отметить, что наиболее радикальные решения будут наименее реалистичными в осуществлении. Следовательно, в первую очередь, следует исключить более широкое участие Польши в развитии ядерной энергетики, хотя с этими допущениями следует учитывать значение факторов, представленных в тексте. Следует принять, что наиболее реальным является сбалансированный сценарий с медленным темпом изменений в секторе возобновляемых источников энергии, газовом и ядерном секторах. Следует подчеркнуть, что эти предположения могут измениться в связи с возможностью принятия политического риска со стороны власть имущих. Следует признать, что наибольшее влияние на замедление развития, например, возобновляемых источников энергии в Польше, имеют политические действия или партийное и парламентское соперничество, отсутствие мышления политиков в категориях национальных интересов и отсутствие мышления политиков в категориях долгосрочной стратегии, которая превышала бы период парламентского срока полномочий. The analysis scope in the text encompasses selected problems of Poland’s energy policy. The analysis of Poland’s energy policy embraces only pivotal institutional and legal issues, among which the following has been reckoned: (1) the legal basis and the statutory scope of the energy policy, (2) the objective scope of energy policy, (3) the forecasting scope of the energy policy. For the research problem addressed in the text to be elaborated, the following research questions have been presented: (1) To what extent do legal solutions affect the effectiveness of the energy policy pursued in Poland?, (2) Which one of the scenarios for the development of the energy industry, adopted in the planning documents concerned with Poland’s energy policy, should be considered most likely? The approach to the issue at hand is of an overview character, and hence the presented analysis is chiefly based on the elaboration and synthetic presentation of selected institutional and legal issues, which have been supplemented with the author’s own conclusions. Besides, the text features a comparative analysis of the three scenarios for the development of the Polish energy industry, contained in the Draft Energy Policy Until 2050 of 2015. Объем анализа в тексте охватывает избранные проблемы энергетической политики Польши. Анализ энергетической политики Польши охватил только узловые институционально-правовые проблемы, которые включили в себя следующие вопросы: (1) правовые основы и предусмотренная законом область энергетической политики, (2) субъективная сфера энергетической политики, (3) сфера прогнозирования энергетической политики. Для более подробного исследования проблемы, рассмотренной в тексте, представлены следующие исследовательские вопросы: (1) В каком объеме юридические решения влияют на эффективность проведения энергетической политики в Польше? (2) Какой из принятых сценариев развития энергетики в планировочных документах проекта энергетической политики Польши следует считать наиболее вероятным? Подход к проблеме имеет наглядный характер, отсюда представленный анализ базируется в основном на разработке и синтетическом представлении избранных институционально- правовых вопросов, которые были дополнены собственными выводами. Кроме того, в тексте был проведен сравнительный анализ трех сценариев развития польской энергетики, содержащихся в «Проекте энергетической политики до 2050 г.» с 2015 года. 2 61 76 International and Security Studies

The aim of this article is to determine the impact of the energy factors on the US foreign policy. The article raises the issues of the modern energy system and energy security. The author demonstrates how the control over energy resources ensures the US political befefits. ; Цель настоящей работы заключается в определении влияния энергетических факторов на внешнюю политику США. В рамках материала описывается современная энергетическая система и энергетическая составляющая безопасности. Показано как контроль над энергетикой дает США политические преимущества.

The paper presents deal with the heat pump designed mainly for heat supply systems using the qualitative law of regulation of the heat supply mode (constant flow rate of the heat carrier). For this purpose, an air-to-water heat pump with carbon dioxide as a refrigerant and compressor driven be gas piston unit is used. The aim of the work is to develop a scheme in which the position of the operating point of the heat pump compressor does not depend on fluctuations in the refrigerant flow rate, as well as using the heat produced by the gas engine - driven by the heat pump compressor. This goal achieves by elaboration of internal heat exchangers with an adjustable heat exchange surface area. The heat exchange surface area regulates by installing of an intermediate heat-conducting cylindrical element between the refrigerant and thermal agent circuits. The intermediate cylindrical element moved by using, for example, an electric stepper drive. The conditions, under which the sleeve can be considered as a thermally thin body. To increase the COP of the heat pump (HP), the additional heat exchanger, installed at the outlet of the ejector used in the pump has been used. It is. In the heat exchanger, the working fluid has been heated by using the waste heat of the gas piston unit (GPU. It had been shown that in the temperature control loop the PI controller may be used, and to compensate for the flow rate pulsations, it is necessary to use a combined control system.