The development of the national wind power industry in Ukraine faces a number of problems because of the lack of sufficient information on the peculiarities of the operating modes of wind farms under real-life conditions. This applies to wind load indices in different regions, estimates of the performance of wind power plants with different types of wind turbines. One of the important characteristics of the potential capabilities of a wind power plant in the grid is the time and rate of utilization of installed capacity (installed capacity utilization factor -ICUF), which are widely used in the design of power plants. The paper presents the results of calculating the characteristics of the production potential of wind power plants with generators of different types and capacities, which are defined in terms of time and coefficient of utilization of the installed capacity. It is shown that such characteristics of the wind power station uniquely characterize the efficiency of the application of a specific wind generator in real conditions for use in design calculations.Keywords: wind turbine; wind station; time of use of installed capacity; coefficient of utilization of installed capacity. Definition of a scientific problemThe current state of the world renewable energy is characterized by high dynamics of development. Significant features of this are many confirmed facts. In recent years, increased participation of renewable sources in the balance of electricity generation in the world's electricity systems continues. [1]. On 21 04 2017 a national energy company in the UK said that it can confirm that for the past 24 hours it supplied GB's electricity demand without the need for coal generation [2]. It happened for the first time since 1880. A similar situation occurs periodically in other countries. The State Energy Operator of the People's Republic of China said that according to the results of 2016, an indicator of 150 GW of power at wind farms was reached [3]. In addition, it should be noted the results of research on the prospects for the development of renewable energy in 139 countries [4] on the model of the world's energy, proving the possibility to transition to exclusively renewable energy sources by 2050. The above facts confirm once again that alternative renewable power, in particular wind energy, loses its alternating nature and becomes an important basic component of world electricity generation at the level of coal, atomic and oil and gas energy.Wind and generally renewable energy in Ukraine is developing at a different pace, which is primarily due to the effects of crisis phenomena. In 2016, the installed capacity of Ukrainian wind farms amounted to 525 MW in the production of 925 thousand MWh and the share of 49 % of the capacity of alternative and renewable sources [5]. The need for wind energy development in Ukraine is determined by the need to reduce the dependence on traditional types of fuel and its imports, reducing harmful emissions into the atmosphere, which can be solved by the ...
The use of extra-high voltage networks leads to a number of problems with compensation for excess reactive power. An option to avoid these problems is to apply asynchronized synchronous turbine generators, which have a number of advantages over traditional synchronous generators. These advantages are largely manifested under conditions of generator operation in power grids with excess reactive power. Typical examples of such power grids are power grid "Burshtyn Island" and "Power bridge "Ukraine-EU". The article presents the results of mathematical modelling of the steady-state modes for "Power bridge "Ukraine-EU". The mode coordinates are determined under different conditions regarding reactive power particularly with using an asynchronized turbine generator in asynchronous as well as asynchronized modes. The results obtained prove the feasibility and effectiveness of the proposed technical solution.
Nach nur einem Jahr im Amt hat Präsident Janukowytsch eine ungeheure Machtfülle auf sich vereint, mit der ein Übergang zu einem autoritären Staat jederzeit möglich ist. Die Korruption wird vor allem verbal bekämpft und dieser Kampf dazu benutzt, den politischen Gegner in Schach zu halten. Die Pressefreiheit existiert eher formal und muss von den Journalisten und der Gesellschaft verteidigt werden. Der Staat ist stabil, doch wirkliche Reformen sind nicht in Sicht. Die Ukraine nähert sich immer mehr einer »imitierten Demokratie« an-einem Phänomen, das wir bereits aus Russland kennen.
The object of research is the efficiency of exposure to electromagnetic field (EMF) of ultra-low intensity on biological objects, which is formed by a generator of broadband radiation. The principle of action of the generator is based on formation of electromagnetic radiation induced by periodic pulsed gas discharge in coaxial system of electrodes, which is loaded on a dielectric rod antenna. The method of selection of signals and corresponding equipment, which energy characteristics of radiation correspond to the criterion of non-thermal influence on bioobjects, is developed for obtaining a comparative assessment of influence bioefficiency. The proposed new method for processing experimental data using statistical calculations that meet the requirements for the processing and interpretation of the results. The seeds of wheat and interaction of millimeter range electromagnetic oscillations with bone marrow cells of rats were used as biological objects for investigating the effect of millimeter range electromagnetic oscillations. A biosensory effect was obtained when exposed to broadband radiation of ultra-low intensity, compared to the control sample. A change in the properties of the seeds, in particular, heat resistance, is observed. According to the experimental data, seeds turn out to be less susceptible to heat as a result of their pretreatment with EMF. The biological response is observed to depend on the frequency and time of irradiation. Also, the dependence of the decrease in the number of dead cells on the time of EMF irradiation was experimentally proved. The equation of dependence of selective average proportion of dead cells in rat bone marrow on irradiation time was calculated. Biosensory effect of exposure to broadband ultra-low intensity EMF of the developed emitter was revealed. It was established and statistically proved that the minimum time with the maximum positive effect of exposure to electromagnetic radiation of millimeter range on bone marrow cells of rats is 30 minutes, compared with an unirradiated sample. The results make it possible to evaluate the positive effect of electromagnetic oscillations on biological objects and propose the results of studies for practical use in the development of medical systems.
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