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This paper evaluates various aspects of flexibility in power systems worldwide within the multi-country study framework of IEA Wind Task 25, including grid components and actions which have been favoured for enhancing flexibility in different areas/countries/regions, and how TSOs/ISOs/ utilities intend to manage variable generation in their operating strategies. One methodology to evaluate the diversity of flexibility sources is a "flexibility chart”, which can illustrate several flexibility parameters (e.g. hydro, CCGT, CHP, interconnection) in a polygonal radar (spider) chart.

We have investigated the influence of atomic hydrogen (H) and antimony (Sb) supplied during growth on the deep-levels in GaInNAs pin structure using deep-level transient spectroscopy (DLTS). A dominant transient signal, which corresponds to an electron trap 0.21 – 0.26 eV below the conduction band edge, is observed around 150 – 170 K in all samples. It is found that supply of atomic H during GaInNAs growth reduces these trap density from 4.5×1015 to 3.4×1015 cm-3. Moreover, addition of Sb reveals it also effective for reduction of this trap; the trap density in GaInNAsSb (9.1×1013 cm-3) is 5 times lower than that in Sb-free GaInNAs (4.3×1014 cm-3). According to previous reports, observed electron trap may be connected with a nitrogen-split interstitial defect (N-N)spl. Quantum efficiency characteristics is also improved with atomic H or Sb irradiation. Therfore, we believe that a reduction of trap density by atomic H or Sb irradiation is partly responsible for the improvement of solar cell performance, since such a trap acts as an effective trap center and inhibits minority carrier transport. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 946-949

This article addresses the problem that fluctuations in the torque of an internal combustion engine (ICE) lead to additional energy losses, as it causes fluctuations in the speed and kinetic energy of the car. These losses increase as the frequency of oscillations of the torque of the internal combustion engine approaches the frequency of free (natural oscillations) of the running gear of the car in the longitudinal direction. If there is an elastic connection between the traction force and the movement of the car, the movement of the latter can be represented as complex. At the same time, the portable movement is uniform, and the relative movement is oscillatory. This article presents the results of the study of these losses for cars with mechanical and combined electromechanical drive wheels. Analytical expressions are obtained, which allows to take into account additional energy losses including the tangential rigidity of the tire and the rigidity of the suspension in the longitudinal direction. When using a combined electromechanical drive of the drive wheels as well as in the case of a mechanical transmission of a car, the resonance is dangerous. But with the increase in the share of torque kem on the wheel generated by the electric motor, the relative additional energy losses for the movement of the car are reduced.

The main parameters of the microclimate of pig farms are regulated by the norms of technological design. Naturally, such micro-climate parameters at real energy prices require high costs, but these are the most favourable conditions for the life of suckling piglets. According to the presented analysis, the problem of research is the need to provide a micro-climate in the room for comfortable keeping of pigs, which is currently achieved through high energy. The purpose of the development is to increase the efficiency of the microclimate of pig farms by using a mechatronic control system, rational use of utilized air energy and soil thermal potential with reduced energy costs of the ventilation system. The problem is solved by creating such a mechatronic system to ensure the microclimate of pig farms, which can: switch the direction of airflow to ensure the operation of the system in winter and summer; to control the movement of air, which must be disposed of according to the parameters of its quality; to provide a local microclimate in each place where animals are kept; rational use of soil thermal energy as a source of alternative energy; to carry out automatic pumping of the water necessary for humidification of air, and its utilization. The article presents the results of research of parameters of the developed mechatronic system of providing microclimate of pig premises, which were carried out in three stages: research of heat exchanger of side-evaporating type; substantiation of the ventilation system of polluted air intake; substantiation of the ventilation system for injecting clean air taking into account it's geothermal heating/cooling. The advantage of the proposed mechatronic system of the microclimate of pig farms is that it allows increasing the efficiency of microclimate by rational use of energy of utilized air (due to the use of side-evaporator type heat exchanger based on Maisotsenko cycle) and soil heat potential (geothermal energy) at low operating costs of the ventilation system through the additional provision of mechatronic elements. The presented results of numerical simulation of the indirect evaporative heat exchanger allow us to state that the cooling effect obtained in indirect evaporative channels can be quite high in comparison with traditional air conditioning patterns. The presented heat exchanger based on the Maisotsenko cycle (M-cycle) of considered heat carrier flow scheme is characterized by its high cost-effectiveness, low specific cost, small operational costs and structural simplicity, which is confirmed in the works. The models obtained in the Star CCM +software package can be used for optimization analysis of air-cooling with variations in the Reynolds number, humidity, channel length and geometric dimensions of channels. Because of analytical investigations of the contaminated air intake ventilation system, the method was developed and on its basis – the algorithm was implemented for the determination of geometrical arrangement of holes in the air duct of the mechatronic system for pigsty microclimate maintenance.

To forecast the photovoltaic (PV) power production, global horizontal irradiance (GHI) obtained from a numerical weather prediction (NWP) model are useful. In Japan, the Japan meteorological Agency (JMA) has been developed an operational NWP (that is, meso-scale model, MSM) with the horizontal grid spacing of 5km. In this study, the range of forecast errors of the GHI is investigated on seasonal and annual changes. In addition, we compared forecast errors between a station and a relatively large area of the Kanto region in the main island, Japan. Validation results of hourly GHI forecasts showed that overestimations of GHI forecasts were found in relatively higher clear sky conditions while underestimations of those were found in relatively lower clear sky conditions. In clear sky or rainy conditions, ranges of forecast errors tend to be relatively smaller, suggesting that the GHI values are well forecasted in these conditions. Seasonal analysis of the range of forecast errors showed that underestimations of the GHI were significant in summer at a point station. From results for a relatively large area of the TEPCO (Tokyo Electric Power Company) region, we confirmed that ranges of forecast errors tended to be decreased by a spatial- smoothing effect. 28th European Photovoltaic Solar Energy Conference and Exhibition; 3638-3643

The relevance of this study is to solve the basic task for society to ensure sustainable management by improving the spatial management system of natural resource assets, increase their usage efficiency and ensure sustainable socio-economic development of Ukraine on this basis. At all levels of the state government, there appeared a need to ensure spatial management and transform the organizational structure of natural resource management on the basis of the introduction of a modern system of territorial natural entities with the change of relevant functions, mechanisms and powers in the direction of increasing the ecological and economic effect in various spheres of economic activity. Aim of the research: identification of the highest priority, to ensure sustainable management in resource constraints, the composition of threats and risks and their grouping; development of a closed scheme of permanent clarification of the most important, for spatial sustainable development, threats and risks. The methodological basis of the study is the work of domestic and foreign scientists on spatial management of natural resources, sustainable spatial development and economic security, regulations, analytical and statistical materials of ministries and departments, international organizations, other scientific and information materials. The study involves the use of a number of interrelated methods, including methods: analysis and synthesis; system analysis; economic and mathematical; expert assessments; graphic, etc. The scheme of grouping of organizational and economic mechanisms of realization of spatial model of management of sustainable management within a certain state formation is constructed. According to which a universal, for three stages of implementation of the corresponding type of macro- model (initiation, consolidation, incorporation) spatial management of sustainable development, algorithm is developed. The use of the latter involves: continuous grouping and identification of the most significant threats and risks (in a closed cycle of management, organizational and economic, forecasting, analytical and econometric procedures); development of measures to eliminate the consequences of turbulent shifts.

Subsynchronous oscillation (SSO) usually caused by series compensation, power system stabilizer (PSS), high voltage direct current transmission (HVDC) and other power electronic equipment, which will affect the safe operation of generator shafting even the system. It is very important to identify the modal parameters of SSO to take effective control strategies as well. Since the identification accuracy of traditional methods are not high enough, the stochastic subspace identification (SSI) method is proposed to improve the identification accuracy of subsynchronous oscillation modal. The stochastic subspace identification method was compared with the other two methods on subsynchronous oscillation IEEE benchmark model and Xiang-Shang HVDC system model, the simulation results show that the stochastic subspace identification method has the advantages of high identification precision, high operation efficiency and strong ability of anti-noise.

Peer-reviewed journal article Applied Rheology