# 2024 № 5 Електротехніка і Електромеханіка

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/80545

## Переглянути

11 результатів

## Результати пошуку

Документ Increasing the damping properties of the magnetorheological actuator of the vehicle suspension control system(Національний технічний університет "Харківський політехнічний інститут", 2024) Dushchenko, V. V.; Liubarskyi, B. G.; Masliev, A. O.; Nanivskyi, R. A.; Masliev, V. G.; Ahapov, O. M.; Iakunin, D. I.In accordance with one of the ways of solving the problem of increasing the smoothness of the vehicles, a controlled suspension is proposed, which is created on the basis of the use of «smart» materials – magnetorheological elastomers, the mechanical properties of which, in particular, damping, can be changed with the help of a controlling magnetic field. This is implemented with the help of the magnetorheological actuator of the suspension control system, which has the form of an elastic bushing of the suspension arm, consisting of several electrically connected in series toroid-like coils (with a core of magnetorheological elastomer). The device is powered by current, the value of which is controlled by the operator, or automatically, depending on the road profile and driving mode. Magnetorheological actuators (elastic bushings) are placed in the holes of the suspension levers instead of standard rubber ones and combined with a controlled current source. Thus, the suspension becomes controllable, which makes it possible to set the necessary vibration damping of the vehicle body to increase its smoothness. Problem. The disadvantage of the previous designs of the magnetorheological actuator is the insufficient amount of the magnetic flux density and the unevenness of its distribution within the elastic bushings. As a result, the damping properties of such controlled suspensions become insufficiently effective, which reduces the possibility of increasing the smoothness of the vehicles. The purpose of the work is to increase the damping properties of the magnetorheological actuator of the vehicle suspension control system, which will increase the control efficiency. The task is to improve the design of the performing magnetorheological device, to carry out calculations and develop a calculation scheme of the study, to determine the average magnetic flux density value and its distribution across the cross-section of the device, to calculate the dependence of the device damping indicator on the magnetic flux density, to compare the damping indicators of the improved device with previously known ones. Methodology. Research tasks were solved on the basis of magnetic field analysis using methods of magnetic field theory and SOLIDWORKS® and FEMM software packages, as well as analysis of the dependence of the damping properties of bushings from magnetorheological elastomers on magnetic flux density. A description of the design and principle of operation of the magnetorheological actuator of the vehicle suspension characteristics control system is given, based on which the calculation scheme was developed. Results. The results of research calculations showed that the average value of magnetic flux density in the proposed design of the device reached 0.85 T, its distribution became fairly uniform, and there were no zones where it was abnormally small. For the first time, the dependence of the damping index on the magnetic flux density of the controlling magnetic field has signs of scientific novelty. It was found that this indicator for the proposed design of the device increased by 22 % compared to previous other designs, which will increase the efficiency of the control system and the smoothness of the vehicle. A positive result was achieved due to the following features of the proposed design of the suspension actuator: the elastic sleeve consists of several coaxially located actuators made of anisotropic magnetorheological elastomer, in which the conglomerates of the ferromagnetic filler during the manufacturing process are located collinear to the direction of the angular deformations of the sleeve and the control magnetic field flux density vector, and the devices have control coils located on their surfaces, which are made of conductive elastic elastomer and electrically connected in a series circuit. Originality. The control method, previous designs and construction of this controlled suspension are protected by patents of Ukraine. Practical value. The direction of further research is to optimize the parameters of the control coils in order to reduce the energy consumption for them and to protect them from overheating.Документ Power fluctuation suppression for grid connected permanent magnet synchronous generator type wind power generation system(Національний технічний університет "Харківський політехнічний інститут", 2024) Nid, A.; Sayah, S.; Zebar, A.Weather changes lead to create oscillations in values of power extracted from renewable energy resources (RERs). These power oscillations pose significant challenges in RERs integration process with the power grid systems, through its effects on power system stability. Many studies have been performed in various methods to mitigate the output power fluctuation of wind power generation system (WPGS). Purpose. This study focuses on increasing the mitigation rate of the output power fluctuation of WPGS caused by the rapid wind speed changes during wind gusts. Superconducting magnetic energy storage (SMES) system through its properties represents an effective solution for the WPGS power fluctuation issue. WPGS and SMES systems are linked to power grid system through the point of common coupling (PCC). Methods. This paper proposes two robust controllers for controlling the SMES system. The first controller is a Fuzzy Logic Controller (FLC), which has been utilized for controlling the power exchange between the SMES coil and the PCC of the utility grid. While the second controller is a PI controller, which have been utilized to regulate the voltages between the two sides of the PCC and the DC link capacitor in the SMES system. The proposed controllers have been constructed so that can make the SMES system absorb/deliver the real power instantaneously from/toward PCC according the wind speed changes. MATLAB/Simulink has been utilized to simulate the system under study and test the performance of proposed controllers. In addition, two different wind speed scenarios have been used in the simulation. Practical value. Results of simulation have proven the effectiveness of proposed controllers so that the active power fluctuation delivered to utility grid can be reduced by up to 89 %.Документ Analytical solution of conductor tensile force in asymmetrical spans used in overhead power lines and substations with influence of tension insulators(Національний технічний університет "Харківський політехнічний інститут", 2024) Bendik, J.; Cenky, M.; Paulech, J.; Goga, V.Designing electrical substations involves analyzing the horizontal tensile force in flexible tension conductors under varying temperatures. These temperature changes affect the conductor’s length and forces. Problem. Existing methods for calculating horizontal tensile force in conductors often focus on symmetric spans or require complex finite element modeling (FEM), which is impractical for routine substation design. Asymmetric spans with tension insulators present a more complex challenge that current solutions do not adequately address. Purpose. Universal analytical solution and algorithm for calculating the horizontal tensile forces in conductors in asymmetric spans with tension insulators used in power substations or short overhead power line spans. The solution is designed to be easily implementable in software without requiring complex tools or extensive FEM. Methodology. The methodology involves deriving an analytical solution based on the catenary curve formed by the conductor between attachment points at different heights. The analysis includes calculating the conductor’s length for a given tensile force and using a state change equation to determine forces under new temperature conditions. Validation is performed using FEM calculations. Results. The proposed solution was validated against FEM models with varying height differences (5 m and 15 m) and conductor temperatures (–30 °C, –5 °C, +80 °C). The results showed a minimal error (less than 0.15 %) between the analytical solution and FEM results, demonstrating high accuracy. Originality. This paper presents a novel analytical solution to the problem of calculating tensile forces in asymmetric spans with tension insulators. Unlike existing methods, our solution is straightforward and easily implementable in any programming language. Practical value. The solution is practical for routine design tasks in electrical substations or short overhead power lines. Especially in power substations, accurate tensile forces are needed not only for mechanical design and sag calculations but also for calculating the dynamic effects of short-circuit currents.Документ Features of distribution of electric field strength and current density in the reactor during treatment of liquid media with high-voltage pulse discharges(Національний технічний університет "Харківський політехнічний інститут", 2024) Boiko, M. I.; Makogon, A. V.Development and use of a mathematical model of the stages of formation of high-voltage pulse discharges in gas bubbles in the discharge gap «rod-plane» to identify the features of the electric field intensity distribution in the reactor and determine the current density in the load during disinfection and purification of liquid media by high-voltage pulse discharges and find the most rational treatment. Methodology. To achieve this goal, we used computer modeling using the finite element method as a method of numerical analysis. An experimental reactor model was created that takes into account the dynamics of discharges in gas bubbles in water. The equations describing the system include the generalized Ampere equation, the Poisson equation and the electric displacement equation, taking into account the corresponding initial and boundary conditions, as well as the properties of materials. The dependence of the potential of a high-voltage electrode on time has the form of a damped sinusoid, and the specific electrical conductivity in a gas bubble is a function of time. Processes occurring at the front of the voltage pulse from 0 to 20 ns are considered. Results. It is shown that with an increase in conductivity and high-voltage potential to amplitude values in a gas bubble, the electric field strength in the water layer in the reactor reaches 70 kV/cm, and it is in the water layer that there is a strong electric field. The calculations show that already by 19th ns the density of conduction currents in water prevails over that of displacement currents. At the same time, additional inclusions in the water significantly affect the distribution of electric field strength and current density, creating a significant difference in their values at the boundaries of the interface between the bubble, conductive element and water. Originality. A simulation of the dynamics of transient discharge processes in a gas bubble and a layer of water with impurities was carried out, including an analysis of the distribution of the electric field strength and current density in a system with rod-plane electrodes in the phase transition section of a gas bubble-water. This approach allows us to reveal the features of processes in reactors and to investigate the influence of phase transitions on the distribution of electrophysical quantities. Practical value. Computer simulations confirm the prospect of using nanosecond discharges generated in gas bubbles within a volume of water for widespread industrial use and are of great interest for further experimental and theoretical research.Документ Magnetic field of electrical heating cable systems of the floors for residential premises(Національний технічний університет "Харківський політехнічний інститут", 2024) Rozov, V. Yu.; Reutskiy, S. Yu.; Pelevin, D. Ye.; Kundius, K. D.In order to effectively protect public health from the magnetic field of electric heating cable systems of the floors, it is necessary to reduce it to a safe level. However, this requires careful study of the magnetic field. The purpose of the work is to develop a mathematical model and a verified methodology for calculating the magnetic field of electric heating cable systems of the floors in residential premises, and assessment of compliance of the magnetic field with the normative level. Method. A methodology for calculating the magnetic field of electric heating cable systems of the floors in residential premises has been developed. Scientific novelty. Based on Bio-Savar’s law and the principle of superposition, an analytical model of the magnetic field of electric heating cable systems of the floors and its calculation method was created. The magnetic field of the coaxial heating cable is determined, taking into account the value of its maximum eccentricity. The experimentally substantiated correctness of the obtained theoretical statements, which is confirmed by their coincidence with the results of the experiment with a spread of less than 7 %. Practical significance. A verified methodology for calculating the magnetic field of electric heating cable systems of the floors was proposed and an assessment of compliance of their magnetic flux density with the normative level of 0.5 μT was performed. It is recommended to lay modern two-wire heating cables at a depth of at least 75–100 mm from the floor. With a smaller laying depth, it is recommended to use coaxial heating cables, which have an order of magnitude smaller magnetic field.Документ Enhancing off-grid wind energy systems with controlled inverter integration for improved power quality(Національний технічний університет "Харківський політехнічний інститут", 2024) Muthukaruppasamy, S.; Dharmaprakash, R.; Sendilkumar, S.; Parimalasundar, E.Off-grid wind energy systems play a pivotal role in providing clean and sustainable power to remote areas. However, the intermittent nature of wind and the absence of grid connectivity pose significant challenges to maintaining consistent power quality. The wind energy conversion system plays a central role in tapping renewable energy from wind sources. Operational parameters such as rotor and stator currents, output voltages of rectifiers and converters, and grid phase voltage variations are crucial for stable power generation and grid integration. Additionally, optimizing power conversion output through voltage gain analysis in boost converters is essential. Moreover, ensuring electricity quality via total harmonic distortion reduction in inverters is vital for grid compatibility. Goal. Enhancing the power quality of grid-integrated wind energy conversion systems. Methods. The proposed topology is implemented in MATLAB/Simulink with optimized control strategies for enhancing power quality in off-grid wind energy systems. Results. Control strategies with a grid -connected wind energy conversion system yields substantial improvements in power quality. This includes effectively mitigating voltage fluctuations and harmonics, resulting in smoother operation and reduced disturbances on the grid. Practical value. The proposed topology has proven to be extremely useful for off grid-integrated wind system.Документ Wild horse optimization algorithm implementation in 7-level packed U-cell multilevel inverter to mitigate total harmonic distortion(Національний технічний університет "Харківський політехнічний інститут", 2024) Ebrahimi, F.; Windarko, N. A.; Gunawan, A. I.Multilevel inverters (MLIs) are a popular industrial and, more especially, renewable energy application solution. This is because of its appetite for filters, low distortion class, and capacity to provide a multilayer output voltage that resembles a pure sine waveform. The novelty is in applying the wild horse optimization algorithm (WHOA) to adjust the sinusoidal pulse width modulation (SPWM) technique by producing the optimal reference signal parameters in a new multilevel inverter architecture known as the packed U-cell multilevel inverter (PUC-MLI). Purpose. This study helps with the idea of new inverter architecture and a modified pulse width modulation (MPWM) method to make the multilevel inverter smaller, cheaper, and with less total harmonic distortion (THD). Methods. We use the proposed approach to control a 7-level, single-phase PUC-MLI. The WHOA is used to discover the optimal parameters of the additional reference sine signal after being compared with SPWM to evaluate its performance in harmonic reduction. The simulation’s outcome was validated by building a PUC-MLI prototype. Results. Experimental results and simulations validate the effectiveness of the suggested approach. The WHOA-improved MPWM approach achieves a significant reduction in THD on the PUC-MLI output voltage, as indicated by the results. Practical value. THD in MLI output voltage will be reduced without spending any cost. The suggested solution works with many MLI topologies with varying output voltage levels.Документ Dspace implementation of real-time selective harmonics elimination technique using modified carrier on three phase inverter(Національний технічний університет "Харківський політехнічний інститут", 2024) Djafer, L.; Taleb, R.; Mehedi, F.In the contemporary world, alternative electrical energy has become an integral part of our daily existence, with the majority of our electrical materials, electronic devices, and industrial equipment relying on this energy source. Consequently, ensuring the quality of the electrical signal obtained is of paramount importance in the process of converting and distributing electrical energy. The improvement of the output voltage inverter can be achieved through adjustments to the inverter structure or by refining the control strategy. The novelty of the presented research lies in an innovative approach that employs real-time modulation for efficient control over the reduction of harmonics, alongside managing the fundamental component. This approach is applicable to both bipolar and unipolar configurations, featuring quarter-wave and half-wave symmetries. Purpose. Employing this modulation strategy aims to enhance the durability of the switching components and enhance the voltage output of the inverter. Methods. The methodology is founded on a sine-sine modulation as its foundational model. It constitutes an inventive pulse width modulation technique in which a reference sinusoidal waveform, operating at the desired signal frequency, is compared to a modified carrier signal with an identical time period as the reference signal. Results. This paper introduces a broader and more comprehensive approach, alongside specific solutions, for the control and mitigation of harmonics in three phase voltage source inverters. The proposed method offers precise control over the reduction of harmonics and the fundamental component, and it can be implemented in extensive power electronic converters. Practical value. To assess the effectiveness of the given control approach, we conducted simulations as well as real-time implementation employing Dspace DS1104 controller board. The outcomes were highly favorable, confirming the effectiveness and validity of the suggested control algorithm.Документ Experimental validation of fuzzy logic controller based on voltage perturbation algorithm in battery storage photovoltaic system(Національний технічний університет "Харківський політехнічний інститут", 2024) Bounechba, H.; Boussaid, A.; Bouzid, A.Solar photovoltaic (PV) has recently become very important especially in electrical power applications for countries with high luminosity because it is an effectively unlimited available energy resource. Depending on solar radiation and temperature, the PV generator has a non-linear characteristic with a maximum power point (MPP). The novelty is the efficiency improvement of a PV energy module, it is necessary to track the MPP of the PV array regardless of temperature or irradiation circumstances. Purpose. This paper presents the modeling and the digitally simulation under MATLAB/Simulink of a Fuzzy Logic Controller based on Voltage Perturbation Algorithm (FLC-VPA) applied to PV battery charging system, which consists of PV module, DC-DC boost converter, MPP tracking (MPPT) unit and battery storage. Methods. The DSP1104 is then used to experimentally implement this MPPT algorithm for real-time driving. The obtained results show the high precision of the proposed FLC-VPA MPPT around the optimal point compared to the conventional VPA under stable and changing meteorological conditions. Practical value. The experimental results approve the effectiveness and validity of the proposed total control system in the PV system.Документ Fractional-based iterative learning-optimal model predictive control of speed induction motor regulation for electric vehicles application(Національний технічний університет "Харківський політехнічний інститут", 2024) Nemouchi, B.; Rezgui, S. E.; Benalla, H.; Nebti, K.A new control strategy based on the combination of optimal model predictive control (OMPC) with fractional iterative learning control (F-ILC) for speed regulation of an induction motor (IM) for electric vehicles (EVs) application is presented. OMPC uses predictive models to optimize speed control actions by considering the dynamic behavior of the IM, when integrated with the F-ILC, the system learns and refines the speed control iteratively based on previous iterations, adapting to the specific characteristics of the IM and improving performance over time. The synergy between OMPC and F-ILC named F-ILC OMPC enhances the precision and adaptability of speed control for IMs in EVs application, and optimizes the energy efficiency and responsiveness under varying driving conditions. The novelty lies in the conjunction of the OMPC with the ILC-based on the fractional calculus to regulate the speed of IMs, which is original. Purpose. The new control strategy provides increased performance, robustness and adaptability to changing operational conditions. Methods. The mathematical development of a control law that mitigates the disturbance and achieves accurate and efficient speed regulation. The effectiveness of the suggested control strategy was assessed via simulations in MATLAB conducted on an IM system. Results. The results clearly show the benefits of the F-ILC OMPC methodology in attaining accurate speed control, minimizing steady-state error and enhanced disturbance rejection. Practical value. The main perspective lies in the development of a speed control strategy for IMs for EVs and the establishment of reliable and efficient electrical systems using ILC-OMPC control. This research has the prospect of a subsequent implementation of these results in experimental prototypes.