Electrical Engineering & Electromechanics

Theory and practice of numerical-field analysis and refinement of electromagnetic and energy parameters in the designs of three-phase induction motors

V. I. Milykh — 2026-01-02

Introduction. The paper is devoted to improving the designs of three-phase induction motors (TIMs) based on the application of numerical calculations of their magnetic fields. Considering that the classical system for designing TIMs does not always provide sufficient accuracy of their design parameters, this task is relevant and therefore the developed motors require experimental refinement and additional time and money accordingly. Problem. In classic design of TIMs, magnetic calculations are performed based on magnetic circuit theory. The magnetic circuit of TIMs is divided into conditionally homogeneous sections, on which the magnetic quantities are considered to be distributed evenly, but their real distribution is much more complicated. This approach leads to error in determining the electromagnetic parameters of TIMs and, as a result, inaccuracies in energy, mechanical, thermal, etc. calculations. The goal of the paper is to further develop the existing system for designing TIMs by refining it using numerical-field calculations of electromagnetic and energy parameters. Methodology. The methodology is based on numerical-field verification and refinement of classical design of TIMs. It is strictly deterministic, despite the complexity of linear and nonlinear interrelationships of its structural, electromagnetic, and energy parameters, and therefore it is amenable to adequate algorithmization and programming using iterative calculations. The theoretical foundations of the methodology are reinforced by harmonic analysis of time functions of electromagnetic quantities and a refined determination of the differential leakage resistance of the stator winding. The tool for implementing the methodology is the FEMM program in conjunction with the created Lua scripts. Results. Numerical-field calculations of the electromagnetic and energy parameters of the test TIM developed according to the classical design were performed. This motor has been tested within the synchronous idle and rated load conditions. This demonstrated a sufficiently high efficiency of the provided theoretical and practical foundations of numerical-field calculations and revealed that the TIM project does not meet the declared power and voltage requirement. To reach their nominal values, the method for refining the magnetizing current of the stator winding and the rotor slip is provided. Scientific novelty of this paper is the system of numerical-field calculations of electromagnetic and energy parameters of TIMs, which, in conjunction with the iterative process, ensures its output to the specified nominal stator winding voltage and output power while simultaneously varying the magnetizing current and slip. Practical value. The methodology of numerical-field calculations of TIMs based on the FEMM program and the Lua script is recommended to be integrated into the automated design system for these motors. In addition to verifying and refining the parameters of the designed TIMs, the developed methodology and program can be used to obtain a set of refined operating characteristics in an automated calculation mode. References 29, tables 5, figures 9.

Influence of gamma radiation on the electrical and mechanical properties of on-board systems cables

G. V. Bezprozvannych — 2026-01-02

Introduction. Electrical and fiber-optic cables of on-board systems for transmitting monitoring, control and communication signals are increasingly used in nuclear power plants, aircraft systems and military applications. Such operating conditions are characterized by an increased level of ionizing radiation compared to the background: from 10 kGy in space applications to 1 GGy in the corium of a nuclear reactor. Problem. The resistance of polymer insulation to the action of ionizing radiation is determined on the basis of mechanical, thermophysical, physicochemical indicators that reflect the local characteristics of the polymer insulation of electrical cables. Modern special radiation-resistant optical fibers are capable of operating under the action of gamma radiation with a dose of 1 MGy. To ensure mechanical strength and protection of the optical fiber from moisture, high-strength structural elements and hydrophobic fillers are used in the optical cable. The goal of the work consists in establishing the effect of gamma radiation on unshielded cables with unshielded twisted pairs and optical cables with the determination of the dynamics of changes in the electrical properties of polyethylene insulation of conductors and mechanical properties of aramid yarns with a water-blocking coating, respectively. Methodology is based on the determination of the change in the electrical capacitance of each of the 8 polyethylene-insulated twisted pair conductors and the mechanical tensile strength of Kevlar yarns with a water-blocking compound, compared to the un-irradiated state, depending on the absorbed dose of gamma radiation of 100 kGy, 200 kGy and 300 kGy when processing samples of electrical and optical cables in the cobalt-60 (Cо⁶⁰) installation. Scientific novelty consists in establishing the criterion for achieving the critical state of polymeric polyethylene insulation of insulated conductors and the effect of the influence of a water-blocking coating with ultra-high absorption capacity on the mechanical strength of aramid yarns under the action of gamma radiation on samples of an electric cable in a protective sheath of polyvinyl chloride plastic compound and an optical cable in a protective sheath based on a polymer fire-resistant composition, respectively. Practical value is qualified by the range of radiation resistance of structural elements to ensure the operational functionality and efficiency of cables of on-board systems under the action of gamma radiation. References 50, tables 3, figures 6.

Optimal placement and sizing of distributed generation units in distribution networks using an enhanced particle swarm optimization framework

M. Al Soudi — 2026-01-02

Introduction. Optimal planning of distributed generation (DG) units is a critical research topic due to the growing integration of renewable energy and the need to enhance distribution network performance. Classical optimization methods often struggle with the nonlinear, nonconvex, and highly coupled nature of DG allocation problems. Problem. The IEEE 33-bus distribution network experiences significant voltage drops and high active and reactive power losses under normal operating conditions. Determining the optimal placement and sizing of DG units is a complex problem involving multiple interacting variables and operational constraints. Goal. This study aims to improve technical performance by minimizing total active power losses and voltage deviation while ensuring voltage stability and network reliability. Methodology. The particle swarm optimization (PSO) algorithm is enhanced using the Dehghani method (DM) – a population-based modification framework allowing all individuals, including the worst member, to contribute in improving the best solution. The improved PSO-DM algorithm is applied to the IEEE 33 bus system under four cases: the base case without DG and scenarios with 2, 3 and 4 DG units. The objective function includes active power loss minimization and total voltage deviation. Results. The 4-DG configuration significantly improves system performance: active power losses decrease from 210.67 kW to 53.9 kW (74.4 % reduction), reactive losses drop from 142.84 kVAr to 38.42 kVAr (73.1 % reduction), the minimum bus voltage rises from 0.9037 to 0.9741 p.u. and total voltage deviation decreases from 1.8037 p.u. to 0.5129 p.u. (71.6 % improvement). These results demonstrate that PSO-DM effectively balances exploration and exploitation, yielding superior DG allocation solutions. Scientific novelty. Integrating DM into PSO introduces a cooperative solution-refinement mechanism that enhances convergence speed and search accuracy. Practical value. The PSO-DM framework provides a reliable and computationally efficient tool for DG planning in modern smart distribution networks. References 22, tables 1, figures 3.

Development of a NARX neural network for a tribo-aero-electrostatic separator with rotating disk electrodes

Z. Ayache — 2026-01-02

Introduction. The exponential growth of waste electrical and electronic equipment (WEEE) requires efficient strategies for plastic waste management. Plastics, a major fraction of WEEE, represent both an environmental challenge due to low biodegradability and a valuable source of secondary raw materials. Problem. Tribo-aero-electrostatic separators with rotating disk electrodes offer a promising solution for fine plastic separation. However, their performance depends on multiple, nonlinear, and time-varying factors such as disk speed, voltage, and particle properties. These complex interactions make analytical modeling and stable process control difficult, limiting industrial implementation. The goal of this work is to develop a reliable dynamic model based on NARX neural networks capable of predicting the real-time evolution of key process variables such as recovered mass and particle charge. Methodology. The proposed NARX neural network learns temporal nonlinear relationships directly from experimental data, avoiding the need for explicit physical equations. Experiments were conducted on a synthetic 50:50 mixture of Acrylonitrile Butadiene Styrene (ABS) and Polystyrene (PS) particles (500-1000 μm) to assess model performance under varying disk speeds, voltages, and air flow rates. Results. The developed model accurately predicts the recovered mass and acquired charge of both ABS and PS over a wide range of operating conditions. The predictions show strong agreement with experimental measurements, maintaining low error levels even at parameter extremes. Scientific novelty. This work represents the first application of NARX neural networks to model the dynamic behavior of a two-rotating-disk tribo-aero-electrostatic separator. The approach captures essential time-dependent interactions that conventional static or analytical models fail to describe. Practical value. The NARX model exhibits high predictive accuracy and robustness across an extended operating domain (4–20 kV, 15–60 rpm, 7–9 m³/h), with errors limited to the 10^–3 g and 10^–3 µC ranges. These characteristics demonstrate its potential for real-time intelligent control and adaptive optimization of electrostatic separation processes in plastic waste recycling. References 39, tables 3, figures 9.

Performance improvement of parallel dual-star permanent magnet synchronous machines via type-2 fuzzy direct torque control with a single six-phase inverter

A. Bounab — 2026-01-02

Introduction. The growing need for efficient and high-performance electric drive systems has led to increased research in advanced control strategies for multi-machine configurations. Among them, dual-star permanent magnet synchronous machines (DSPMSMs) connected in parallel to a single inverter offer a promising solution for applications requiring high reliability and precise control. Problem. Conventional direct torque control (DTC) strategies, typically relying on PI controllers, suffer from significant torque and flux ripples, which negatively impact system efficiency and dynamic response. Moreover, these traditional controllers face challenges in handling parameter variations and external disturbances, limiting their applicability in demanding environments. Goal. This study aims to enhance the performance of DSPMSM drive systems by improving speed regulation, minimizing torque and flux fluctuations, and increasing robustness against disturbances, thereby ensuring greater efficiency and stability. Methodology. To address these challenges, we propose a novel DTC strategy that replaces the conventional PI controller with a type-2 fuzzy logic controller (T2-FLC). This intelligent control approach leverages the adaptability of fuzzy logic to improve response accuracy and dynamic performance. The proposed methodology is validated through extensive simulations using MATLAB/Simulink, analyzing various operating conditions and comparing the performance with conventional DTC techniques. Results. Simulation results confirm that the T2-FLC-based DTC significantly reduces torque and flux ripples while ensuring precise speed regulation. The proposed approach also demonstrates improved robustness against disturbances and parameter variations, outperforming traditional PI-based DTC in terms of efficiency and control accuracy. Scientific novelty. This research introduces an innovative application of T2-FLC in DTC for parallel-connected DSPMSMs, offering a novel control strategy that effectively mitigates the drawbacks of conventional methods. The integration of T2-FLC into the DTC framework provides enhanced adaptability and superior performance, distinguishing this study from existing works. Practical value. The proposed control strategy enhances the reliability, efficiency, and stability of DSPMSM-based drive systems, making it well-suited for high-performance applications such as railway traction, electric vehicles, and industrial automation. By improving control precision and robustness, this approach contributes to the advancement of intelligent drive technologies in modern electric propulsion systems. References 39, tables 4, figures 16.

Advanced control of twin rotor multi-input multi-output systems using seagull optimization for linear quadratic regulator tuning

H. Mostefaoui — 2026-01-02

Introduction. During the past decade, advanced control of complex multi-input multi-output (MIMO) systems has been a sustained focus owing to their growing use in aerospace and robotic platforms. The twin rotor MIMO system (TRMS) serves as a helicopter-like benchmark system for testing advanced control techniques. Its nonlinear behavior and significant cross-coupling render it difficult to control using traditional methods. Problem. The TRMS features strong nonlinear dynamics and cross-coupling effects that challenge conventional control methods. Manual tuning of control parameters often results in suboptimal performance and reduced robustness. The goal of this study is to optimize the linear quadratic regulator (LQR) weighting matrices Q and R for the TRMS using the seagull optimization algorithm (SOA) to improve transient performance, minimize overshoot, and accelerate stabilization in both pitch and yaw compared to classical LQR tuning. Methodology. The new approach integrates the SOA with LQR control theory. The SOA determines the best values of Q and R matrices by minimizing a cost function defined by system performance metrics. SOA-optimized LQR is evaluated through simulations and contrasted with the classical LQR under identical conditions. Population size is 50 agents with a maximum of 100 iterations to achieve convergence. Results. Simulation results show that the SOA-optimized LQR has a remarkable improvement in the system’s time response. In comparison to the classical LQR, these results provide a shorter settling time from 7.35 s to 5.34 s (≈28 %), decreases overshoot (≈3 % vs. 30 % open loop), increases damping, and reduces oscillations. The pitch and yaw angle responses across several control schemes clearly demonstrate the superior performance of the proposed optimization technique. Scientific novelty. This work demonstrates, for the first time, the use of SOA for optimal tuning of LQR in a TRMS benchmark. It opens new avenues to enhance the performance of high-order nonlinear systems, pointing toward more accurate and stable control techniques in industrial and aerospace engineering fields. Practical value. The technique provides an efficient method to enhance the functionality of complex nonlinear systems without requiring manual tuning, and it has potential applications in the industrial and aerospace areas. References 38, tables 3, figures 4.

Finite-time robust position tracking control for DC motors under uncertain dynamics

Q. B. Nguyen — 2026-01-02

Introduction. This study proposes a finite-time robust control law for position tracking of a DC motor under conditions of model uncertainty and external disturbances. The motor operates through a pulse-width modulation (PWM) unit and an H-bridge power circuit, aiming to achieve finite-time position tracking while minimizing the effects of model uncertainties and external disturbances. Problem. The main challenge lies in achieving accurate and rapid position and speed regulation for the DC motor while maintaining high performance, despite model inaccuracies and external disturbances. The goal of this paper is to design a robust finite-time position tracking control law for a DC motor based on the differential geometric approach, ensuring high tracking accuracy and control efficiency in the presence of disturbances and parameter uncertainties. Scientific novelty. The integration of finite-time control based on a virtual system, diffeomorphism transformation, and disturbance compensation introduces an innovative solution for DC motor position tracking under incomplete modeling and external perturbations. Methodology. The study employs the differential geometric method to construct a virtual system with finite-time characteristics and uses Lyapunov theory to prove global stability in the presence of uncertainties and disturbances. A finite-time virtual system is proposed after analyzing the incomplete dynamic model of the DC motor. Results. To validate the proposed approach, MATLAB simulations were conducted and compared with a conventional sliding mode controller. The results demonstrate improved settling time and robustness of the proposed method in DC motor position tracking. The findings confirm that the proposed controller provides intuitive and precise control, accurate position tracking, and enhanced performance regulation. It also exhibits strong robustness against model uncertainties and external disturbances. The practical value of the proposed method is considerable, as it offers a reliable and efficient position control scheme for DC motors using PWM. The method ensures precise position control and robust performance under varying conditions and external interferences, making it well-suited for real-world DC motor control applications. References 23, tables 1, figures 12.

An integrated series active power filter combined with a PV-battery system based on a fuzzy logic controller to enhance power quality for various linear and non-linear loads

B. M. Anwer — 2026-01-02

Introduction. Rapid capacity development and the incorporation of new loads are adding complexity to the distribution power system. As a result, the distribution system faces additional power quality issues, particularly with increasingly sensitive equipment and distributed generation. Problem. Modern power systems face escalating power quality degradation due to non-linear loads. Voltage disturbances (sags, swells) and harmonic distortions directly affect the sensitive equipment, causing significant economic losses. The goal of this work is to design, model, and evaluate series active power filters (SAPFs) integrated with energy management for an independent solar storage system, using a multi-stage DC-DC converter. The objective focuses on mitigating voltage harmonics and grid disturbances resulting from diverse loads (linear, non-linear, and combined) and integrating renewable energy (PV). Control is achieved through an intelligent fuzzy logic controller (FLC) and a PI controller to ensure a stable DC voltage and reduce the total harmonic distortion (THD) of the voltage to less than 5 %. Methodology. This study models and analyzes a unique SAPF configuration integrated with a PV-battery storage system utilizing MATLAB/Simulink. Outcomes of the proposed control, wherever the FLC regulates the DC-link voltage reference signals utilize the instantaneous reactive power theory. The suggested methodology entails simulation studies across four scenarios: an analysis of performance to keep voltage components and a comparison of the proposed SAPF performance with existing research on linear, non-linear, and combined loads. Results. Simulation results show the effectiveness of the control approach in mitigating the voltage THD level to less than 5 % under various operating conditions that included the main supply voltage and loads, which satisfies the international PQ standards (IEEE Std. 519). The scientific novelty lies in the combination of a new 3-phase SAPF with a PV-battery system by FLC and a cascaded DC/DC converter. This allows effective voltage disturbance and harmonic compensation in various load situations without conventional transformers. Practical value. This research offers a robust solution for power quality problems in modern grids, reducing losses by ensuring stable, no-distortion power for sensitive industrial loads across varied operating conditions. References 46, tables 3, figures 19.

Association smooth-pole dual open-end windings permanent magnet synchronous machine with cascaded 2-level inverters for improved performances

A. Nayli — 2026-01-02

Introduction. Power segmentation is an increasingly important priority in high-power industrial drive applications that utilize AC machines. Problem. To improve the dynamic performance, reliability and power segmentation of drive systems in high-power applications (above the megawatt range), it’s advantageous to replace a single high-power converter with several low-power converters. This principle is applied to the combination of AC machines and inverter structures. Goal. The authors propose a novel dual open-end windings permanent magnet synchronous machine. This machine reduces the required size of the power supply inverters while also improving dynamic performances and lifespan. Its power supply using 2-levels cascading inverters, further enhances these performances. Methodology. For this study, the mathematical model of the system in the Park reference frame is introduced and validated using the MATLAB/Simulink environment. First, simulation results are presented for the proposed machine supplied by four conventional two-level inverters based on the pulse width modulation technique. Next, the new machine is fed by four multilevel converters, with each converter consisting of two two-level inverters. To further demonstrate the benefits of this converter structure, the authors then use a configuration with three cascaded two-level inverters. The results demonstrate that the use of the new machine with conventional two-level inverters ensures power segmentation and improves the quality of the voltage, stator current, and torque. Furthermore, associating this same machine with cascaded multilevel inverter structures significantly enhances dynamic performance and reliability. The scientific novelty lies in the synergy achieved by integrating the novel synchronous machine with the cascaded two-level inverters, enabling the system to simultaneously surpass conventional limitations in both performance and reliability. Practical value. A simulation model of the novel dual open-end winding permanent magnet synchronous machine was implemented to validate the superior performance achieved with cascaded multilevel inverter structures for voltage supply compared to conventional two-level inverters. References 19, table 2, figures 17.

Numerical study of particles trajectories in a multifunctional electrostatic separator powered by photovoltaic system

N. Guettaf — 2026-01-02

Introduction. Electrostatic separation is a growing technology in the recycling industry. It is an effective technology for processing plastics and metallic materials in the form of granular mixtures or fine powders from waste electrical and electronic equipment. Problem. Understanding the various physical phenomena occurring in the separation zone is crucial for improving the efficiency of electrostatic separation devices. This has led to the adoption of efficient and reliable numerical models for simulating particle trajectories. The goal of the work is to represent graphically the trajectories of two insulating charged polypropylene particles of different sizes (2 mm and 4 mm) in the multifunctional electrostatic separator powered by photovoltaic (PV) system use a multipoint electrodes as charging device employing numerical simulation and demonstrate its effectiveness and reliability for the study of particles trajectories by integrating PV panels as a power source for electrostatic separators according to the recommendations of the new energy system. Methodology. Using the Euler-Cromer method as numerical model to solve the equation of motion of the particles. This method was based on the calculation of the electric field intensity, which is done by the COMSOL Multiphysics software, which uses the finite element method (FEM). The numerical simulation was carried out using MATLAB software by varying the voltage applied to the active electrodes of the multifunctional electrostatic separator suggested, and the distance between them, taking into account the influence of electrostatic and mechanical forces on the charged insulating particles as they pass through the separation zone. The results were showed that the numerical model used is an effective and reliable tool for the study of particles trajectories. Scientific novelty of this work is to integrate PV panels as the main low-voltage energy source at the input of the high-voltage generator supplying the electrostatic separator with an optimal voltage of 30 kV. In addition, this numerical study has used electrostatic forces, gravitational forces, and dynamic forces simultaneously. Practical value. The numerical simulation was contributed to a thorough understanding of various physical phenomena occurring in the separation zone and was considered a tool to validate experimental results. References 31, tables 2, figures 14.