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Articles 2071 - 2100 of 3020
Full-Text Articles in Physical Sciences and Mathematics
Computer Vision-Based Control Of An Autonomous Blimp, Korkut Beki̇roğlu, Mario Sznaier, Constantino Lagoa, Bahram Shafai
Computer Vision-Based Control Of An Autonomous Blimp, Korkut Beki̇roğlu, Mario Sznaier, Constantino Lagoa, Bahram Shafai
Turkish Journal of Electrical Engineering and Computer Sciences
The objective of this study is twofold: to approximate a model of a blimp, and to use this model to develop a setup to track a target with the blimp that is outfitted with a wireless camera and radio-controlled propellers. This article presents a powerful method to track any moving or stationary target with an unmanned aerial vehicle by combining the advantages of the proportional derivative (PD) controller, continuously adaptive mean shift (Camshift) algorithm, and pulse width modulation (PWM) method. As a result, it is demonstrated that a decent approximation of blimp behavior is sufficient when using a mathematical model …
Vector Control Of A Three-Phase Parallel Connected Two Motor Single Inverter Speed Sensorless Drive, Gunabalan Ramachandran, Subbiah Veerana, Sanjeevikumar Padmanaban
Vector Control Of A Three-Phase Parallel Connected Two Motor Single Inverter Speed Sensorless Drive, Gunabalan Ramachandran, Subbiah Veerana, Sanjeevikumar Padmanaban
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the performance characteristics of two induction motors of the same parameters and ratings connected in parallel and fed by a single inverter. A nature observer is employed to estimate the rotor speeds and rotor fluxes of both induction motors. It also estimates the load torques of both the motors by load torque adaptation. Under unbalanced load conditions, the speed difference between the two induction motors is reduced by considering the average and differential motor parameters and currents. Mean rotor flux is maintained constant by a rotor flux control scheme and the estimation of rotor angle is carried …
Fuzzy Based Design Of Digital Iir Filter Using Etlbo, Damanpreet Singh, Jaspreet Singh Dhillon
Fuzzy Based Design Of Digital Iir Filter Using Etlbo, Damanpreet Singh, Jaspreet Singh Dhillon
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a population-based robust enhanced teaching--learning-based optimization (ETLBO) algorithm with reduced computational effort and high consistency is applied to design stable digital infinite-impulse response (IIR) filters in a multiobjective framework. Furthermore, a decision-making methodology based on fuzzy set theory is applied to handle nonlinear and multimodal design problems of the IIR digital filter. The original teaching--learning-based optimization (TLBO) algorithm has been remodeled by merging the concepts of opposition-based learning and migration for the selection of good candidates and to maintain diversity, respectively. A multiobjective IIR digital filter design problem takes into consideration magnitude and phase response of the …
Determination Of The Striking Distance Of A Lightning Rod Using Finite Element Analysis, Ab Halim Abu Bakar, Alyaa Zainal Abidin, Hazlee Illias, Hazlie Mokhlis, Syahirah Abd Halim, Nor Hidayah Nor Hassan, Chia Kwang Tan
Determination Of The Striking Distance Of A Lightning Rod Using Finite Element Analysis, Ab Halim Abu Bakar, Alyaa Zainal Abidin, Hazlee Illias, Hazlie Mokhlis, Syahirah Abd Halim, Nor Hidayah Nor Hassan, Chia Kwang Tan
Turkish Journal of Electrical Engineering and Computer Sciences
The problems related to electromagnetic waves transmitted by lightning strikes can be studied through physical lightning models based on laboratory results. The main concern of these models is determining the striking distance between the leader tip and the lightning rod during lightning occurrences. The striking distance is a significant factor in designing the lightning protection system. However, models using finite element analysis (FEA) for this purpose are less likely to be found in the literature. Therefore, in this work, a geometry model of a lightning rod and leader was developed using available FEA software. The model was used to determine …
Performance Comparison Of Adaptive Digital Predistortion Algorithms Using Adaptation Time For Mobile Wimax Power Amplifier Applications, Ji-Yeon Kim, Jong-Heon Kim
Performance Comparison Of Adaptive Digital Predistortion Algorithms Using Adaptation Time For Mobile Wimax Power Amplifier Applications, Ji-Yeon Kim, Jong-Heon Kim
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we propose that adaptation time be considered a parameter for evaluating the performance of digital filter algorithms in adaptive digital predistorted high-power amplifiers. An adaptive predistorted high-power amplifier with an average power of 37.5 dBm was designed and fabricated for mobile worldwide interoperability for microwave access (WiMAX) test signals. For performance comparisons using adaptation time, several effective algorithms (such as the least-mean-squares (LMS), recursive-least-squares (RLS), and affine projection (AP) algorithms) were implemented. According to the experimental results, the RLS and AP algorithms achieved a similar linearity improvement of 11 dBr. However, the AP algorithm had the advantage …
Energy-Aware Stochastic Scheduling Model With Precedence Constraints On Dvfs-Enabled Processors, Mohammad Sajid, Zahid Raza
Energy-Aware Stochastic Scheduling Model With Precedence Constraints On Dvfs-Enabled Processors, Mohammad Sajid, Zahid Raza
Turkish Journal of Electrical Engineering and Computer Sciences
The stochastic scheduling of precedence-constrained jobs on a heterogeneous processor is a challenging problem that requires solutions with one or more optimized QoS parameters. In this work, an energy-aware stochastic algorithm is proposed to schedule the batch of precedence-constrained jobs on heterogeneous DVFS-enabled processors with the objective of optimizing turnaround time and energy consumption. The processing time of tasks in all jobs and their precedence-constraint times are governed by independent probability distributions. The performance of the proposed stochastic algorithm is compared with SHEFT and ECS based on randomly generated batches of different sizes. The experimental study reveals that the proposed …
Assessment Of The Maximum Loadability Point Of A Power System After Third Zone Of Distance Relay Corrective Actions, Zahra Moravej, Sajad Bagheri
Assessment Of The Maximum Loadability Point Of A Power System After Third Zone Of Distance Relay Corrective Actions, Zahra Moravej, Sajad Bagheri
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, the operation of a system and distance relay is improved during voltage instability by using an improved strategy. After detecting the voltage instability, the third zone is blocked. However, the system is prone to voltage collapse. Shunt capacitor compensation and a load shedding scheme can be used to protect the system from voltage collapse conditions. Load shedding plans can be performed based on a reduction in the power flow in the line where the relay is located. The reason is that the minimum eigenvalue of the load flow Jacobian (reduced and unreduced Jacobians) is increased and the …
Evaluation Of Hearing Loss Simulation Using A Speech Intelligibility Index, Umut Ariöz, Banu Günel
Evaluation Of Hearing Loss Simulation Using A Speech Intelligibility Index, Umut Ariöz, Banu Günel
Turkish Journal of Electrical Engineering and Computer Sciences
Hearing loss simulation (HLS) is a useful tool for hearing studies, since finding large numbers of hearing-impaired volunteers with various levels of hearing loss is usually a problem. Correct simulation of the hearing impaired ear should take into account different suprathreshold effects, such as reduced frequency selectivity, reduced audibility, and loudness recruitment. Although these effects can be implemented using various algorithms, so far they have not been evaluated in detail taking into account subject dependency, effect of noisy environment, and phonetic characteristics of test words. In this study, for the purpose of evaluating the HLS, a speech intelligibility index (SII) …
High Photoresponse From Solution Processed Conventional And Inverted Ultraviolet Photodetectors, Görkem Memi̇şoğlu, Canan Varlikli
High Photoresponse From Solution Processed Conventional And Inverted Ultraviolet Photodetectors, Görkem Memi̇şoğlu, Canan Varlikli
Turkish Journal of Electrical Engineering and Computer Sciences
The optical and electrical properties of conventional and inverted type ultraviolet photodetectors (UVPDs) with active layers of poly(9,9-dioctylfluorenyl-2,7-ylenethynylene (PFE), $N$,$N'$-bis-$n$-butyl-1,4,5,8-naphthalenediimide (BNDI), and zincoxide (ZnO) are introduced. Optimized devices showed high photoresponse, external quantum efficiency (EQE), and detectivity (D*) values. Under 365 nm 1 mW/cm$^{2}$, the conventional device (ITO/PEDOT:PSS/[(PFE:BNDI) (3:1):8 wt% ZnO]/Al) and the inverted device (ITO/[(PFE:BNDI)(3:1):8 wt% ZnO]/Au) gave photoresponsivities of 515 mA/W and 316 mA/W, D* of 1.12 $\times$ 10$^{14 }$Jones and 0.71 $\times$ 10$^{14 }$Jones, and EQE of 174% and 107%, respectively. Annealing the devices at polymer's glass transition temperature (T$_{g}$ 60 $^{\circ}$ C), enhanced these values to …
A Generalized Algorithm For Space Vector Modulation In Multilevel Inverters, Erkan Meşe
A Generalized Algorithm For Space Vector Modulation In Multilevel Inverters, Erkan Meşe
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a new space vector pulse width modulation (SVPWM) algorithm for multilevel inverters that achieves a minimum number of switch state changes in one sampling cycle in order to reduce switching losses. The algorithm can be implemented with minimum computational burden and it does not require any look-up tables. The essence of the technique is to exploit the redundancy of switching functions in the implementation of the voltage vectors and dividing the entire vector space into three sectors in which switching functions have some common features. Careful observations showed that these common features lend themselves to be expressed …
A Novel Voltage Control Strategy In Collaboration With Information Technology Domains Through The Holonic Architecture, Javad Ansari, Mehdi Ghazavi Dozein, Ahad Kazemi
A Novel Voltage Control Strategy In Collaboration With Information Technology Domains Through The Holonic Architecture, Javad Ansari, Mehdi Ghazavi Dozein, Ahad Kazemi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a novel framework for voltage control based on holonic architecture, with a priority action of local controllers. The proposed architecture is a hierarchical distributed structure in which two various information technology domains called the energy management system holon and flexible AC transmission system holon are defined. In the proposed structure, a dynamic reconfiguring method for holons is used to reduce the time of corrective actions in the case of emergencies.
Keyframe-Based Video Mosaicing For Historical Ottoman Documents, Edi̇z Şaykol
Keyframe-Based Video Mosaicing For Historical Ottoman Documents, Edi̇z Şaykol
Turkish Journal of Electrical Engineering and Computer Sciences
Image mosaicing is a trendy research area in computer vision in recent years. Instead of images, video frames can be mosaiced to form a larger aggregate. In both cases, merging computations generally depend on the common parts in consecutive images, which are called overlapping regions. The presence of mobile devices with a camera provides higher image and video acquisition; hence video mosaicing techniques can be utilized to digitize and to create high resolution historical document images for later use in browsing and retrieval systems. Here, we present a technique to create high resolution images of historical Ottoman documents from video. …
Enhancing Sliding Mode Control With Proportional Feedback And Feedforward: An Experimental Investigation On Speed Sensorless Control Of Pm Dc Motor Drives, Mehmet Dal
Turkish Journal of Electrical Engineering and Computer Sciences
This paper investigates the enhancement of sliding mode control (SMC) with the combined use of feedforward torque compensation and proportional error feedback control. The proposed enhancement is adapted to the control of permanent magnet (PM) DC motor drives by synthesis of the equivalent control equation augmented as proportional feedback and feedforward terms. A novel sliding function, introduced by utilizing the estimated load torque and the estimated rotor current, is examined and compared with another known sliding function obtained by nonideal differentiation of the estimated rotor speed. The significance of the proposed enhancements to SMC consists of the elimination of disturbance, …
Investigation Of Respiratory And Heart Rate Variability In Hypertensive Patients, Ramazan Aldemi̇r, Mahmut Tokmakçi
Investigation Of Respiratory And Heart Rate Variability In Hypertensive Patients, Ramazan Aldemi̇r, Mahmut Tokmakçi
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, in order to examine the effect of respiration on heart rate variability (HRV), signal processing analyses were performed between the signal received from the periodic movement of the chest of respiration and the pulse plethysmograph (PPS) signal, providing the calculation of both the time and frequency behavior of HRV and also including pulse rate information at the same time. Respiration is used as the comparison parameter in both healthy subjects and in hypertensive patients, not only with the time and frequency components of the HRV, but also with the galvanic skin resistance simultaneously taken with body temperature …
A Hierarchic Approach Based On Swarm Intelligence To Solve The Traveling Salesman Problem, Mesut Gündüz, Mustafa Servet Kiran, Eren Özceylan
A Hierarchic Approach Based On Swarm Intelligence To Solve The Traveling Salesman Problem, Mesut Gündüz, Mustafa Servet Kiran, Eren Özceylan
Turkish Journal of Electrical Engineering and Computer Sciences
The purpose of this paper is to present a new hierarchic method based on swarm intelligence algorithms for solving the well-known traveling salesman problem. The swarm intelligence algorithms implemented in this study are divided into 2 types: path construction-based and path improvement-based methods. The path construction-based method (ant colony optimization (ACO)) produces good solutions but takes more time to achieve a good solution, while the path improvement-based technique (artificial bee colony (ABC)) quickly produces results but does not achieve a good solution in a reasonable time. Therefore, a new hierarchic method, which consists of both ACO and ABC, is proposed …
Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan
Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan
Turkish Journal of Electrical Engineering and Computer Sciences
The problem of discrete-time modeling of the lumped-parameter Hamiltonian systems is considered for engineering applications. Hence, a novel gradient-based method is presented, exploiting the discrete gradient concept and the forward Euler discretization under the assumption of the continuous Hamiltonian model is known. It is proven that the proposed discrete-time model structure defines a symplectic difference system and has the energy-conserving property under some conditions. In order to provide alternate discrete-time models, 3 different discrete-gradient definitions are given. The proposed models are convenient for the design of sampled-data controllers. All of the models are considered for several well-known Hamiltonian systems and …
Mras-Based Sensorless Speed Backstepping Control For Induction Machine, Using A Flux Sliding Mode Observer, Mohamed Moutchou, Ahmed Abbou, Hassan Mahmoudi
Mras-Based Sensorless Speed Backstepping Control For Induction Machine, Using A Flux Sliding Mode Observer, Mohamed Moutchou, Ahmed Abbou, Hassan Mahmoudi
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, an induction machine rotor speed and rotor flux control using a sensorless backstepping control scheme is discussed. The most interesting point of this technique is that it deals with the nonlinearity of a high-order system by using the virtual control variable to make this system simple, and thus the control outputs can be derived step by step through appropriate Lyapunov functions. To avoid the use of a mechanical sensor, the rotor speed estimation is made by an observer using the model reference adaptive system (MRAS) technique; in order to estimate rotor flux, a sliding mode observer is …
Short-Term Load Forecasting Without Meteorological Data Using Ai-Based Structures, İdi̇l Işikli Esener, Tolga Yüksel, Mehmet Kurban
Short-Term Load Forecasting Without Meteorological Data Using Ai-Based Structures, İdi̇l Işikli Esener, Tolga Yüksel, Mehmet Kurban
Turkish Journal of Electrical Engineering and Computer Sciences
STLF is used in making decisions about economical power generation capacity, fuel purchasing, safety assessment, and power system planning in order to have economical power conditions. In this study, Turkey's 24-hour-ahead load forecasting without meteorological data is studied. ANN, wavelet transform and ANN, wavelet transform and RBF NN, and EMD and RBF NN structures are used in STLF procedures. Local holidays' historical load data are changed into data with normal day characteristics, and the estimation results of these days are not included in error computation. To obtain more accurate results, a regulation on forecasted loads is proposed. Regulated and unregulated …
An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz
An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new method based on artificial neural network (ANN) and discrete wavelet transform (DWT) is proposed for electrical islanding detection. Transient signals produced during an event are used in the proposed method. ANN is trained to classify the transient events as islanding and nonislanding. The required features for classifying are extracted through DWT of voltage and current transient signals. The proposed method is then simulated on a medium voltage distribution system of CIGRE with 2 kinds of DGs. Results show that this method can detect electrical islands more rapidly and accurately.
Continuous-Time Hopfield Neural Network-Based Optimized Solution To 2-Channel Allocation Problem, Zekeri̇ya Uykan
Continuous-Time Hopfield Neural Network-Based Optimized Solution To 2-Channel Allocation Problem, Zekeri̇ya Uykan
Turkish Journal of Electrical Engineering and Computer Sciences
The channel allocation problem in cellular radio systems is NP-complete, and thus its general solution is not known for even the 2-channel case. It is well known that the link gain system matrix (or received-signal power system matrix) of the radio network is (and may be highly) asymmetric, and that as the Hopfield neural network is applied to optimization problems, its weight matrix should be symmetric. The main contribution of this paper is as follows: turning the channel allocation problem into a maxCut graph partitioning problem, we propose a simple and effective continuous-time Hopfield neural network-based solution by determining its …
Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani
Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani
Turkish Journal of Electrical Engineering and Computer Sciences
In recent years, there have been significant advances in communication technology, but speech signals still suffer from low perceived quality caused by bandwidth limitations of telephone networks. The bandwidth extension (BWE) approach adds high-frequency components of the speech signal to band-limited telephone speech and increases speech perception significantly. In this work, we develop a new method for representation of vocal tract filter coefficients using log of filter bank energy (LFBE) parameters as an alternative for mel-frequency cepstral coefficients (MFCCs). This approach is based on a strong correlation between the spectral components of low- and high-band spectrums. Furthermore, the performances of …
Model-Based Test Case Prioritization Using Cluster Analysis: A Soft-Computing Approach, Ni̇da Gökçe, Fevzi̇ Belli̇, Mübari̇z Emi̇nli̇, Beki̇r Taner Di̇nçer
Model-Based Test Case Prioritization Using Cluster Analysis: A Soft-Computing Approach, Ni̇da Gökçe, Fevzi̇ Belli̇, Mübari̇z Emi̇nli̇, Beki̇r Taner Di̇nçer
Turkish Journal of Electrical Engineering and Computer Sciences
Model-based testing is related to the particular relevant features of the software under test (SUT) and its environment. Real-life systems often require a large number of tests, which cannot exhaustively be run due to time and cost constraints. Thus, it is necessary to prioritize the test cases in accordance with their importance as the tester perceives it, usually given by several attributes of relevant events entailed. Based on event-oriented graph models, this paper proposes an approach to ranking test cases in accordance with their preference degrees. For forming preference groups, events are clustered using an unsupervised neural network and fuzzy …
Detection Of Microcalcification In Digitized Mammograms With Multistable Cellular Neural Networks Using A New Image Enhancement Method: Automated Lesion Intensity Enhancer (Alie), Levent Ci̇vci̇k, Burak Yilmaz, Yüksel Özbay, Gani̇me Di̇lek Emli̇k
Detection Of Microcalcification In Digitized Mammograms With Multistable Cellular Neural Networks Using A New Image Enhancement Method: Automated Lesion Intensity Enhancer (Alie), Levent Ci̇vci̇k, Burak Yilmaz, Yüksel Özbay, Gani̇me Di̇lek Emli̇k
Turkish Journal of Electrical Engineering and Computer Sciences
Microcalcification detection is a very important issue in early diagnosis of breast cancer. Generally physicians use mammogram images for this task; however, sometimes analyzing these images become a hard task because of problems in images such as high brightness values, dense tissues, noise, and insufficient contrast level. In this paper, we present a novel technique for the task of microcalcification detection. This technique consists of three steps. The first step is focused on removing pectoral muscle and unnecessary parts from the mammogram images by using cellular neural networks (CNNs), which makes this a novel process. In the second step, we …
A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors, Nuretti̇n Üstkoyuncu, Krishnan Ramu
A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors, Nuretti̇n Üstkoyuncu, Krishnan Ramu
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a comprehensive comparison between conventional (longitudinal flux) linear switched reluctance machines (CLSRMs) and transverse flux linear switched reluctance machines (TLSRMs) so as to enable engineers to choose a structure suitable for their applications. A commonly-used single-sided CLSRM and 4 different TLSRM structures are considered for the comparison. For a fair comparison of the 2 types of LSRMs, equal dimensions, including equal length and magnetomotive force, are applied as much as possible. The analytical approach and 3-dimensional finite element analysis (FEA) are employed to obtain the performance of these machines. It is proven analytically that the CLSRM has …
Load Management In A Distributed Multimedia Streaming Environment Using A Fault-Tolerant Hierarchical System, Hadi̇ Işik Aybay, Mohammad Ahmed Shah
Load Management In A Distributed Multimedia Streaming Environment Using A Fault-Tolerant Hierarchical System, Hadi̇ Işik Aybay, Mohammad Ahmed Shah
Turkish Journal of Electrical Engineering and Computer Sciences
In contrast to text-only forms of communications, multimedia uses a combination of audiovisual means alongside textual modes of communication. Streaming multimedia is such multimedia that is constantly delivered by a provider of the multimedia to a client. In streaming multimedia the streamed content is continually presented to and received by the end user. Distributed multimedia systems (DMSs) deliver multimedia content to end-users by means of distributed multimedia databases and distributed information servers. These DMSs are designed to deliver multimedia content over a network. A fault-tolerant redundant hierarchy (Red-HI)-based load management policy for a distributed multimedia streaming system is proposed in …
Amorphous Core Transformers Efficiency Analysis In Turkish Electrical Distribution Systems, Fati̇h Işik, Yilmaz Uyaroğlu
Amorphous Core Transformers Efficiency Analysis In Turkish Electrical Distribution Systems, Fati̇h Işik, Yilmaz Uyaroğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Transformers are an indispensable element in the transmission and distribution of electricity. While they are highly efficient, the increasing global demand for electrical energy has prompted efforts to improve their performance. No-load power losses constitute the majority of total losses within electrical energy distribution, especially when looking at load ratio. In recent years, some studies have found that no-load power losses of amorphous core transformers are less than those of laminated steel core transformers by as much as 60{\%} to 70{\%}. For this paper, we have manufactured an amorphous distribution transformer prototype rated 33 kV and 1 MVA. By quantifying …
Active Filter Solutions In Energy Systems, Sabi̇r Rüstemli̇, Mehmet Sai̇t Cengi̇z
Active Filter Solutions In Energy Systems, Sabi̇r Rüstemli̇, Mehmet Sai̇t Cengi̇z
Turkish Journal of Electrical Engineering and Computer Sciences
Recent developments in power electronics have increased the usage of nonlinear loads in energy systems. With increases in the usage of semiconductor-sourced nonlinear loads, the adverse effects of harmonics-sensitive loads (e.g., protection control circuits and circuit breakers) have also increased. Generally, the negative effects of harmonics in power systems include the following: increased power losses; motor, generator, and transformer overheating; faulty operation of measurement and protection systems; lifetime shortening of electrical components; and parallel and series resonance problems. Therefore, harmonics has become a serious problem in current power electronics systems. However, harmonics can be reduced, particularly through drainage using filters. …
Variable Charge/Discharge Time-Interval Control Strategy Of Bess For Wind Power Dispatch, Wei Chai, Zheng Li, Xu Cai
Variable Charge/Discharge Time-Interval Control Strategy Of Bess For Wind Power Dispatch, Wei Chai, Zheng Li, Xu Cai
Turkish Journal of Electrical Engineering and Computer Sciences
A variable charge/discharge time-interval ($T_{C/D})$ control strategy of a battery energy storage system (BESS) for wind power dispatch is proposed in this paper, aiming at: 1) extending the BESS life, 2) reducing the total BESS energy loss, and 3) increasing the dispatch tracking accuracy. A multifactor life model of a large-scale BESS containing four factors, charge/discharge rate, times, $T_{C/D}$, and temperature, is developed, which has taken into account the cell series/parallel effects and BESS operational characteristics. A comprehensive evaluation system including BESS aging level (BAL), energy loss index (ELI), and tracking inaccuracy index (TII) is proposed, and the relationships between …
Performance Evaluation Of Three Phase Srf-Pll And Maf-Srf-Pll, Anirban Ghoshal, Vinod John
Performance Evaluation Of Three Phase Srf-Pll And Maf-Srf-Pll, Anirban Ghoshal, Vinod John
Turkish Journal of Electrical Engineering and Computer Sciences
Synchronous reference frame phase locked loop (SRF-PLL) is a well established technique used for maintaining synchronism of a grid connected VSI with an electric grid. Many methods of PLL are present in the literature to achieve improved performance under nonideal grid condition. These solutions are based on SRF-PLL structure along with some modification to achieve improved performance. It is observed that faster and better performance are achieved at the expense of more computations. Moving average filter (MAF) SRF-PLL structure is one such solution that consumes less resources and gives a reasonably fast response. In this work the performance of a …
Capacity Allocation Of Hybrid Solar-Wind Energy System Based On Discrete Probabilistic Method, Chengjin Ye, Minxiang Huang
Capacity Allocation Of Hybrid Solar-Wind Energy System Based On Discrete Probabilistic Method, Chengjin Ye, Minxiang Huang
Turkish Journal of Electrical Engineering and Computer Sciences
Complementary renewable energies like wind and solar power may be more sufficient to satisfy reliability requirements. This paper proposes a quantitative capacity allocation method of a hybrid wind and solar energy system. First, discrete probability distributions are established to model the random factors including the volatility of power outputs and the failure of components. Then a multiobjective optimization model is formulated with objectives of minimization of the total investment, the nodal voltages violating limits probability, and power supply inadequacy probability. For the purpose of fast probability computing with a satisfactory precision degree, an innovative probabilistic load flow algorithm is introduced, …