Browsing by Author "Aydemir, Mehmet Timur"

Now showing 1 - 13 of 13

Citation - WoS: 70
Citation - Scopus: 91
A Comprehensive Review on Wireless Capacitive Power Transfer Technology: Fundamentals and Applications
(IEEE-Inst Electrical Electronics Engineers Inc, 2022) Erel, Mehmet Zahid; Bayindir, Kamil Cagatay; Aydemir, Mehmet Timur; Chaudhary, Sanjay K.; Guerrero, Josep M.; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Capacitive power transfer (CPT) technology is becoming increasingly popular in various application areas. Due to its limitations, such as low frequency, low coupling capacitance, and the high voltage stress on metal plates, the studies on high power CPT applications fell behind previously. Therefore, the wideband gap (WBG) semiconductor devices and the compensation topologies are further adopted to tackle these limitations. The main purpose of the paper is to review CPT applications in terms of performance parameters, advantages, disadvantages, and also challenges. Initially, the basic principles of CPT technology are examined, which cover compensation topologies, coupler structures, transfer distance, power electronic components, and system control methods. Then, CPT applications are evaluated for performance parameters (i.e., power level, operation frequency, system efficiency, transfer distance) along with compensation types, inverter types, and coupler types. The applications are categorized into six main groups according to industrial topics as safety, consumer electronics, transport, electric machines, biomedical, and miscellaneous. Herein, power level changes from mu W to kW ranges, the operation frequency varies from 100s of kHz to 10s of MHz ranges as well. The maximum system efficiency is recorded as 97.1 %. The transfer distance varies from mu m range to 100s of mm ranges. The full-bridge inverter topology and four-plate coupler structure are noticeable in CPT applications. Finally, advantages, disadvantages, and challenges of CPT applications are evaluated in detail. This review is expected to serve as a reference for researchers who study on CPT systems and their applications.
Citation - WoS: 2
Citation - Scopus: 3
High-Speed and Area-Efficient Arithmetic and Logic Unit Architecture Using Quantum-Dot Cellular Automata for Digital Signal Processing
(Elsevier, 2025) Zohaib, Muhammad; Navimipour, Nima Jafari; Aydemir, Mehmet Timur; Ahmadpour, Seyed-Sajad; Computer Engineering; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Signal processing has significantly influenced our lives in many domains, including telecommunications, education, healthcare, industry, and security. The efficiency of signal processing heavily relies on the Arithmetic and Logic Unit (ALU), which stands as an essential hardware component. In addition, ALU is a fundamental part of a central processing unit (CPU), leading to fundamental operations inside the processor. However, the growing demand for small, robust hardware systems has led researchers to create nano-electronic technologies under consideration. One of the leading technologies in this field is Quantum-dot cellular automata (QCA), which demonstrates promising value as a possible alternative to complementary metal-oxide-semiconductor (CMOS) designs since it enables compact circuit designs with minimal power consumption. The existing QCA-based ALU designs face limitations in cell count density together with high occupied area and high delay, which reduces their performance for real-time signal processing. This research presents a 1-bit ALU through a QCA-optimized approach for DSP applications. QCADesigner is used to validate and verify all proposed designs. Results show a statistically significant improvement in cell count reduction of 46.84 % and a total occupied area of 64.28 % lower than the most advanced version published to date.
Citation - WoS: 34
Citation - Scopus: 46
Inductive Power Transfer for Electric Vehicle Charging Applications: a Comprehensive Review
(Mdpi, 2022) Aydin, Emrullah; Aydemir, Mehmet Timur; Aksoz, Ahmet; El Baghdadi, Mohamed; Hegazy, Omar; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Nowadays, Wireless Power Transfer (WPT) technology is receiving more attention in the automotive sector, introducing a safe, flexible and promising alternative to the standard battery chargers. Considering these advantages, charging electric vehicle (EV) batteries using the WPT method can be an important alternative to plug-in charging systems. This paper focuses on the Inductive Power Transfer (IPT) method, which is based on the magnetic coupling of coils exchanging power from a stationary primary unit to a secondary system onboard the EV. A comprehensive review has been performed on the history of the evolution, working principles and phenomena, design considerations, control methods and health issues of IPT systems, especially those based on EV charging. In particular, the coil design, operating frequency selection, efficiency values and the preferred compensation topologies in the literature have been discussed. The published guidelines and reports that have studied the effects of WPT systems on human health are also given. In addition, suggested methods in the literature for protection from exposure are discussed. The control section gives the common charging control techniques and focuses on the constant current-constant voltage (CC-CV) approach, which is usually used for EV battery chargers.
Investigation of External Factors for Wireless Capacitive Power Transfer Systems
(Univ Osijek, Tech Fac, 2023) Erel, Mehmet Zahid; Bayindir, Kamil Cagatay; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Capacitive power transfer (CPT) technology has gained more and more importance in recent years. This paper investigates the effects of temperature and relative humidity on CPT system performance. The conventional four-plate horizontal and vertical coupler structures are built to observe the variations of coupling capacitances under external factors. The pressure of the coupler ambient is kept constant, and the effects of temperature and relative humidity are reviewed separately. The different temperature (25 - 105 & DEG;C) and relative humidity (43 - 80% RH) levels are reviewed in these scenarios. The obtained results indicate that the values of coupling capacitances are inversely proportional to the temperature level, whereas the values of coupling capacitances are directly proportional to the relative humidity level. In addition, the visible changes happen in coupling capacitances after 45 & DEG;C and 55 & DEG;C for horizontally and vertically arranged four-plate coupler structures, respectively. It is also observed that relative humidity level becomes a critical point after 60% RH for both coupler structures. Among the coupling capacitances, the main capacitances are the most affected during the variations for both couplers. This study is expected to be a reference for the researchers on external factors in CPT systems.
Citation - WoS: 1
A Load Adaptive Cascade Pi Controller for Buck Converters Operating in Wide Load Range in Cathodic Protection Systems
(IEEE, 2021) Ozdemir, Mehmet Akif; Simsek, Oguz; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; Advertising; 04. Faculty of Communication; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
This paper proposes a simple cascade PI controller for Buck converter to be used in impressed current cathodic protection (ICCP) systems which aim to operate in wide voltage and current ranges for any load condition. The Buck converter with cascade controller structure is a frequently used topology in ICCP systems to prevent buried steel pipelines from corrosion. Changes in the environment in which the pipe is embedded force the converter to operate at wide load and voltage ranges. However, in average current mode controllers, the gain of the current loop varies significantly with the load. At light loads, the inner current loop slows down dramatically and may stay behind the outer voltage loop. In order to solve these issues and to maintain the regulation of the pipeline voltage and the average load current, this paper presents a simple cascade PI controller whose coefficients are adapted to the changing load. The small signal analysis of the Buck converter in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM) is performed and variables determining the transfer characteristics are examined. For the proposed controller, a design criteria based on circuit parameters have been established. With the parameters obtained by the proposed method, a sample cascade controller is designed and compared with classical PI controller in simulation. Also, a digitally controlled 100-W converter prototype is built to validate the performance.
A Modified Plate Design for Capacitive Wireless Power Transfer Systems
(IEEE, 2025) Alhayek, Ahmed; Ozdemir, Mehmet Akif; Erel, Mehmet Zahid; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; Advertising; 04. Faculty of Communication; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
The share of capacitive wireless power transfer in recent wireless power transfer research has been increasing. The advantage of these systems mainly comes from their simple structures. The power is transferred between the plates, and there is no need for magnetic shielding as there is no magnetic field involved. The transferred energy depends on the capacitance of the plates, and increasing the effective area of the plate without changing its size can be effective. This paper proposes a simple technique to increase the effective area of plates. Basically, the effective area is increased by grooving the surface, like the fins of heat sinks. The proposed technique has been tested on a four-plate horizontal structure. The results show that the proposed method can be effective.
Citation - WoS: 12
Citation - Scopus: 11
A Nano-Scale Design of Arithmetic and Logic Unit for Energy-Efficient Signal Processing Devices Based on a Quantum-Based Technology
(Springer, 2025) Zohaib, Muhammad; Navimipour, Nima Jafari; Aydemir, Mehmet Timur; Ahmadpour, Seyed-Sajad; Computer Engineering; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Signal processing had a significant impact on the development of many elements of modern life, including telecommunications, education, healthcare, industry, and security. The semiconductor industry is the primary driver of signal processing innovation, producing ever-more sophisticated electronic devices and circuits in response to global demand. In addition, the central processing unit (CPU) is described as the "brain" of a computer or all electronic devices and signal processing. CPU is a critical electronic device that includes vital components such as memory, multiplier, adder, etc. Also, one of the essential components of the CPU is the arithmetic and logic unit (ALU), which executes the arithmetic and logical operations within all types of CPU operations, such as addition, multiplication, and subtraction. However, delay, occupied areas, and energy consumption are essential parameters in ALU circuits. Since the recent ALU designs experienced problems like high delay, high occupied area, and high energy consumption, implementing electronic circuits based on new technology can significantly boost the performance of entire signal processing devices, including microcontrollers, microprocessors, and printed devices, with high-speed and low occupied space. Quantum dot cellular automata (QCA) is an effective technology for implementing all electronic circuits and signal processing applications to solve these shortcomings. It is a transistor-less nanotechnology being explored as a successor to established technologies like CMOS and VLSI due to its ultra-low power dissipation, high device density, fast operating speed in THz, and reduced circuit complexity. This research proposes a ground-breaking ALU that upgrades electrical devices such as microcontrollers by applying cutting-edge QCA nanotechnology. The primary goal is to offer a novel ALU architecture that fully utilizes the potential of QCA nanotechnology. Using a new and efficient approach, the fundamental gates are skillfully utilized with a coplanar layout based on a single cell not rotated. Furthermore, this work presents an enhanced 1-bit and 2-bit arithmetic logic unit in quantum dot cellular automata. The recommended design includes logic, arithmetic operations, full adder (FA) design, and multiplexers. Using the powerful simulation tools QCADesigner, all proposed designs are evaluated and verified. The simulation outcomes indicates that the suggested ALU has 42.48 and 64.28% improvements concerning cell count and total occupied area in comparison to the best earlier single-layer and multi-layer designs.
Citation - WoS: 6
Citation - Scopus: 9
A New Capacitive Coupler Design for Wireless Capacitive Power Transfer Applications
(Elsevier - Division Reed Elsevier India Pvt Ltd, 2023) Erel, Mehmet Zahid; Bayindir, Kamil Cagatay; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Capacitive power transfer (CPT) technology has become a promising alternative solution for wireless charging applications. This paper proposes a novel coupler design to form a resonant capacitor by inserting dielectric material between two bent metal plates for each primary and secondary circuit. The main purpose of the proposed coupler is to eliminate the external capacitors and solve the low coupling capacitance for CPT applications. A comparison to the conventional four-plate coupler is presented, which shows specifically higher coupling capacitance, lower required inductance, and lower cost. Finally, the effectiveness of the proposed coupler structure is verified by simulation and experimental results. (c) 2023 Karabuk University. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Novel Designs of Fault-Tolerant Nano-Scale Circuits for Digital Signal Processing Using Quantum Dot Technology
(Elsevier, 2026) Zohaib, Muhammad; Navimipour, Nima Jafari; Aydemir, Mehmet Timur; Ahmadpour, Seyed-Sajad
Digital signal processing (DSP) is a crucial engineering field dedicated to the processing and analysis of digital signals. DSP is particularly significant in critical sectors such as telecommunications, medical imaging, and secure communications, where it demands high accuracy, reliability, and real-time performance. In addition, the fault-tolerant (F-T) Arithmetic and Logic Unit (ALU) provides a fundamental building block of DSP architectures, enabling the accurate implementation of arithmetic and logical functions that are essential for advanced computational tasks. However, traditional ALUs were designed using complementary metal-oxide semiconductors (CMOS) and very large-scale integration (VLSI), which led to several challenges, such as high energy consumption, high occupied area, and slow operating speed. These limitations can be effectively addressed through nanotechnology, specifically quantum-dot cellular automata (QCA), which offers high speed, reduces occupying area, and has low power consumption. Accordingly, this paper proposes a QCA-based ALU circuit for DSP applications. The proposed designs integrate an F-T full adder (FA), a QCA-based multiplexer (MUX), and an ALU circuit to enhance performance and efficiency for DSP applications. The validation and verification of all suggested designs are performed using the simulation tool QCADesigner.
Citation - WoS: 2
Citation - Scopus: 2
A Novel Hybrid Coil Design and Implementation for Wireless Power Transfer Systems
(Edp Sciences S A, 2024) Pashaei, Ali; Aydin, Emrullah; Ozdemir, Mehmet Akif; Kosesoy, Yusuf; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; Advertising; 04. Faculty of Communication; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Wireless Power Transfer (WPT) has been drawing a lot of attention in the last ten years parallel with the market increase in electric vehicles. Although conductive charging methods are still the preferred ones, WPT-based charging systems are used as clean and flexible alternatives. At the center of these systems are the transmitting and receiving coils, and different coil types have been proposed in the literature. This study proposes a square-hexagonal hybrid coil structure to increase magnetic coupling by shaping the magnetic field. In addition, this design aims to minimize the coupling coefficient variation for misaligned coils which is one of the most significant problems in WPT systems. A 3D model of the coils was created and analyzed using ANSYS, Maxwell software. Compared to the conventional square coil structure the coupling coefficient of the proposed structure is less affected by misalignment on the x and y axes, and as a result, it has a better efficiency. In addition, a WPT system operating at 50 W, 85-kHz is designed and tested in a laboratory environment. The FEA analyses and experimental application results largely overlap, and accordingly, the coil-to-coil efficiency of our WPT system was 93.5% and the overall efficiency of the system was 87%.
A Novel Multiscale Graph Signal Processing and Network Dynamics Approach to Vibration Analysis for Stone Size Discrimination via Nonlinear Manifold Embeddings and a Convolutional Self-Attention Model
(Springer Wien, 2025) Mirza, Fuat Kaan; Oz, Usame; Hekimoglu, Mustafa; Aydemir, Mehmet Timur; Pural, Yusuf Enes; Baykas, Tuncer; Pekcan, Onder; Electrical-Electronics Engineering; Industrial Engineering; Molecular Biology and Genetics; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Understanding nonlinear dynamics is critical for analyzing the hidden complexities of vibrational behavior in real-world systems. This study introduces a graph-theoretic approach to analyze the complex nonlinear temporal patterns in vibrational signals, utilizing the Tri-Axial Vibro-Dynamic Stone Classification dataset. This dataset captures high-resolution acceleration signals from controlled stone-crushing experiments, providing a unique opportunity to investigate temporal dynamics associated with distinct stone sizes. A 12-level Maximal Overlap Discrete Wavelet Transform is employed to perform multiscale signal decomposition, enabling the construction of transition graphs that encode transient and stable structural characteristics. Conceptually, transition graphs are analyzed as dynamic networks to uncover the interactions and temporal patterns embedded within vibrational signals. These networks are studied using a comprehensive suite of complexity metrics derived from information theory, graph theory, network science, and dynamical systems analysis. Metrics such as Shannon and Von Neumann's entropy evaluate signal dynamics' stochasticity and information retention. At the same time, the spectral radius measures the network's stability and structural robustness. Lyapunov exponents and fractal dimensions, informed by chaos theory and fractal geometry, further capture the degree of nonlinearity and temporal complexity. Complementing these dynamic measures, static network metrics-including the clustering coefficient, modularity, and the static Kuramoto index-offer critical discernment into the network's community structures, synchronization phenomena, and connectivity efficiency. Manifold learning techniques address the high-dimensional feature space derived from complexity metrics, with UMAP outperforming ISOMAP, Spectral Embedding, and PCA in preserving critical data structures. The reduced features are input into a convolutional self-attention model, combining localized feature extraction with long-term sequence modeling, achieving 100% classification accuracy across stone-size categories. This study presents a comprehensive framework for vibrational signal analysis, integrating multiscale graph-based representations, nonlinear dynamics quantification, and UMAP-based dimensionality reduction with a convolutional self-attention classifier. The proposed approach supports accurate classification and contributes to the development of data-driven tools for automated diagnostics and predictive maintenance in industrial and engineering contexts.
Solar Energy-Powered Wireless Charging System for Three-Wheeled E-Scooter Applications
(Pergamon-elsevier Science Ltd, 2025) Erel, Mehmet Zahid; Ozdemir, Mehmet Akif; Aydemir, Mehmet Timur; Electrical-Electronics Engineering; Advertising; 04. Faculty of Communication; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Wireless power transfer (WPT) is a remarkable charging technology that addresses the range limitations and complexity of light electric vehicles. This study presents a novel approach to a solar-powered WPT system designed for three-wheeled e-scooter applications. The proposed system offers compact, lightweight, and costeffective solution with a ferrite-less structure and a series-series (SS) compensation topology, resulting in enhanced system efficiency and adaptability. The compact and efficient converters are designed to enhance performance and reduce system size. A Proportional-Integral (PI) controlled Perturb and Observe (P&O) maximum power point tracking (MPPT) method is implemented to optimize energy extraction from three solar panels. The design is validated through comprehensive simulations and demonstrates a superior dynamic response over the Incremental Conductance MPPT (ICM) method. Performance tests confirm the reliability of the experimental prototype, achieving a system efficiency of 88.5 % at 300-W output power over a 100 mm transfer distance under fully aligned condition. Comparative analyses with existing solar-powered e-cycle systems highlight the proposed design's superiority in efficiency, cost-effectiveness, and adherence to safety standards. The results indicate that the proposed design enhances sustainable urban transportation by reducing carbon emissions and decreasing reliance on fossil fuels, facilitating the wider integration of renewable energy sources.
Yüksek Da Gerilim Uygulamaları için Empedans Kaynaklı Yükseltici Çevirici Tasarımı
(2023) Aydemir, Mehmet Timur; Dağ, Bülent; Özdemir, Mehmet Akif; Aydın, Emrullah; Tamyürek, Bünyamin; Electrical-Electronics Engineering; 05. Faculty of Engineering and Natural Sciences; 01. Kadir Has University
Bu çalışmada yüksek DA gerilimli bir güç kaynağında kullanılmak üzere yüksek kazançlı yeni nesil bir empedans kaynaklı yükseltici çeviricinin güç katı tasarımı yapılmıştır. Ele alınan empedans kaynaklı çevirici yeni geliştirilmiş bir topoloji olup, çeviricinin temel çalışma prensibi daha önceki bir çalışmada detaylı şekilde incelenmiştir. Bu çalışmada çeviricinin hedeflenen uygulamaya yönelik tasarımı için gereken gerilim-denge ve akım-denge eşitlikleri çıkarılmıştır ve bu eşitlikler kullanılarak uygun devre elemanları değerleri belirlenmiştir. Tasarlanan çeviricinin performansı Matlab-Simulink benzetim modeli ile doğrulanmıştır.