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Articles 1861 - 1890 of 1965
Full-Text Articles in Computer Sciences
Retinal Image Analysis Using Multidirectional Functors Based On Geodesic Conversions, Saleh Shahbeig
Retinal Image Analysis Using Multidirectional Functors Based On Geodesic Conversions, Saleh Shahbeig
Turkish Journal of Electrical Engineering and Computer Sciences
A retinal image contains vital information. Extracting these features is the first and most important step in the analysis of retinal images for various applications of medical or human recognition. In this study, a morphological-based blood vessel extraction algorithm using adaptive-local analysis from colored retinal images is proposed. In this algorithm, by applying the appropriate morphology functors and local histogram stretching on the retinal images, the brightness of the images is considerably uniformed. Furthermore, curvelet transform (CT) is used to enhance the retinal images by highlighting the edges of the images in various scales and directions and by the adaptive …
Recurrent Wavelet Neural Network Control Of A Pmsg System Based On A Pmsm Wind Turbine Emulator, Chih Hong Lin
Recurrent Wavelet Neural Network Control Of A Pmsg System Based On A Pmsm Wind Turbine Emulator, Chih Hong Lin
Turkish Journal of Electrical Engineering and Computer Sciences
A recurrent wavelet neural network (NN)-controlled 3-phase permanent magnet synchronous generator system (PMSG), which is direct-driven by a permanent magnet synchronous motor (PMSM) based on a wind turbine emulator, is proposed to control the output values of a rectifier (or AC to DC power converter) and inverter (or DC to AC power converter) in this study. First, a closed-loop PMSM drive control based on a wind turbine emulator is designed to generate the maximum power for the PM synchronous generator (PMSG) system according to different wind speeds. Next, the rotor speed of the PMSG, the DC bus voltage, and the …
Impact Of Plug-In Hybrid Electric Vehicle Charging/Discharging Management On A Microgrid, Kiamars Kaveh, Seyed Mehdi Hakimi, Seyed Masoud Moghaddas-Tafreshi, Fazllolah Naseri
Impact Of Plug-In Hybrid Electric Vehicle Charging/Discharging Management On A Microgrid, Kiamars Kaveh, Seyed Mehdi Hakimi, Seyed Masoud Moghaddas-Tafreshi, Fazllolah Naseri
Turkish Journal of Electrical Engineering and Computer Sciences
Plug-in hybrid electric vehicles (PHEVs) may replace conventional vehicles in most urban areas and populated cities due to their lower levels of air pollution compared to internal combustion engine (ICE) vehicles. PHEVs can increase the ability of residential complexes to participate in demand-side management, as well. This paper explores the potential of PHEVs as a flexible load in order to satisfy 2 main issues: increasing the penetration rate of renewable energy in a microgrid and increasing the load factor. In this study, 3 scenarios for managing PHEV charging and discharging are considered. The first scenario connects PHEVs to the grid …
Discovery Of Hydrometeorological Patterns, Mete Çeli̇k, Fi̇li̇z Dadaşer Çeli̇k, Ahmet Şaki̇r Dokuz
Discovery Of Hydrometeorological Patterns, Mete Çeli̇k, Fi̇li̇z Dadaşer Çeli̇k, Ahmet Şaki̇r Dokuz
Turkish Journal of Electrical Engineering and Computer Sciences
Hydrometeorological patterns can be defined as meaningful and nontrivial associations between hydrological and meteorological parameters over a region. Discovering hydrometeorological patterns is important for many applications, including forecasting hydrometeorological hazards (floods and droughts), predicting the hydrological responses of ungauged basins, and filling in missing hydrological or meteorological records. However, discovering these patterns is challenging due to the special characteristics of hydrological and meteorological data, and is computationally complex due to the archival history of the datasets. Moreover, defining monotonic interest measures to quantify these patterns is difficult. In this study, we propose a new monotonic interest measure, called the hydrometeorological …
Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare
Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare
Turkish Journal of Electrical Engineering and Computer Sciences
The performance of the state estimation (SE) depends on the accuracy of the received measured data, as well as the parameter data of the power system. In this paper, a new algorithm is proposed for the simultaneous identification and correction of measurement and branch parameter errors (series and shunt admittances) in the power system SE problem. The proposed method uses Lagrange multipliers for the identification and correction of branch parameter errors without the need for a-priori specification of suspect parameter vectors. Erroneous measurements and branch parameter values can be corrected using the proposed method to estimate the measurement and branch …
Shuffled Frog Leaping Algorithm Optimization For Ac--Dc Optimal Power Flow Dispatch, Abolfazl Rahiminejad, Arash Alimardani, Behrooz Vahidi, Seyed Hossein Hosseinian
Shuffled Frog Leaping Algorithm Optimization For Ac--Dc Optimal Power Flow Dispatch, Abolfazl Rahiminejad, Arash Alimardani, Behrooz Vahidi, Seyed Hossein Hosseinian
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a simple-implemented and reliable AC--DC optimal power flow (OPF) is proposed. Although high-voltage direct current (HVDC) transmission lines are being increasingly used in power systems, new optimization algorithms such as evolutionary and memetic algorithms, which never stick in local minimum, so far have not been implemented in the AC--DC OPF problem. An evolutionary algorithm known as the shuffled frog leaping algorithm (SFLA) is proposed in this paper to solve the OPF dispatch in an AC--DC power system (including both high-voltage alternating current and HVDC transmission lines). The implementation of the AC--DC OPF with these kinds of methods …
Multifunction Converter Based On Lyapunov Function Used In A Photovoltaic System, Trung Nhan Nguyen, An Luo
Multifunction Converter Based On Lyapunov Function Used In A Photovoltaic System, Trung Nhan Nguyen, An Luo
Turkish Journal of Electrical Engineering and Computer Sciences
The development of distributed generations (DGs) is essential to help solve energy crises and improve the reliability of electricity supplies. However, the involvement of a DG in a grid along with an increase of the nonlinear load will reduce the power quality. To solve this problem, we want the converter used in the DG to work flexibly, intelligently, and more accurately. To contribute to the improvement of quality of the DG, this paper proposes a multifunction converter (MFC) model. With the proposed model, the photovoltaic generator, which can be operated at harmonic suppression, and the power injection are more flexible …
Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül
Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül
Turkish Journal of Electrical Engineering and Computer Sciences
A new, simple, and effective control method is proposed for the position-based impedance and force control of a Stewart platform (SP). The control approach can be divided into 3 parts, namely position control in free space, impedance control in contact, and force control. An impedance filter is developed to achieve the desired behavior between the position and force. The gain of the filter is modified by a fuzzy logic proportional-integral-derivative controller. Kinematic and dynamic models of the SP are simulated in a MATLAB/Simulink environment. Several real-time experiments are conducted with the SP developed in our laboratory. The results of the …
Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu
Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a simple approach for intelligent modeling of the Henry factor (\alpha-alpha parameter, antiguiding factor, phase-amplitude coupling factor) or the so-called linewidth enhancement factor, which is an actual analysis and design parameter for semiconductor laser diodes and optical communication systems, is proposed based on the fuzzy logic (FL) phenomenon. The proposed FL-based model easily computes the Henry factor in terms of different wavelengths and injection current levels (i.e. the inputs of the model). The experimental data belong to a distributed feedback laser, obtained from amplified spontaneous emission spectra, which is among the techniques required for the characterization of …
Model-Based Robust Chaotification Using Sliding Mode Control, Aykut Kocaoğlu, Cüneyt Güzeli̇ş
Model-Based Robust Chaotification Using Sliding Mode Control, Aykut Kocaoğlu, Cüneyt Güzeli̇ş
Turkish Journal of Electrical Engineering and Computer Sciences
Chaos is a complex behavior of dynamical nonlinear systems that is undesirable in most applications and should be controlled; however, it is desirable in some situations and should be generated. In this paper, a robust chaotification scheme based on sliding mode control is proposed for model based chaotification. A continuous time single input observable system is considered such that it is subject to parameter uncertainties, nonlinearities, noises, and disturbances, which are all additive to the input and can be modeled as an unknown function but bounded by a known function. The designed dynamical state feedback control law forces the system …
Performance Evaluation Of The Wave Atom Algorithm To Classify Mammographic Images, Nebi̇ Gedi̇k, Ayten Atasoy
Performance Evaluation Of The Wave Atom Algorithm To Classify Mammographic Images, Nebi̇ Gedi̇k, Ayten Atasoy
Turkish Journal of Electrical Engineering and Computer Sciences
The most common type of cancer seen in women is breast cancer. To enable recovery from this severe disease, monitoring and early detection must be provided, and related precautions must be taken as a first step. During diagnosis, some cases may be overlooked due to fatigue and eyestrain, because the determination of abnormalities is a repetitive procedure. In this study, a computer-aided diagnosis (CAD) system, using the wave atom transform (WAT) algorithm and support vector machine (SVM), is proposed to evaluate mammography images. During the process, the region of interest (ROI) is defined before applying the method. The system includes …
A New Edge-Preserving Algorithm Based On The Cie- Lu'v' Color Space For Color Contrast Enhancement, Mohammad Zolfaghari, Mehran Yazdi
A New Edge-Preserving Algorithm Based On The Cie- Lu'v' Color Space For Color Contrast Enhancement, Mohammad Zolfaghari, Mehran Yazdi
Turkish Journal of Electrical Engineering and Computer Sciences
Image segmentation and edge detection are the most important presteps in machine vision, and their successfulness can affect the success of the next steps. In this paper, the performance of the Trahanias edge detector in different color spaces, such as RGB, YCbCr, HSI, and CIE Lu'v', is compared in order to find the best color space for image segmentation and edge detection. We then offer an efficient edge-preserving algorithm for color contrast enhancement in the CIE Lu'v' space. The proposed algorithm can increase the color contrast, which causes a remarkable improvement in image segmentation and edge detection in the CIE …
New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour
New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new throughput-based transmit antenna selection (AS) scheme is evaluated. First, a closed-form solution for the throughput rate of a multiple-input multiple-output (MIMO) system, with a truncated selective repeat automatic repeat request (TSR-ARQ) or selective repeat plus go-back-N automatic repeat request (SR+GBN-ARQ) protocol at the data link layer, is proposed. In addition, a throughput-based AS technique with adaptive modulation is also investigated. For this purpose, the throughput and packet error rates of a MIMO system with a transmit AS and TSR-ARQ protocol at the data link layer are analyzed. This study is conducted in 2 different cases. …
A Low-Order Nonlinear Amplifier Model With Distributed Delay Terms, Ahmet Hayretti̇n Yüzer, Şi̇mşek Demi̇r
A Low-Order Nonlinear Amplifier Model With Distributed Delay Terms, Ahmet Hayretti̇n Yüzer, Şi̇mşek Demi̇r
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a novel behavioral modeling technique for the characterization of memory effects of amplifiers is proposed. This characterization utilizes asymmetric intermodulation distortion (IMD) components, which are the result of a 2-tone excitation of a nonlinear amplifier. These asymmetric IMD components are represented basically by a power series, where each term in the series has its own time delay term. These time delay terms successfully justify the presence of asymmetry in the intermodulation components, which leads to the prediction of amplitude-to-amplitude and amplitude-to-phase distortions. The parameters of the model are extracted using 2-tone measurements. A 100-W peak power amplifier …
Expert Doctor Verdis: Integrated Medical Expert System, Aytürk Keleş
Expert Doctor Verdis: Integrated Medical Expert System, Aytürk Keleş
Turkish Journal of Electrical Engineering and Computer Sciences
Innovative medical technologies are developing day by day, as there is an important need for integrated medical expert systems (ESs) that will help to effectively manage and control diagnosis and treatment processes. These systems, with new approaches, have improved the experiences and capabilities of physicians to make the diagnosis of diseases. In this work, an integrated medical ES called Expert Doctor Verdis (Ex-Dr Verdis) is developed, which combines an advanced medical information system containing various medical services supported by information technologies, with ES capabilities in a single system. This system is also one kind of decision support system. Implementation of …
Comparison Of Different Methods For Determining Diabetes, Mehmet Recep Bozkurt, Ni̇lüfer Yurtay, Zi̇ynet Yilmaz, Cengi̇z Sertkaya
Comparison Of Different Methods For Determining Diabetes, Mehmet Recep Bozkurt, Ni̇lüfer Yurtay, Zi̇ynet Yilmaz, Cengi̇z Sertkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the Pima Indian Diabetes dataset was categorized with 8 different classifiers. The data were taken from the University of California Irvine Machine Learning Repository's web site. As a classifier, 6 different neural networks [probabilistic neural network (PNN), learning vector quantization, feedforward networks, cascade-forward networks, distributed time delay networks (DTDN), and time delay networks], the artificial immune system, and the Gini algorithm from decision trees were used. The classifier's performance ratios were studied separately as accuracy, sensitivity, and specificity and the success rates of all of the classifiers are presented. Among these 8 classifiers, the best accuracy and …
A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin
A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin
Turkish Journal of Electrical Engineering and Computer Sciences
Due to the electric scooter with nonlinear uncertainties, e.g., nonlinear friction force of the transmission belt, the linear controller was made to disable speed tracking control. In order to overcome this problem, a novel hybrid recurrent wavelet neural network (NHRWNN) control system is proposed to control for a permanent-magnet synchronous motor-driven electric scooter in this study. The NHRWNN control system consists of a supervised control, a recurrent wavelet neural network (RWNN), and a compensated control with adaptive law. According to the Lyapunov stability theorem and the gradient descent method, the on-line parameter training methodology of the RWNN can be derived …
An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci
An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a sensorless speed estimation method with an artificial neural network for squirrel cage induction motors is presented. Motor current is generally used for sensorless speed estimation. Rotor slot harmonics are available in the frequency spectrum of the current. The frequency components of these determined harmonics are used to estimate the speed of the motor in which the number of rotor slots is given. In the literature, individual algorithms have been used to calculate the speed from the slot harmonics. Unlike the literature, in the proposed method, an artificial neural network is used to extract the speed from …
A Control Scheme Employing An Adaptive Hysteresis Current Controller And An Uncomplicated Reference Current Generator For A Single-Phase Shunt Active Power Filter, Hüseyi̇n Doğan, Ramazan Akkaya
A Control Scheme Employing An Adaptive Hysteresis Current Controller And An Uncomplicated Reference Current Generator For A Single-Phase Shunt Active Power Filter, Hüseyi̇n Doğan, Ramazan Akkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In recent years, active power filters (APFs) have become popular because of their excellent current harmonics and reactive power mitigation ability. The performance of the APF is directly related to the selected control strategy, which is mainly divided into 2, the reference current generation and current control. Most of the reference current generation methods are very complicated and require precise mathematical expressions. Moreover, being the most preferred current control method, conventional hysteresis controllers have a fixed bandwidth, which causes different total demand distortion values under different load conditions. In this study, a novel control scheme for a single-phase shunt APF …
Stability Analysis Of Multimachine Thermal Power Systems Using The Nature-Inspired Modified Cuckoo Search Algorithm, Shivakumar Rangasamy, Panneerselvam Manickam
Stability Analysis Of Multimachine Thermal Power Systems Using The Nature-Inspired Modified Cuckoo Search Algorithm, Shivakumar Rangasamy, Panneerselvam Manickam
Turkish Journal of Electrical Engineering and Computer Sciences
The stability of modern interconnected thermal power systems is greatly affected by the presence of low-frequency inertial oscillations in the system, due to various forms of disturbances experienced. This paper provides an efficient damping solution to these oscillations based on nature-inspired modified cuckoo search algorithm-based controller design. The proposed controller design is formulated as a parameter optimization problem based on damping ratio and time-domain error deviations. The effectiveness of the proposed damping controller design is illustrated by performing the nonlinear time domain simulations of the test multimachine power systems under various operating conditions and disturbances. Moreover, an exhaustive comparative stability …
Application Of Hilbert--Huang Transform And Support Vector Machine For Detection And Classification Of Voltage Sag Sources, Alireza Foroughi, Ebrahim Mohammadi, Saeid Esmaeili
Application Of Hilbert--Huang Transform And Support Vector Machine For Detection And Classification Of Voltage Sag Sources, Alireza Foroughi, Ebrahim Mohammadi, Saeid Esmaeili
Turkish Journal of Electrical Engineering and Computer Sciences
Power quality disturbances, including voltage sag, swell, harmonics, flicker, and notch, are one of the main concerns for industries and electrical equipment. Among these disturbances, voltage sag, due to its irrecoverable economic effects on industries, is particularly important. In this paper, the detection and classification of voltage sag sources containing motor starting, short circuit, transformer energizing, and the reacceleration of motors after fault clearance using the Hilbert--Huang transform (HHT) and support vector machine (SVM) are studied. A voltage sag waveform includes several oscillating modes; for separating these oscillating modes, which are called intrinsic mode functions (IMFs), empirical mode decomposition is …
New Approach Using Structure-Based Modeling For The Simulation Of Real Power/Frequency Dynamics In Deregulated Power Systems, Mostafa Eidiani, Hossein Zeynal
New Approach Using Structure-Based Modeling For The Simulation Of Real Power/Frequency Dynamics In Deregulated Power Systems, Mostafa Eidiani, Hossein Zeynal
Turkish Journal of Electrical Engineering and Computer Sciences
Load frequency control (LFC) is one of the significant ancillary services in the electricity markets. The major concerns with LFC models have long been their dynamic response and complexity, as well as market price sensitivity. To cater to the complexity of the dynamic model that is introduced by the LFC and algebraic constraints by the transmission network, the differential-algebraic equation is transformed into a set of ordinary differential equations. This is done by differentiating the network constraints under a certain assumption that can be held throughout the system. To make the model suitable in a market environment, the real power …
Reliability-Based Maintenance Scheduling Of Generating Units In Restructured Power Systems, Mahmud Fotuhi Firuzabad, Farrokh Aminifar, Abbas Shahzadeh
Reliability-Based Maintenance Scheduling Of Generating Units In Restructured Power Systems, Mahmud Fotuhi Firuzabad, Farrokh Aminifar, Abbas Shahzadeh
Turkish Journal of Electrical Engineering and Computer Sciences
Maintenance scheduling of generating units in restructured power systems is a collaborative and interactive process between independent system operators (ISOs) and generating companies (GENCOs). The ISO should comply with GENCO maintenance preferences subject to targeted system reliability levels. This process might be multistage since the admission of all initial unit outage requests may threaten system reliability. Hence, the ISO accepts some proposals and determines alternatives for the remaining units. The GENCOs are then allowed to confirm the alternatives or revise them. In this paper the ISO problem of generating unit maintenance scheduling is tackled. The objective function is to minimize …
Optimal Reactive Power Flow Solution In Multiterminal Ac-Dc Systems Based On Artificial Bee Colony Algorithm, Faruk Yalçin, Uğur Ari̇foğlu
Optimal Reactive Power Flow Solution In Multiterminal Ac-Dc Systems Based On Artificial Bee Colony Algorithm, Faruk Yalçin, Uğur Ari̇foğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Active power loss optimization is one of the important goals in electrical power systems and it is provided by optimal reactive power flow (ORPF). In this study, a new approach for the solution of the ORPF in multiterminal AC-DC systems is proposed. This approach provides 3 main contributions. First, the convergence problem in the AC-DC power flow is solved. Second, the problem of getting stuck in local minima during the optimization process is overcome. Third, a better global optimum point is obtained for the ORPF. Active power loss optimization is implemented through the artificial bee colony (ABC) algorithm, which is …
Design And Realization Of A Welding Oscillator, Muci̇z Özcan
Design And Realization Of A Welding Oscillator, Muci̇z Özcan
Turkish Journal of Electrical Engineering and Computer Sciences
Welding is one of the most popular methods to combine metal pieces in manufacturing processes. Arc welding, among all welding techniques, is the most commonly used in manufacturing due to its cost and flexibility. During the manufacturing process, arc welding is either performed by an operator or by automatic tools such as welding oscillators. Using automatic tools has advantages over manual use, as the process will be faster, cheaper, and have less welding flaws. In this paper, a homemade welding oscillator and the method to manufacture it are presented. The presented welding oscillator can be manufactured for a very low …
A Reconfigurable Baseband Circuit Applied For Wimax Low-If Receivers, Xin Cheng, Guangjun Xie
A Reconfigurable Baseband Circuit Applied For Wimax Low-If Receivers, Xin Cheng, Guangjun Xie
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a reconfigurable baseband circuit for WiMAX low-IF receivers, including a complex filter and 2 automatic gain controllers (AGCs) for I and Q channels. Only by changing the capacitor values can the center and cutoff frequencies of the complex filter be adjusted simultaneously to realize the reconfigurability. Meanwhile, a novel one-step method to obtain fast gain settling of AGCs is proposed. The chip is fabricated in 0.13-\mu m CMOS technology, occupies 0.9 \times 1.3 mm^2, and consumes 14.8 mW of power with a 1.2-V power supply. The measurement results show a reconfigurable bandwidth of 2 K to 3.5/5/10 …
Comparison Of Ais And Fuzzy C-Means Clustering Methods On The Classification Of Breast Cancer And Diabetes Datasets, Seral Özşen, Rahi̇me Ceylan
Comparison Of Ais And Fuzzy C-Means Clustering Methods On The Classification Of Breast Cancer And Diabetes Datasets, Seral Özşen, Rahi̇me Ceylan
Turkish Journal of Electrical Engineering and Computer Sciences
Data reduction is an indispensable part of pattern classification processes in many cases. If the number of samples is excessive, sample reduction or data reduction algorithms can be used for an effective processing time and reliable successive results. Many methods have been used for data reduction. Fuzzy c-means is one of these methods and it is widely used in such applications as clustering algorithms. In this study, we applied a different clustering algorithm, an artificial immune system (AIS), for the data reduction process. We realized the performance evaluation experiments on the standard Chainlink and Iris datasets, while the main application …
Predics: A New Go-Po-Based Ray Launching Simulator For The Calculation Of Electromagnetic Scattering And Rcs From Electrically Large And Complex Structures, Caner Özdemi̇r, Betül Yilmaz, Özkan Kirik
Predics: A New Go-Po-Based Ray Launching Simulator For The Calculation Of Electromagnetic Scattering And Rcs From Electrically Large And Complex Structures, Caner Özdemi̇r, Betül Yilmaz, Özkan Kirik
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we present a new simulator called pRediCS for the calculation of electromagnetic scattering and radar cross-section (RCS) from electrically large and complex targets. The simulator utilizes the geometric optics (GO) theory and launching of electromagnetic rays for tracing and calculating the electric field values as the electromagnetic waves bounce around the target. The physical optics (PO) theory is also exploited to calculate the final scattered electric field by calculating the far-field PO integration along the observation direction. The simulator is first tested with known objects of canonical shapes, whose analytical solutions are available in the literature. Next, …
Sliding Mode Controller Design With Fractional Order Differentiation: Applications For Unstable Time Delay Systems, Celaleddi̇n Yeroğlu, Gürkan Kavuran
Sliding Mode Controller Design With Fractional Order Differentiation: Applications For Unstable Time Delay Systems, Celaleddi̇n Yeroğlu, Gürkan Kavuran
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a design method for a sliding mode controller with the contribution of a fractional order differential operator. The conventional sliding mode controller has been widely studied in different control applications. This paper proposes that the fractional order differential operator enlarges the output span of the classical sliding mode controller to obtain a better-fitting control signal for enhanced control performance. The sliding surface and the equivalent control law are modified with the addition of a fractional differential operator and a conventional one. The proposed sliding mode controller with fractional order differentiation is applied to the unstable time delay …
Abrupt And Incipient Fault Detection And Compensation For A 4-Tank System Benchmark, Pedram Hajiani, Javad Poshtan
Abrupt And Incipient Fault Detection And Compensation For A 4-Tank System Benchmark, Pedram Hajiani, Javad Poshtan
Turkish Journal of Electrical Engineering and Computer Sciences
Fault detection and compensation play a key role in enhancing the high demand for performance and security in technological systems. This paper proposes an active fault-tolerant control scheme that detects and compensates for actuator faults in a 4-tank system benchmark. The faults are modeled as a drastic gain loss in actuators (pumps), which could lead to a large loss in the nominal performance. The model-based approach uses a recursive least squares parameter estimation algorithm to form a fault detection and diagnosis subsystem and utilizes a parametric eigenstructure assignment method to reconfigure the state feedback controller. The designed controller is simulated …