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Purpose. Justification of the fallacy of using the concept of “apparent power” for quadripole circuits in alternating sinusoidal current circuits on the basis of the instantaneous power balance. Methodology. The apparent power in electric power is a generalizing value of energy processes that researchers use provided that other power components are determined. Based on the analysis of known studies, some were found, in which the authors question such a role in apparent parent. The wellknown provisions of the electrical engineering theory are used with the application of mathematical methods, in particular trigonometry, the Euler transformation and the complex numbers theory to determine the instantaneous power components of sinusoidal current and voltage. Findings. The instantaneous power components of sinusoidal current and voltage are analytically determined in trigonometric and complex form. The corresponding vectors are represented graphically on complex planes of zero and doubled frequency. Accordingly, it is indicated which components of the instantaneous power correspond to the apparent power; in addition, the phase shifts of the latter on the corresponding complex planes are determined. For an elementary electrical circuit, they are defined for all elements of the circuit provided that the balance of instantaneous power (Tellejen’s theorem), active power, reactive power (Boucherot’s theorem) is observed. Originality. It has been proven that the order of determining the active power as the difference between the maximum value of the instantaneous power and apparent power determined by the effective values of voltage and current in sinusoidal current circuits cannot be accepted as general. Using the example of a sinusoidal current an elementary electrical circuit, it was found that for an element of electric energy transmission, the amplitude of power fluctuations, which in certain cases is called “apparent power” in general, can be less than the instantaneous power average value – active power. Practical value. The obtained results can be used to improve the power component compensation algorithms for series and parallel power active filters [ABSTRACT FROM AUTHOR]

Purpose. To analyze the energy saving reserves under the conditions of implementation and integration of the system in order to find rational driving modes in the general system of managing underground electrified transport. Methodology. The work presents the method for processing data arrays obtained experimentally with the help of a measuring system and theoretically with the use of the “Rational Trajectory” software. Findings. Experimental studies were carried out using a testing system created on the basis of a refurbished train with energy recovery system. Theoretical studies were carried out using the “Rational Trajectory” software, which is based on the principle of solving a multi-criteria problem by the method of the main criterion. The minimum amount of electricity consumption from the overhead contact line was chosen as the main criterion. The software was developed in the LabVIEW graphical programming environment in order to determine the rational modes of driving rolling stock and energy indicators in a given area of its operation. The amount of electricity consumed for traction and the amount of electricity generated by the train during regenerative braking were determined based on the results of experimental and theoretical studies, respectively, under typical and rational modes of driving the train for given identical operating conditions. Originality. Further research on the analysis of energy saving reserves on the rolling stock of underground electrified transport was achieved due to the introduction of a system for finding a rational driving mode. Practical value. It has been established that the implementation and incorporation of the “Rational Trajectory” software into the train control system will save up to 14.7 % of the amount of electricity consumed for traction, compared to typical modes operation on a given track section. [ABSTRACT FROM AUTHOR]

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Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)