Tekhnichna Elektrodynamika

Journal Information
ISSN / EISSN : 1607-7970 / 2218-1903
Total articles ≅ 507
Current Coverage

Latest articles in this journal

O.G. Shpolianskyi
Tekhnichna Elektrodynamika, Volume 2021, pp 51-57; https://doi.org/10.15407/techned2021.06.051

The paper analyses the transient currents during the energisation of a 750 kV overhead transmission line (OTL). The safety of OTL state after symmetrical and asymmetrical closing of the circuit breakers and technical feasibility of SF6 circuit breakers opening with time delay after their closing is substantiated. The necessity of transient processes simulation for analysing the characteristics of periodic and direct components of currents is shown. A method for determining of SF6 circuit breaker opening time delay for a set of the states that may arise after the energisation of OTL is developed. References 13, tables 2, figures 5.
Yu.M. Vasetsky, Institute of Electrodynamics National Academy of Sciences of Ukraine, I.P. Kondratenko
Tekhnichna Elektrodynamika, Volume 2021, pp 3-12; https://doi.org/10.15407/techned2021.06.003

On the basis of the developed analytical mathematical model of non-stationary process of local electrodynamic treatment of metal structures, especially welded joints, and estimation of the main dynamic, electrophysical and thermal characteristics of the process are considered. The characteristics of the motion of the electrode, the distribution of the pulse current in the metal plate, the heating of the metal are found and analyzed. The conclusion about the possibility of realization of devices with simultaneous supply of current pulses of necessary parameters on the shock electromagnetic element and through an electrode to the metal plate to achieve the effect of electroplasticity is made. References 19, figures 9, tables 2.
V. Pankiv, Ye. Tankevych, , Khokhlovych Family Street Dtek Grids Llc
Tekhnichna Elektrodynamika, Volume 2021, pp 58-67; https://doi.org/10.15407/techned2021.06.058

The classification is carried out and the characteristics, capabilities and disadvantages of the known methods of programmed correction of the output current of a single-phase primary measuring channel (PMC) of the current are determined. A discretized model of short-circuit current (SCC) is proposed. A method and an algorithm for increasing the accuracy of a three-phase current PMC in transient modes of electric power systems (EPS) under the condition of saturation of the magnetic circuits of its phase current transformers have been developed. The reliability of the developed method is confirmed by simulation of the PMC output current under the condition of phase-to-phase short-circuit of phases A and B without correction and with correction of its phase currents. It is shown that the developed method makes it possible to reduce the total error of the PMC in the transient modes of the EES under the condition of saturation of the magnetic circuits of the CT from 70-90% to 6-15%. References 47, figures 6, table 1.
G.V. Bezprozvannych, National Technical University ", I.O. Kostukov, E.S. Moskvitin, Kharkiv Polytechnic Institute"
Tekhnichna Elektrodynamika, Volume 2021, pp 13-19; https://doi.org/10.15407/techned2021.06.013

Based on the proposed model of spatially inhomogeneous two-layer insulation in the form of a series-parallel substitution scheme with three relaxation chains, the calculated recovery voltage curves of phase and belt paper-impregnated insulation of power cables are obtained. The model was verified by comparison with the experimental voltage curve of the power cable with paper-impregnated insulation at a voltage of 6 kV. The possibility of separation of delayed absorption processes in inhomogeneous insulation is substantiated on the basis of the analysis of high-frequency components of the spectrum of time dependences of the recovery voltage curves. The effectiveness of wavelet transform for detailing the absorption characteristics of inhomogeneous insulation of power cables is confirmed. The presence of two maxima and the dynamics of change of the ratio between them in the process of aging of inhomogeneous insulation on the reproducible curves of the regenerative voltage of power cables are established. Based on the relationship between the two amplitude values of the reproducible reduction voltage, the preferred absorption processes are determined and the appropriate criteria for assessing the state of inhomogeneous insulation of power cables are established. References 16, figure 5.
Ruiqing Lian, Yiran You, Yong Li, Shiwei Su, Ltd. Quanzhou Power Supply Company Of State Grid Fujian Electric Power Co.
Tekhnichna Elektrodynamika, Volume 2021, pp 41-50; https://doi.org/10.15407/techned2021.06.041

The problem of wind power abandonment in the north areas of China is serious, which is mainly caused by the uncertainty of wind power and the "thermoelectric coupling" characteristics of cogeneration units. Aiming at this problem, this paper establishes the optimal scheduling model of generation-load-storage coordination in the electrothermal joint system with the goal of minimizing the amount of wind power discarded and the total scheduling cost of the system. Firstly, the responsive electrical and thermal loads on the demand side are divided into three types according to their types, namely, translatable, transferrable and reducible, and the demand response models are constructed to improve the fineness of the optimization on the demand side. Then, the scenario method is used to solve the uncertainty problem of wind power. Meanwhile, the influence of the energy storage side on system scheduling is considered. Finally, the results based on examples verify the effectiveness of the proposed model in promoting the absorptive of wind power and improving the overall economic benefit of the system. References 23, figures 8, table 1.
O.V. Kyrylenko, , I.M. Kucheriava
Tekhnichna Elektrodynamika, Volume 2021, pp 29-40; https://doi.org/10.15407/techned2021.06.029

The review concerning application of fiber-optic technologies in power industry, in particular, for monitoring of modern power cables with cross-linked polyethylene insulation and integrated fiber-optic module is carried out. The new intelligent tools for control of electrical, thermal and mechanical characteristics and partial discharges in power cable lines are presented. The current operational experience for the system of Smart Cable Guard in an emergency is described. The prospects to develop and use the intellectual technologies for monitoring of technical state of up-to-date high-voltage cable power lines and their operate reliability are grounded by analysis of new diagnostic methods controlling the level of partial discharges, temperature distribution and mechanical damage in polyethylene insulation and other elements of the high- and extra-high-voltage cables with integrated fiber-optic modules. References 51, figures 8.
Yu.O. Denysov, O.O. Bursala
Tekhnichna Elektrodynamika, Volume 2021, pp 20-28; https://doi.org/10.15407/techned2021.06.020

A comparison of the parameters of the transient characteristics of the module-optimized closed-loop transfer current of the positioning system without taking into account and taking into account the deep pulse-width modulation of the supply voltage of the linear motor. Their essential difference on speed, overregulation, static error is established. A method of optimization according to the criterion of current circuit speed is proposed, which allows to realize its transient characteristic during a finite number of switching intervals of the pulse-width converter. The synthesis of a digital current loop controller is performed, it allows to realize its transient characteristic without over-regulation during a finite number of switching intervals. The results obtained are based on the transfer function of a pulse-width converter, which is a link in the current loop. It is obtained for the case of deep pulse-width modulation based on the statistical linearization of piecewise-linear modulation characteristics of the channels of the pulse-width converter model. The modulation characteristics are obtained as a result of the expansion of the latitude-modular voltage for multiple values of the control coordinate in the Walsh-Fourier series. The number of Walsh functions taken into account depends on the approximation error and the cutoff frequency of the system. References 11, figures 3.
, P.I. Borshchov, , , O.D. Vasylenko
Tekhnichna Elektrodynamika, Volume 2021, pp 68-77; https://doi.org/10.15407/techned2021.06.068

The differential method of conductometric measurements does not fully solve the problem of the influence of changes in the background electrical conductivity of the working buffer solutions on the results of conversion of the biosensor responses. The variation in the background electrical conductivity of the buffer solution upon addition of the highly conductive analyte acts as a common mode interference and causes the additive error. Here we present a new measurement method and structure of the device for quantification of the analytes that provide a significant decrease in the measurement error associated with a change in the background electrical conductivity caused by the introduction of the analyte to the working solution prior to the generation of the informative signal. A block diagram of the device and a vector model of the balancing process of its measuring circuit are presented. The advantages of the developed method and biosensor analyzer for application within the possible changes of the transducer parameters and measurement conditions are demonstrated. References 28, figures 4.
O.L. Karasinskiy, Yu.F. Tesik, R.M. Moroz
Tekhnichna Elektrodynamika, Volume 2021, pp 78-83; https://doi.org/10.15407/techned2021.06.078

The principles of functioning of the specialized multiphase Electrical Power Standard (EPS) combined with the measuring instrument (MI) of parameters of signals of electric networks controlled by the general microcontroller are offered and analyzed. Methods and algorithms of correction of parameters of output signals of EPS by taking into account results of measurement of the specified parameters in MI are developed and investigated. An equivalent correction scheme of n-th harmonic is proposed. References 20, figures 5.
R.S. Kryshchuk, S.I. Gavryluk, A.A. Tsugankova
Tekhnichna Elektrodynamika, Volume 2021, pp 38-48; https://doi.org/10.15407/techned2021.05.038

The development of a reliable gearless electric drive for antennas of ship radars is an important problem. To solve the problem, this article proposes to use an axial induction motor (AIM) with a massive bimetallic disk-shaped rotor. The AIM model is presented, which consists of three computational domains with the boundary condition of symmetry. To calculate the electromagnetic field, a well-known analytical method of integral transformations is used taking into account the variable along the radial coordinate of the linear speed of the rotor. Ready-to-use expressions are presented for the development of a program for the numerical calculation of the magnetic field and energy characteristics of the motor. Algorithm is developed for calculating the dimensions of the AIM, operating at different speeds with a frequency converter. The numerical calculation program is used to calculate the dimensions AIM. It uses well-known recommendations for the parameters of the electromagnetic field in the magnetic core and in the air gap. The calculation of the dimensions of the AIM for ship radars “Mius” is performed. The dependence of the efficiency on the current frequency for different rotor’s frequencies is investigated. The energy indicators of the AIM are investigated at a variable torque on the shaft and at different rotor speeds. The parameters of the power source for the AIM of ship radars are established. References 20, figures 5, tables 3.
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