70 milk sugar, organic acids, immune bodies, vitamins, and other substances that need to be preserved during its processing [1]. Obtaining high-quality dairy products is possible under the conditions of compliance with the technological and structural recommendations directly from the moment 1. Introduction Pasteurized milk is one of the types of food that has all the necessary consumer properties for the nation's fullfledged nutrition. In particular, milk contains fats, proteins,
Reducing electricity losses in electrical networks is a complex complex problem that requires significant capital investments necessary for optimizing the development of electrical networks, improving the electricity accounting system, introducing new information technologies in marketing activities and managing network modes, training personnel and equipping them with means of testing measuring devices etc. In reality, in recent years, in connection with the inclusion of normative losses in the tariff for electric energy transmission services, a dangerous trend of adapting these norms to actual losses has emerged. The article analyzes the occurrence of power losses in electrical engineering systems and electrical networks of various voltage classes. Special attention is paid to the so-called excess losses, which are not taken into account during design and operation. These losses occur in insulators, linear fittings, current-limiting reactors, electricity meters, windings of current and voltage transformers, etc. Excessive losses of electricity in electric networks are direct financial losses of electric power companies. Savings from reducing losses could be directed to technical re-equipment of networks; staff salary increase; improvement of the organization of electricity transmission and distribution; increasing the reliability and quality of electricity supply to consumers. Unaccounted losses reach approximately 1% of the total amount. This fact must be taken into account. Because currently we are talking about millions of losses.
The purpose of the work is to study of options for thermal modernization of enclosing structures with a justification of the optimal composition of energy-saving measures to achieve maximum energy efficiency of buildings. Ukraine's energy balance shows that more than 30% of the total energy is consumed by the residential sector, of which up to 80% goes to heating. This is due to the low level of energy efficiency of the enclosing structures of residential buildings, as well as the unsatisfactory technical condition of utilities, due to physical wear and tear and obsolescence. The peculiarities of the influence of the type of thermal insulation materials and their characteristics on the thermal and energy performance of the building are investigated. It was found that the increase in the density of insulation affects the thermal resistance of walls in different ways - the density of mineral wool and extruded polystyrene have the opposite effect of foamed polystyrene, ie insulation of mineral wool or extruded polystyrene should be chosen with the lowest density Element-by-element analysis of the components of enclosing structures proved that their impact differs significantly, in the case of separate implementation of measures can reduce heat consumption by 0.07… 23%, and the priority is to modernize the walls of building facades (provided that the glazing ratio K ≤ 0 , 25). Measures of complex thermal modernization of enclosing structures are substantiated by the method of expert assessments according to technical-energy, financial and ecological criteria. Calculations confirm that the complex thermal modernization will reduce the value of specific energy consumption and specific greenhouse gas emissions by 1.5 times, specific heat consumption - by 1.9 times, increase the energy efficiency class of the building from G to D. It is shown that the normative values of heat transfer resistances of external enclosing structures will provide only the class D energy efficiency of the building. It is not possible to achieve the recommended class "C" and higher by further increasing the thermal resistance of the enclosing structures - it is necessary to modernize the engineering systems of the building.
The assessment of the discharge strength of the insulation is of the utmost importance for the prevention of overlap and the establishment of the deadline for the implementation of preventive measures. Preventive measures used in electric networks to prevent insulator overlap have low efficiency, and existing diagnostic and control tools are not always able to correctly assess the insulating capacity of insulators during operation. The main reasons for overlapping and damage to the insulation are its contamination with various chemical substances, which is also accompanied by moisture. Overlapping of the surface of the insulators leads to single-phase short circuits to the ground or to interphase short circuits. The greatest danger is caused by short-circuits accompanied by an intermittent electric arc, which can cause large overvoltages in the electrical network, and their value reaches 3...3.2Uf. Such conditions, in turn, are very favorable for covering the surfaces of insulators. The non-destructive control method of assessing the insulating capacity of insulators based on the measured values of leakage currents is the most suitable not only for insulators of complete switchgears of 10 kV, but also for external insulation of open switchgears of 35 kV, as it allows continuous automatic control of the degree of contamination of the insulator. The purpose of the research is to establish the functional dependence between the leakage current of the contaminated insulator and its discharge voltage. As a result of theoretical studies of the working conditions of insulation during operation, the characteristics of the surface layer of insulators contaminated in natural conditions were determined, these characteristics were analyzed depending on the location of the substation and the time elapsed since the last cleaning. According to the methods of regression and correlation analysis, based on experimental data, an empirical regression line was constructed, which made it possible to determine the insulator leakage current, which is dangerous from the point of view of overlapping.
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