2024 № 3 Електротехніка і Електромеханіка

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/76883

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Solar shunt active power filter based on optimized direct power control strategy with disturbance rejection principle
(Національний технічний університет "Харківський політехнічний інститут", 2024) Boudechiche, Ghania; Aissa, Oualid; Sarra, Mustapha; Griche, Issam
Introduction. This paper focuses on a renewable energy system coupled to a dual purpose power grid via a parallel active power filter for injecting photovoltaic energy into the grid and improving the power quality in the presence of the non-linear load. The novelty of the work consists in the combination of two advanced techniques – Fuzzy Logic Controller (FLC) and the optimized Anti-Windup Fractional Order Proportional-Integral Differentiator (AW-FOPID) regulator based on Particle Swarm Optimization with the Spreading Factor (PSO-SF) algorithm, applied to the improved Direct Power Control (DPC) strategy under different conditions related to climate changes and healthy or infected electrical network. Purpose. Its main role is to improve the power quality and reject the perturbations deforming the electrical network under distorted, unbalanced and balanced grid voltage conditions. Besides, the FLC is employed the Maximum Power Point Tracking (MPPT) under any weather conditions. In addition, the optimized AW-FOPID controller leads to keep the DC bus voltage at its reference value with small undershoots and overshoots in the voltage with a short response time in steady or dynamic states. Methods. The rejection of disturbances affecting the grid is offered by the improved DPC. On the other hand, an intelligent method based on fuzzy logic was used MPPT under any weather conditions. Furthermore, an AW-FOPID regulator based on PSO-SF algorithm is used to keep the DC bus voltage at its reference value with small undershoots and overshoots in the voltage, while keeping a fast response time. Results. The proposed system control is evaluated in various states of power source: distorted, unbalanced, and balanced by simulation using MATLAB/Simulink. The simulation results illustrate the effectiveness and performance of the studied control strategies.
The effect of thermal ageing on electrical and mechanical properties of thermoplastic nanocomposite insulation of power high-voltage cables
(Національний технічний університет "Харківський політехнічний інститут", 2024) El Sherkawy, Eman; Nasrat, Loai S.; Rihan, Mahmoud
This research explores the thermal ageing influence on the Low Density Polyethylene (LDPE) dielectric properties, which is utilised as electrical insulation in high-voltage cables. An accelerated thermal ageing test was done at four temperature ranges ranging from 25 °C to 120 °C to define the degree of material deterioration under thermal ageing and to prevent its failure. LDPE composite samples were made by adding aluminium oxide (Al2O3) inorganic filler in two different grain sizes (nano and micro) with various concentrations. The effect of adding inorganic filler on the acceleration of the thermal ageing of the polymer was studied by heating the samples for different periods of time and measuring the dielectric strength of the samples. The obtained results show that thermal ageing considerably affects the electrical properties of the material. The LDPE/Al2O3 nanofiller sample has the highest dielectric strength value at different temperatures. Thermogravimetric analysis was used to investigate the thermal characteristics of materials. The mechanical characteristics of LDPE polymer are studied using tensile strength and elongation at break tests.
Electrical engineering equipment for generating and measuring of complete pulse current of artificial lightning in the conditions of high-voltage electrophysics laboratory
(Національний технічний університет "Харківський політехнічний інститут", 2024) Baranov, M. I. ; Buriakovskyi, S. G.
Goal. Decision of problem scientific and technical task on the reliable generating and measuring in the conditions of high-voltage electrophysics laboratory basic component of complete pulse current of artificial lightning with the rationed amplitude-temporal parameters (ATPs) with the use of the modernized generator of current of lightning of type of UITOM-1. Methodology. Bases of the applied electrical engineering, electrodynamics and electrophysics, electrophysics bases of technique of high-voltage and high pulse currents, bases of high-voltage pulse technique and measuring technique. Results. Information, which specify on a decision at Research and Design Institute "Molniya" of National Technical University "Kharkiv Polytechnic Institute" problem scientific and technical task, related to the reliable generating and measuring in the conditions of high-voltage electrophysics laboratory of complete pulse current of artificial lightning, which contains pulse A- (repeated pulse D-), intermediate B- and long-term C- (shortened long C*-) components of this current, is resulted, ATPs which answer the hard technical requirements of normative documents of the USA of SAE ARP 5412: 2013, SAE ARP 5414: 2013 and SAE ARP 5416: 2013. Short information is indicated about the applied electrical circuits of separate high-voltage generators of pulse currents of condenser type of GIC-A (GIC-D), GICB and GIC-C (GIC-C*), which it is worked as synchronous appearance on the general electrical loading in composition the modernized powerful high voltage generator of complete pulse e current of artificial lightning of type of UITOM-1, and in-use highvoltage measuring facilities which contain the heavy-current low-resistance shunts of type of SHK-300 for simultaneous registration with their help on examinee on stability to lightning devices objects of aviation and space-rocket technique of ATPs proper component of complete i pulse current of artificial lightning. Technical examples are resulted and the row of results of practical application of the indicated domestic powerful high-voltage proof-of-concept electrophysics equipment is described at the tests of elements of some aircrafts (ACs) on resistibility to the direct action on them of complete pulse current of artificial lightning with rationed ATPs. Originality. A problem is formulated and having the important applied value in area of aviation and space-rocket technique for the leading countries of the world scientific and technical task on the reliable generating and measuring in the conditions of high-voltage electrophysics laboratory indicated component of complete pulse current of artificial lightning with rationed ATPs and concrete electro-technological ways and hardware are indicated for its successful decision. Practical value. The use of the modernized powerful high-voltage generator of complete pulse current of artificial lightning of type of UITOM-1 developed in practice and created in Ukraine will allow to conduct the real verification on resistibility to the action of lightning of different side systems, devices and construction elements, containing metallic and composition materials, both again developed and modernized ACs, that will be instrumental in the increase of vitality of such ACs in the extreme terms of their flight and stay in an electrical active earthly atmosphere with flowing in it storm electrical discharges.
Analytical determination of a quasi-stationary electromagnetic field created by magnetic moments and eddy currents in conducting half-space
(Національний технічний університет "Харківський політехнічний інститут", 2024) Vasetsky, Yu. M.
Aim. Study of the distribution of a three-dimensional alternating quasi-stationary electromagnetic field at the surface of conducting half-space with strong skin-effect, the source of which is an arbitrarily oriented magnetic moment. Methodology. The expressions for non-uniform electromagnetic field with strong skin effect are used for the analysis, which is based on the found exact analytical solution of the general three-dimensional problem and the use of expansion into asymptotic series with respect to a small parameter that is proportional to the ratio of the field penetration depth to the distance between the sources of the external field and the surface of body. Specific expressions at the surface are completely determined by the known field of external sources. In this work, the external magnetic moment field is used. Results. For strong skin effect, expressions for the electric and magnetic field strength are obtained separately for the components of the magnetic moment oriented perpendicularly and parallel to the flat surface between the dielectric and conducting areas. The features of the electromagnetic field distribution are analyzed depending on the value of introduced small parameter. The results are presented for the module and phase shift of the field strength with respect to the phase of the external field source. Originality. The expressions found for the electromagnetic field appear to be more general than the use of closed contours with alternating current, since they extend types of external field sources and allow the use of the superposition method instead of integration over the entire contour. Practical value. The found specific analytical expressions of the electromagnetic field at the surface for the external field of magnetic moments significantly simplify the solution of the problems, since they do not require additional solution of the field equations.
Obtaining the maximum power from the source using step-up and step-down type pulse regulators that work on battery
(Національний технічний університет "Харківський політехнічний інститут", 2024) Romashko, V. Y.; Batrak, L. M.; Abakumova, O. O.
Introduction. Pulse regulators are widely used to match the output resistance of the source with the load resistance in order to ensure the possibility of taking maximum power when the value of the load resistance changes. Problem. In the case of using nontraditional and renewable sources of electrical energy, for a more uniform supply of energy to the load, a battery is often connected to the output of the pulse regulator, which works in buffer mode. In such cases, the load for the pulse regulator will be the battery itself, and the role of the source load will be performed by the input resistance of the regulator. To ensure the mode of operation of the pulse regulator, in which the maximum power will be transmitted from the source to the load, it is necessary to know the regulating characteristics of the regulator. There are works that analyze the regulating characteristics of step-up and step-down pulse regulators, which are used to match the load with the output resistance of the source. At the same time, for the same purpose, pulse regulators of the step-up and step-down type can be used. Goal. The purpose of the work is to analyze the features of the operation of step-up and step-down type pulse regulators in the mode of maximum power transmission from the source to the battery, as well as to determine the conditions under which it is possible and appropriate to use such regulators for the specified purpose. Methodology. The regulating characteristics of step-up and step-down type pulse regulators with sequential and parallel switching on of the controlled key were determined and analyzed, taking into account the presence of a battery at their output. Results. It is shown that the transfer of energy from the source to the battery is possible only under certain modes of operation of the regulator, which depend on the type of regulator, as well as the amount of voltage on the battery. The conditions under which it is possible to draw the maximum power from the source are determined. Originality. Since the output resistance of the source and the load resistance are of the same order in the maximum power selection mode, the internal resistance of the power source was taken into account when determining the regulating characteristics of the regulators. Practical value. The obtained results made it possible to formulate practical recommendations for a justified choice of the regulator’s operating modes, depending on its type and the value of voltage on the battery.
Experimental electromagnetic compatibility of conducted electromagnetic interferences from an IGBT and a MOSFET in the power supply
(Національний технічний університет "Харківський політехнічний інститут", 2024) Lahlaci, Mohammed Elamine; Miloudi, Mohamed; Miloudi, Houcine
Introduction. Most electromagnetic compatibility studies carried out in the context of power switch research are generally valid for low frequencies. This frequency restriction appears to be too restrictive for a complete analysis of the electromagnetic interference conducted. The novelty of this work lies in the load-dependent an optimal selection of IGBTs and MOSFETs for least-disturbance power switching in the frequency range from 150 kHz to 30 MHz, based on an optimal experimental selection procedure and show the impact of load value on switch switching and noise generation. Purpose. Analysis of the fundamental possibility of selecting a switching device with a power supply based on an experimental measurement which allows to increase the reliability of the entire mechanism operation and significantly simplify the design. Methods. In this paper, the proposed study is used and compared with experimental results at low and high frequencies. Then, a comparison is made for conducted electromagnetic interference (common-mode and differential-mode) generated by IGBT and MOSFET for different loads, and the proposed methodology is verified on an experiment suitable for predicting terminal overvoltage analysis and conducted electromagnetic interference problems. Practical value. The primary method for establishing a conducted electromagnetic interference source for switching devices is based on IGBT and a MOSFET depending on the resistive load.
Artificial neural network and discrete wavelet transform for inter-turn short circuit and broken rotor bars faults diagnosis under various operating conditions
(Національний технічний університет "Харківський політехнічний інститут", 2024) Rouaibia, Reda; Djeghader, Yacine; Moussaoui, Lotfi
Introduction. This work presents a methodology for detecting inter-turn short circuit (ITSC) and broken rotor bars (BRB) fault in variable speed induction machine controlled by field oriented control. If any of these faults are not detected at an early stage, it may cause an unexpected shutdown of the industrial processes and significant financial losses. Purpose. For these reasons, it is important to develop a new diagnostic system to detect in a precautionary way the ITSC and BRB at various load condition. We propose the application of discrete wavelet transform to overcome the limitation of traditional technique for no-stationary signals. The novelty of the work consists in developing a diagnosis system that combines the advantages of both the discrete wavelet transform (DWT) and artificial neural network (ANN) to identify and diagnose defects, related to both ITSC and BRB faults. Methods. The suggested method involves analyzing the electromagnetic torque signal using DWT to calculate the stored energy at each level of decomposition. Then, this energy is applied to train neural network classifier. The accuracy of ANN based on DWT, was improved by testing different orthogonal wavelet functions on simulated signal. The selection process identified 5 pertinent wavelet energies, concluding that, Daubechies44 (db44) is the best suitable mother wavelet function for effectively detecting and classifying failures in machines. Results. We applied numerical simulations by MATLAB/Simulink software to demonstrate the validity of the suggested techniques in a closed loop induction motor drive. The obtained results prove that this method can identify and classify these types of faults under various loads of the machine.
Internal capacitive compensation of the reactive power of the screw electromechanical converter
(Національний технічний університет "Харківський політехнічний інститут", 2024) Zablodskiy, M. M.; Chuenko, R. M.; Kovalchuk, S. I.; Kruhliak, H. V.; Kovalchuk, O. I.
Introduction. A special category among induction machines with a massive rotor is occupied by the class of multifunctional electromechanical energy converters, which are integrated with the links of technological processes Problem. The exchange of reactive energy between the source and the electromechanical converter during periods of operation with a low load leads to a significant decrease in its efficiency and power factor. With the use of non-linear loads and taking into account possible resonance, it has become more difficult to improve the power factor by installing capacitor banks. Goal. Increasing the energy indicators of the electromechanical converter by spatial displacement of the main and additional stator windings and internal capacitive compensation. Methodology. Comparative analysis of connection schemes and spatial arrangement of stator windings when using internal capacitive compensation. Modeling and experimental studies of electromagnetic and electromechanical characteristics of a screw electromechanical converter. Results. The distribution of electromagnetic quantities was established and the choice of the angle of spatial displacement of the main and additional windings of the stator phases of the modified converter, which ensure an increase in the value of the electromagnetic torque and power factor, was justified. The results of experimental studies of the screw electromechanical converter are presented. Originality. For the first time, a method of internal capacitive compensation of reactive power is proposed for multifunctional electromechanical converters of technological purpose. Practical value. The use of the proposed method of spatial displacement of the main and additional stator windings and internal capacitive compensation will ensure an increase in the energy performance of the screw electromechanical converter.
The method for design of combined electromagnetic shield for overhead power lines magnetic field
(Національний технічний університет "Харківський політехнічний інститут", 2024) Kuznetsov, B. I.; Nikitina, T. B.; Bovdui, I. V.; Chunikhin, K. V.; Kolomiets, V. V.; Kobylianskyi, B. B.
Aim. Development of the method of designing a combined electromagnetic shield, consisting of active and passive parts, to improve the effectiveness of reduction of industrial frequency magnetic field created by two-circuit overhead power lines in residential buildings. Methodology. The problem of design of combined electromagnetic shield including robust system of active shielding and electromagnetic passive shield of initial magnetic field solved based on of the multi-criteria two-player antagonistic game. The game payoff vector calculated based on the finite element calculations system COMSOL Muliphysics. The game solution calculated based on the particles multiswarm optimization algorithms. During the design of combined electromagnetic shields spatial location coordinates of shielding winding, the currents and phases in the shielding winding of active shielding, geometric dimensions and thickness of the electromagnetic passive shield are calculated. Results. The results of theoretical and experimental studies of combined electromagnetic passive and active shielding of magnetic field in residential building from power transmission line with a "Barrel" type arrangement of wires presented. Originality. For the first time the method of designing a combined electromagnetic shield, consisting of active and passive parts, for more effective reduction of the magnetic field of industrial frequency created by two-circuit overhead power lines in residential buildings is developed. Practical value. Based on results of calculated and experimental study the shielding efficiency of the initial magnetic field determined that shielding factors whith only electromagnetic passive shield is more 2 units, whith only active shield is more 4 units and with combined electromagnetic passive and active shield is more 10 units. It is shown the possibility to reduce the level of magnetic field induction in residential building from power transmission line with a "Barrel" type arrangement of wires by means of a combined electromagnetic passive and active shielding with single compensating winding to 0.5 μT level safe for the population.
Efficiency of multi-armature linear pulse electromechanical power and speed converters
(Національний технічний університет "Харківський політехнічний інститут", 2024) Bolyukh, V. F.; Kocherga, O. I.
Introduction. High-speed linear pulse electromechanical converters (LPEC) provide acceleration of the executive element in a short active section to high speed with significant displacement, while power-purpose LPECs create powerful power impulses of the executive element on the object of influence with minor movements. One of the areas of improvement of LPEC is the creation of multi-armature structures. Methodology. To analyze the electromechanical characteristics and indicators of LPEC, a mathematical model was used, which takes into account the interconnected electrical, magnetic, mechanical and thermal processes that occur when connected to a pulse energy source with a capacitive energy storage. The main results of the calculations were performed in the COMSOL Multiphysics software environment and confirmed by experimental studies in laboratory conditions. Results. The features of the electromechanical processes of multi-armature LPECs are established and their indicators are determined. With the help of efficiency criteria, which take into account electrical, power, speed and magnetic indicators in a relative form with different options for their evaluation strategy, it was established that multi-armature LPECs for power purposes have increased efficiency, and for high-speed LPECs the use of multiarmature configurations is impractical. The conducted experimental studies confirm the reliability of the calculated results. Originality. It has been established that almost all multi-armature LPECs for power purposes have higher efficiency compared to a converter with one armature, and for high-speed LPECs it is advisable to use traditional LPECs with one armature. Practical value. On the basis of multi-armature LPECs, models of an electromagnetic UAV catapult, a magnetic pulse press for ceramic powder materials, an electromechanical device for dumping ice and snow deposits from a power line wire, a device for destroying information on a solid-state digital SSD drive have been developed and tested.