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- Classification (66)
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Articles 1861 - 1890 of 3020
Full-Text Articles in Physical Sciences and Mathematics
Enhancement Of A Reduced Order Doubly Fed Induction Generator Model For Wind Farm Transient Stability Analyses, Mehmet Kenan Döşoğlu, Ayşen Basa Arsoy
Enhancement Of A Reduced Order Doubly Fed Induction Generator Model For Wind Farm Transient Stability Analyses, Mehmet Kenan Döşoğlu, Ayşen Basa Arsoy
Turkish Journal of Electrical Engineering and Computer Sciences
(DFIG) implemented for wind power systems is very important for transient stability. The rotor dynamic model (RDM) as well as the reduced order model (ROM) of a DFIG has been developed for transient analysis purpose. The performances of reduced order DFIG models with/without RDM have been compared. Modeling and analyses have been carried out in MATLAB/SIMULINK. Comparison of system behaviors against 3 phase fault is made between without RDM and with RDM. Several parameters such as output voltage, active power, speed, electrical torque variations, and d-q axis stator and rotor current variations of the DFIG along with a 34.5 kV …
Heuristic Methods For Postoutage Voltage Magnitude Calculations, Oğuzhan Ceylan, Aydoğan Özdemi̇r, Hasan Dağ
Heuristic Methods For Postoutage Voltage Magnitude Calculations, Oğuzhan Ceylan, Aydoğan Özdemi̇r, Hasan Dağ
Turkish Journal of Electrical Engineering and Computer Sciences
Power systems play a significant role in every aspect of our daily lives. Hence, their continuation without any interruption (or with the least duration of interruption due to faults or scheduled maintenances) is one of the key aims of electrical energy providers. As a result, electrical energy providers need to check in great detail the integrity of their power systems by performing regular contingency studies of the equipment involved. Among others, line and transformer outage simulations constitute an integral part of an electrical management system. Both accuracy and calculation speed depend on the branch outage model and/or the solution algorithms …
Behavior Learning Of A Memristor-Based Chaotic Circuit By Extreme Learning Machines, Ayşegül Uçar, Emrehan Yavşan
Behavior Learning Of A Memristor-Based Chaotic Circuit By Extreme Learning Machines, Ayşegül Uçar, Emrehan Yavşan
Turkish Journal of Electrical Engineering and Computer Sciences
As the behavior of a chaotic Chua's circuit is nonstationary and inherently noisy, it is regarded as one of the most challenging applications. One of the fundamental problems in the prediction of the behavior of a chaotic Chua's circuit is to model the circuit with high accuracy. The current paper presents a novel method based on multiple extreme learning machine (ELM) models to learn the chaotic behavior of the four elements canonical Chua's circuit containing a memristor instead of a nonlinear resistor only by using the state variables as the input. In the proposed method four ELM models are used …
Kernel Fisher Discriminant Analysis Of Gabor Features For Online Palmprint Verification, Murat Eki̇nci̇, Murat Aykut
Kernel Fisher Discriminant Analysis Of Gabor Features For Online Palmprint Verification, Murat Eki̇nci̇, Murat Aykut
Turkish Journal of Electrical Engineering and Computer Sciences
We propose an online palmprint identification and verification algorithm with the use of kernel Fisher discriminant analysis (KFD) on the Gabor wavelet representation of palm images. Desirable palm features are derived by Gabor wavelets on the palm region. The KFD method is then employed to extract higher order relations among the Gabor-palm images for palmprint recognition. As a real-world application, the proposed algorithm was adapted into a novel online palmprint verification system that was employed in a student laboratory for 3 months. The feasibility of the Gabor-based KFD method was successfully tested on our proposed online palmprint system and on …
Discriminant-Based Bistability Analysis Of A Tmg-Induced Lac Operon Model Supported With Boundedness And Local Stability Results, Nesli̇han Avcu, Güleser Kalayci Demi̇r, Ferhan Pekergi̇n, Hakan Alyürük, Levent Çavaş, Cüneyt Güzeli̇ş
Discriminant-Based Bistability Analysis Of A Tmg-Induced Lac Operon Model Supported With Boundedness And Local Stability Results, Nesli̇han Avcu, Güleser Kalayci Demi̇r, Ferhan Pekergi̇n, Hakan Alyürük, Levent Çavaş, Cüneyt Güzeli̇ş
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the results of a theoretical and numerical study on the analysis of bistable behavior of the most studied gene regulatory network, the lac operon, in terms of the model parameters. The boundedness of the state variables for the considered model are demonstrated, the parameter values providing the existence of the multiple equilibria and thus the bistable behavior are determined, and a local stability analysis of the equilibria is performed. The parameter region yielding the existence of multiple equilibria is determined in an algebraic way based on discriminants. The model given in the state equation form is defined …
An Application Of Simulated Annealing To Optimal Transcranial Direct Current Stimulation Of The Human Brain, Raheleh Tavakoli, Hamed Sadjedi, Seyyed Mohammad Pourmir Firoozabadi
An Application Of Simulated Annealing To Optimal Transcranial Direct Current Stimulation Of The Human Brain, Raheleh Tavakoli, Hamed Sadjedi, Seyyed Mohammad Pourmir Firoozabadi
Turkish Journal of Electrical Engineering and Computer Sciences
Transcranial direct current stimulation (tDCS) is known as the most effective technique for stimulating deeper brain areas. The capability of tDCS, however, strongly depends on the number of electrodes, their positions, and the amount of injected currents. This paper intends to apply the simulated annealing algorithm for determining optimal stimulation parameters in a multiple electrode scheme. The objective of the presented approach is to maximize the current density delivered to the target area under safety constraints. In order for the skin under the electrodes to be protected against temperature rises that may be caused by the stimulation, current injections are …
A Discrete Numerical Method For Magnetic Field Determination In Three-Phase Busbars Of A Rectangular Cross-Section, Tomasz Szczegielniak, Zygmunt Piatek, Bernard Baron, Pawel Jablonski, Dariusz Kusiak, Artur Pasierbek
A Discrete Numerical Method For Magnetic Field Determination In Three-Phase Busbars Of A Rectangular Cross-Section, Tomasz Szczegielniak, Zygmunt Piatek, Bernard Baron, Pawel Jablonski, Dariusz Kusiak, Artur Pasierbek
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a discrete numerical computation method for determining the magnetic field distributions in finite-length high-current bus ducts of rectangular busbars. This method is based on the integral equation method and the partial element equivalent circuit method. It takes into account the skin effect and proximity effects, as well as the complete electromagnetic coupling between phase bars and the neutral bar. In particular, the magnetic fields in busbars of unshielded three-phase systems with rectangular phase and neutral busbars and the use of the method are described. Finally, two applications to three-phase unshielded systems busbars are presented.
Modeling, Simulation, And Optimal Design Of Power System Stabilizers Using Abc Algorithm, Serdar Eki̇nci̇, Ayşen Demi̇rören
Modeling, Simulation, And Optimal Design Of Power System Stabilizers Using Abc Algorithm, Serdar Eki̇nci̇, Ayşen Demi̇rören
Turkish Journal of Electrical Engineering and Computer Sciences
This paper introduces a methodological system for modeling, simulation, and optimal tuning of the parameters of power system stabilizer (PSS) controllers in a multimachine power system so as to enhance transient stability. The model of a multimachine power system with PSS controllers is developed in MATLAB/Simulink for the simulation design. Simulink is a software instrument related to MATLAB, which is employed for modeling, simulating, and analyzing dynamical systems. The PSS controllers' design problem is expressed as an optimization problem; and the artificial bee colony (ABC) algorithm is utilized so as to examine the optimal PSS controller's parameters. The power system's …
Knowledge-Based Genetic Algorithm Approach To Quantization Table Generation For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan
Knowledge-Based Genetic Algorithm Approach To Quantization Table Generation For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan
Turkish Journal of Electrical Engineering and Computer Sciences
JPEG has played an important role in the image compression field for the past two decades. Quantization tables in the JPEG scheme is a key factor that is responsible for compression/quality trade-off. Finding the optimal quantization table is an open research problem. Studies recommend the genetic algorithm to generate the optimal solution. Recent reports revealed optimal quantization table generation based on a classical genetic algorithm (CGA). Although the CGA produces better results, it shows inefficiency in terms of convergence speed and productivity of feasible solutions. This paper proposes a knowledge-based genetic algorithm (KBGA), which combines the image characteristics and knowledge …
A New Algorithm For Detection Of Link Spam Contributed By Zero-Out Link Pages, Ravi Kumar Patchmuthu, Ashutosh Kumar Singh, Anand Mohan
A New Algorithm For Detection Of Link Spam Contributed By Zero-Out Link Pages, Ravi Kumar Patchmuthu, Ashutosh Kumar Singh, Anand Mohan
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Winding Temperature Prediction In Split-Winding Traction Transformer, Davood Azizian
Winding Temperature Prediction In Split-Winding Traction Transformer, Davood Azizian
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Design Of Low Power Cmos Lc Vco For Direct Conversion Transceiver, Manjula Sankararaju, Selvathi Dharmar
Design Of Low Power Cmos Lc Vco For Direct Conversion Transceiver, Manjula Sankararaju, Selvathi Dharmar
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Predicting Acute Hypotensive Episode By Using Hybrid Features And A Neuro-Fuzzy Network, Marzieh Abbasinia, Fardad Farokhi, Shahram Javadi
Predicting Acute Hypotensive Episode By Using Hybrid Features And A Neuro-Fuzzy Network, Marzieh Abbasinia, Fardad Farokhi, Shahram Javadi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents an approach for acute hypotensive episode (AHE) time series forecasting based on hybrid feature space and a neuro-fuzzy network. Prediction was accomplished through a combination of time domain and wavelet features by using six vital time series of each patient, obtained from MIMIC-II and available in the context of the Physionet-Computers in Cardiology 2009 Challenge. At first, statistical time domain features were used and then the wavelet coefficient was utilized for extracting time scale features. Further UTA feature selection was applied and 30 effective features were determined and achieved to predict AHE with 96.30 accuracy 1.5 h …
Design Of Low Power System On Programmable Chip For Video Zoom-In Processing, Lamjed Touil, Lilia Keciche, Bouraoui Ouni, Abdellatif Mtibaa
Design Of Low Power System On Programmable Chip For Video Zoom-In Processing, Lamjed Touil, Lilia Keciche, Bouraoui Ouni, Abdellatif Mtibaa
Turkish Journal of Electrical Engineering and Computer Sciences
Today, power consumption presents a critical issue when designing embedded systems. It has become a key factor in a product's success when being marketed, especially for mobile systems. In this paper, we have developed a typical design for video zoom-in processing with low power consumption. The proposed design has been implemented on the Xilinx Virtex-5 with the integration of different important resources like embedded processor, embedded memory, MPMC, DDR, and various interfaces. The design results show a significant gain in power at the simulation level as well as the physical one. In addition, the proposed design provides an important gain …
Pure Fuzzy Hall Effect Sensors For Permanent Magnet Synchronous Motor, İbrahi̇m Alişkan, Rüstem Yilmazel
Pure Fuzzy Hall Effect Sensors For Permanent Magnet Synchronous Motor, İbrahi̇m Alişkan, Rüstem Yilmazel
Turkish Journal of Electrical Engineering and Computer Sciences
An investigation about Hall effect sensors' efficiency is confirmed in permanent magnet synchronous motor (PMSM) drive systems. A fuzzy control algorithm is used as an artificial intelligence controller. Large scale and low slopes are used for creating membership functions and a sensitive controller is obtained. Speed is wanted to be taken under control and a minimum error value is aimed. PMSM drive systems are established using MATLAB-Simulink/SimPower. Simulations are realized with real-time parameters in discrete mode. A fuzzy logic controller is designed by using the MATLAB/Fuzzy Logic Toolbox. A normalization technique and high resolution output of the fuzzy logic controller …
Process Time And Mppt Performance Analysis Of Cf, Lut, And Ann Control Methods For A Pmsg-Based Wind Energy Generation System, Abdulhaki̇m Karakaya, Ercüment Karakaş
Process Time And Mppt Performance Analysis Of Cf, Lut, And Ann Control Methods For A Pmsg-Based Wind Energy Generation System, Abdulhaki̇m Karakaya, Ercüment Karakaş
Turkish Journal of Electrical Engineering and Computer Sciences
Due to environmental issues such as global warming and the greenhouse effect, there is a growing interest in renewable sources of energy. Wind energy, which is the most important of these energy sources, can potentially meet a portion of the global energy demand. Numerous studies are being conducted worldwide to determine how the maximum level of power can be obtained from wind energy. In these studies, there is a particular interest in permanent magnet synchronous generators (PMSGs). This is because PMSGs exhibit a good performance within a wide range wind speeds and can be driven directly. In this study, the …
A New Market-Based Approach For Daily Volt/Var Control Of Distribution Systems In The Presence Of Distributed Energy Resources Using Benders Decomposition Algorithm, Abouzar Samimi, Ahad Kazemi
A New Market-Based Approach For Daily Volt/Var Control Of Distribution Systems In The Presence Of Distributed Energy Resources Using Benders Decomposition Algorithm, Abouzar Samimi, Ahad Kazemi
Turkish Journal of Electrical Engineering and Computer Sciences
Distributed energy resources (DERs), if properly coordinated with other Volt/Var control (VVC) devices, could be incorporated in daily VVC problem. In this paper, a new 2-stage model is presented for daily VVC of distribution systems including DERs, taking into account environmental and economic aspects. First, in the day-ahead market, an initial environmental-economic dispatch is performed to minimize both the electrical energy costs and the gas emissions pertaining to generation units. The initial scheduling results determined by the market operator are delivered to the second stage, namely the daily optimal dispatches of VVC devices, to examine them from operational viewpoints and …
Fuzzy Speed Estimation In The Case Of Sensorless Induction Machine Vector Control, Mohamed Bahloul, Mansour Souissi, Mohamed Chaabane, Larbi Chrifi Alaoui, Said Drid
Fuzzy Speed Estimation In The Case Of Sensorless Induction Machine Vector Control, Mohamed Bahloul, Mansour Souissi, Mohamed Chaabane, Larbi Chrifi Alaoui, Said Drid
Turkish Journal of Electrical Engineering and Computer Sciences
This paper deals with the problem of sensorless indirect field oriented control of an induction machine. Based on the fourth-order nonlinear model, we propose a novel structure of a full-order Takagi-Sugeno (TS) adaptive observer, through which we ensure the estimation of IM states and the rotor speed, which is considered as an immeasurable premise variable. This approach satisfies global stability for all operating conditions and operates under unknown applied load torque. In this work, a TS fuzzy model is presented to approximate a nonlinear IM model in the stationary rotating reference frame. A TS adaptive observer is then described. We …
Development Of Derivation Of Inverse Jacobian Matrices For 195 6-Dof Gsp Mechanisms, Meti̇n Toz, Serdar Küçük
Development Of Derivation Of Inverse Jacobian Matrices For 195 6-Dof Gsp Mechanisms, Meti̇n Toz, Serdar Küçük
Turkish Journal of Electrical Engineering and Computer Sciences
One of the key issues in robotics is finding high-performance manipulator structures. To evaluate the performance of a parallel manipulator, researchers mostly use kinematic performance indices (such as condition number, minimum singular value, dexterity, and manipulability), which are based on inverse Jacobian matrices. Driving the inverse Jacobian matrix of even one parallel manipulator is a very cumbersome process. However, in this paper, general equations for the inverse Jacobian matrices of 195 GSP mechanisms are symbolically derived by considering 4 basic leg types having 1 angular and 4 distance constraints. With the help of these general equations, the development of the …
Stability Assessment Of Isolated Six-Phase Induction Generator Feeding Static Loads, Kiran Singh, Girish Kumar Singh
Stability Assessment Of Isolated Six-Phase Induction Generator Feeding Static Loads, Kiran Singh, Girish Kumar Singh
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the stability analysis of a six-phase self-excited induction generator (SP-SEIG) based on the eigenvalue stability criteria for its linearized model. This demonstrates the small signal stability behavior during steady-state operating conditions. The eigenvalue approach also establishes an opportunity to correlate eigenvalues with machine parameters. The investigation in this paper reveals that the eigenvalues are dependent upon the machine parameters, and the most critical parameter is the variation in magnetizing inductance (L$_{m})$. The eigenvalues are varied in accordance with the machine variables and give focus to the stabilization of the SP-SEIG. A particular voltage build-up phenomenon is also …
Experimental Performance Comparison Of A 2-Axis Sun Tracking System With Fixed System Under The Climatic Conditions Of Düzce, Turkey, Ali̇ Öztürk, Selman Alkan, Uğur Hasirci, Sali̇h Tosun
Experimental Performance Comparison Of A 2-Axis Sun Tracking System With Fixed System Under The Climatic Conditions Of Düzce, Turkey, Ali̇ Öztürk, Selman Alkan, Uğur Hasirci, Sali̇h Tosun
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, an experimental performance comparison of a 2-axis tracking system with a fixed panel in a solar renewable energy system is conducted. The paper mainly focuses on a cost-benefit analysis of fixed and tracking modules. For this aim, an experimental setup was built and periodical measurements were then obtained from the setup. To provide a better comparison, the panels were exposed to the same conditions during the measurements. By considering the real-time experimental results, the paper provides a quantitative analysis of the feasibility of tracking panels for domestic applications as well as an analysis of payback period if …
A New Dictionary-Based Preprocessor That Uses Radix-190 Numbering, Mete Eray Şenergi̇n, Erhan Ali̇ri̇za İnce
A New Dictionary-Based Preprocessor That Uses Radix-190 Numbering, Mete Eray Şenergi̇n, Erhan Ali̇ri̇za İnce
Turkish Journal of Electrical Engineering and Computer Sciences
Various scholarly works in the literature have pointed out that placing a preprocessor in front of a standard postcompressor would help achieve higher gains while compressing natural-language text files. Ever since, there has been much research on preprocessors to improve the gain attained by concatenated systems. With the same goal in mind our paper proposes a new word-based preprocessor named METEHAN190 (M190) and contrasts its performance with four other state-of-the-art preprocessors. Throughout the experiments source files from the Wall Street Journal (WSJ) archive, and the Calgary, Canterbury, Gutenberg, and Pizza and Chili corpora were used. Postcompressors adapted were Prediction by …
Novel Version Of Bi Input-Extended Kalman Filter For Speed-Sensorless Control Of Induction Motors With Estimations Of Rotor And Stator Resistances, Load Torque, And Inertia, Emrah Zerdali̇, Murat Barut
Novel Version Of Bi Input-Extended Kalman Filter For Speed-Sensorless Control Of Induction Motors With Estimations Of Rotor And Stator Resistances, Load Torque, And Inertia, Emrah Zerdali̇, Murat Barut
Turkish Journal of Electrical Engineering and Computer Sciences
This study aims to develop a novel version of bi input-extended Kalman filter (BI-EKF)-based estimation technique in order to increase the number of state and parameter estimations required for speed-sensorless direct vector control (DVC) systems, which perform velocity and position controls of induction motors (IMs). For this purpose, all states required for the speed-sensorless DVC systems, besides the stator resistance $R_{s} $, the rotor resistance $R_{r}$, the load torque $t_{L}$ including the viscous friction term, and the reciprocal of total inertia $1/j_{T}$, are simultaneously estimated by the novel BI-EKF algorithm using the measured phase currents and voltages. The effectiveness of …
A Problem Approximation Surrogate Model (Pasm) For Fitness Approximation In Optimizing The Quantization Table For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan
A Problem Approximation Surrogate Model (Pasm) For Fitness Approximation In Optimizing The Quantization Table For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan
Turkish Journal of Electrical Engineering and Computer Sciences
The quantization table in the baseline Joint Photographic Experts Group (JPEG) algorithm plays an important role in compression/quality trade-off. Hence the detection of the optimal quantization table is viewed as an optimization problem. The genetic algorithm (GA) is an attractive optimization tool by many researchers for this application due to its ability in dealing with complex problems. In spite of its advantages, the GA requires more computation time to achieve an optimal solution if it has an expensive fitness evaluation. This paper proposes a problem approximation surrogate model (PASM) for fitness approximation to assist the GA in optimizing the quantization …
Effect Of Transverse Magnetic Field On Low Pressure Argon Discharge, Ehsan Hashemi, Kaveh Niayesh, Hossein Mohseni
Effect Of Transverse Magnetic Field On Low Pressure Argon Discharge, Ehsan Hashemi, Kaveh Niayesh, Hossein Mohseni
Turkish Journal of Electrical Engineering and Computer Sciences
A numerical simulation was performed to investigate the effect of transverse magnetic fields on low pressure argon plasma. Discovering the variations in electric field, electric potential, power consumption in plasma, and dominant physical mechanisms after application of magnetic fields is the main output of this analysis. A simulation was performed using the finite element method. A 2-fluid model equipped with chemical reaction equations in argon plasma, heat transfer equation, and Poisson's equation was used to describe the plasma behavior. Two disk-shaped electrodes separated by 12 mm from each other were considered as a plasma chamber and an external transverse magnetic …
The Simulation Of Sound Signal Masking With Different Chaotic Oscillations And Its Circuit Application, Mehmet Nuri̇ Almali, Zi̇nnur Di̇ki̇ci̇
The Simulation Of Sound Signal Masking With Different Chaotic Oscillations And Its Circuit Application, Mehmet Nuri̇ Almali, Zi̇nnur Di̇ki̇ci̇
Turkish Journal of Electrical Engineering and Computer Sciences
The chaotic masking process on sound signals using the systems of Lorenz, Rössler, Sprott, Chen, and Arneodo chaotic oscillations are simulated with MATLAB/Simulink. The PID control method providing synchronization in the system is defined and the mean square errors between the times to reach synchronization and the input-output sound signals are compared for the system performance. The Sprott chaotic system is found to be the best synchronized system. Therefore, the application circuits are designed with respect to the Sprott chaotic system and its results are investigated in this study. It is seen that the system marked with the Sprott chaotic …
An Attribute Or Tuple Timestamping In Bitemporal Relational Databases, Canan Atay
An Attribute Or Tuple Timestamping In Bitemporal Relational Databases, Canan Atay
Turkish Journal of Electrical Engineering and Computer Sciences
Much of the research on bitemporal databases has focused on the modeling of time-related data with either attribute or tuple timestamping. While the attribute-timestamping approach attaches bitemporal data to attributes, the tuple-timestamping approach splits the object's history into several tuples. Although there have been numerous studies on bitemporal data models, there is no work contrasting these two common approaches in terms of system performance and ease of use. In this paper, we compared interval-based attribute- and tuple-timestamped bitemporal data models by running sample queries to measure processing time, and then we evaluated their usability by using the same data. Our …
Iec 61850-Based Parallel Bus Transfer Scheme For Industrial Substations, Cagil Ozansoy
Iec 61850-Based Parallel Bus Transfer Scheme For Industrial Substations, Cagil Ozansoy
Turkish Journal of Electrical Engineering and Computer Sciences
Bus transfer schemes have long been utilized in the power system industry as a means of supplying system loads with a consistent and reliable source of power. They assist in the switch to alternative sources of power supply in the case of maintenance or failures. The design of such schemes has undergone significant transformation from discrete electromechanical relays to microprocessor-based relays with sophisticated communication capabilities. IEC 61850 is a substation automation standard for the communication between devices in a substation. IEC 61850 makes it possible to integrate intelligent electronic devices on an Ethernet-based peer-to-peer communication network, eliminating the traditional hardwiring …
A New Compression Algorithm For Fast Text Search, Aydin Carus, Altan Mesut
A New Compression Algorithm For Fast Text Search, Aydin Carus, Altan Mesut
Turkish Journal of Electrical Engineering and Computer Sciences
We propose a new compression algorithm that compresses plain texts by using a dictionary-based model and a compressed string-matching approach that can be used with the compressed texts produced by this algorithm. The compression algorithm (CAFTS) can reduce the size of the texts to approximately 41% of their original sizes. The presented compressed string matching approach (SoCAFTS), which can be used with any of the known pattern matching algorithms, is compared with a powerful compressed string matching algorithm (ETDC) and a compressed string-matching tool (Lzgrep). Although the search speed of ETDC is very good in short patterns, it can only …
Digital Implementation Of A Constant Frequency Hysteresis Controller For Dual Mode Operation Of An Inverter Acting As A Pv-Grid Interface And Statcom, Lenin Prakash, Arutchelvi Meenakshi Sundaram, Kalyanraj Durairaj
Digital Implementation Of A Constant Frequency Hysteresis Controller For Dual Mode Operation Of An Inverter Acting As A Pv-Grid Interface And Statcom, Lenin Prakash, Arutchelvi Meenakshi Sundaram, Kalyanraj Durairaj
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a new constant frequency hysteresis current controller for the grid interface of a PV-fed three-phase voltage source inverter (VSI) for a dual mode operation, feeding real power during the daytime and reactive power alone during nights, thereby acting as a STATCOM. The constant frequency is inherently achieved by means of digital implementation in a simplified manner without any complex manipulations to choose a variable band width; rather the hysteresis band varies as a natural consequence of selecting appropriate constant sampling frequency. Analytical proof is presented for the switching frequency to remain constant, without compromising on the performance …