In view of the stage-by-stage increase of electricity tariffs, further development of metro rolling stock is impossible without application of modern energy saving technologies and energy efficient systems. Purpose. Further development of metro rolling stock equipped with regenerative braking systems with regard to increase in its energy efficiency due to introduction of an on-board energy storage units of capacitance type with account of changes in daily operational condition. Methodology. Three approaches for determination of parameters of on-board capacitive energy storage are suggested based on the results of experimental research studies, and also using the statistical methods of data processing, analysis and probability theory methods. The suggested approaches include successive implementation of the following combined stages: a choice of operation area and a model of metro rolling stock, determination of normal daily operational environment, experimental research on energy power processes during different daily operation of rolling stock, mass-data processing, histograming and determination of on-board capacitive energy storage parameters using the suggested criteria. findings. Energy power processes were registered under normal daily operational conditions of rolling stock equipped with regenerative braking systems on Sviatoshynsko-Brovarska line of PU "Kyiv Metro". Instantaneous and average energy power and an amount of electric power for each regenerative braking process of a train were measured. According to the results of mass-data processing, probabilistic characteristics are built in the form of histograms of the density distribution of average power and regenerative energy amount within three suggested approaches. Major technical parameters of on-board capacitive storage, i. e. nominal and maximal power, operational and total energy capacity are determined with the aid of the above-mentioned approaches for specified operational conditions of the metro train. Originality. For the first time approaches for determination of parameters of on-board capacitive energy storage for metro train according to the analysis of distribution density of average power and amount of regenerated electricity are proposed. Research on determination of parameters of on-board capacitive energy storage for metro rolling stock with brake regenerative systems got further development. Practical value. The suggested approaches can be used for construction of metro rolling stock with on-board capacitive energy storage.

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In the article a comparative analysis of existing methodologies and approaches on the parameters determination of the capacitive energy storages for a metro train with energy recovery systems was performed, disadvantages of each of them were determined. A complex approach for estimation of the on-board capacitive energy storage parameters was proposed; the point of approach consists in determination of the rational power and energy capacity for two parameters of the storage system at once – mass and payback period. The complex approach is based on theoretical researches, which require simulation of the metro train equipped with recuperation system operation by mean of developed software. The objective function was represented and boundary values for the power and energy capacity during determination of the rational parameters of the on-board capacitive energy storage using a complex approach were specified. The recuperation system with rational parameters of the on-board capacitive energy storage for specified service conditions in Public Utility Company “Kyiv Metropolitan” and chosen research metro train was specified. Amount of energy stored due to the installation of the energy storage system with rational parameters was estimated.

Purpose. The purpose of the work is to determine the rational capacity and energy consumption of the onboard capacitive energy storages using a complex approach for estimating the parameters, which is based on the methods of theoretical research. Methodology. The article performs a comparative analysis of existing methodologies and approaches for determination of the onboard capacitive storages parameters for subway trains with recovery systems, formulates the advantages and disadvantages of each of them. It is determined that among the existing methodologies it is most reasonable to use a complex approach, the aim of which is to determine the rational capacity and energy consumption according to two parameters of the energy storage system – weight and payback period. A procedure for determining the rational parameters of the onboard capacitive energy storage using theoretical research methods is proposed: theoretical basis of electric traction, mathematical modeling of dynamic motion and energy processes, mathematical statistics, technical-economic and comparative analysis. Findings. According to the results of the complex theoretical researches, the economic expediency of implementation of onboard capacitive energy storages on the subway train is confirmed. The energy storage system with rational parameters of the onboard capacitive energy storage for established operating conditions in the Municipal Enterprise «Kyiv Metro» and selected experimental train of the subway is determined. The amount of saved electricity due to the implementation of the energy storage system with rational parameters is estimated. Originality. The methodology for determining the rational parameters of the onboard capacitive energy storage in terms of replacing the use of experimental research data with theoretical research, the purpose of which is to model the movement of subway trains with recovery systems using software to reduce financial costs, research time and increase their accuracy. The research on determination of quantitative indicators of recovery electricity for the analysis of energy saving reserves was further developed in the subway. Practical value. The results of theoretical research can be the basis for the creation of full-scale samples of subway trains with onboard capacitive energy storages. The researches will create recommendations for the design of innovative energy-saving subway trains with improved technical and economic characteristics that can increase the efficiency of the transportation process in the subway.

Purpose. Justification of the need for electrical energy quality technical accounting based on the results of monitoring a 10 kV traction substation transformer mode. Methodology. Measurements of the current and voltage at secondary busbars of a 10 kV traction substation and monitoring of the electrical energy parameters in the observation interval were carried out. Using the Fourier analysis methods, a current and voltage harmonics level was analyzed. For the current and voltage fundamental harmonic, the positive, negative and zero sequences components are analyzed using the Fortescue transformation. Based on the secondary voltage side current discrete spectrum, the calculation of power loss growth in cable line and transformer windings was carried out. Findings. As a result of measuring the electrical mode parameters on the transformer secondary voltage busbars, a significant distortion of current and voltage, as well as significant fluctuations in active and reactive power, were established. During the observation interval, significant changes in the power factor are noted. Based on the calculation of additional losses from current higher harmonics in the cable line, it has been established that the current load of the line can be reduced by 10% while eliminating the current higher harmonics. A similar calculation of loss growth carried out for the traction transformer showed that in the analyzed case its load should not exceed 87.8% of the nominal one. Originality. A significant level of harmonic current distortion on secondary voltage busbars of the traction transformer leads to its underutilization, whereas the voltage distortion level, as an electrical energy quality indicator in accordance with current standards, remains within the permissible range. This requires a revision of electrical energy quality indicators, from the standpoint of power, which is due to both current and voltage. Practical value. The indicators obtained as a result of calculations can be used to correct the load of traction substation transformers. The introduction of the obtained indicators into the set of parameters for electrical energy technical metering is a prerequisite for the development of measures to improve the electrical energy quality.