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Öğe A Fast Simulation Model for Large Scale Battery Packs Used in Heavy Electric Vehicles(Institute of Electrical and Electronics Engineers Inc., 2019) Erdogan, Birand; Savrun, Murat Mustafa; Koroglu, Tahsin; Cuma, Mehmet Ugras; Tumay, MehmetVoltage imbalance occurs in a battery pack due to the differences of internal resistance, temperature, self discharge rate, leakage current etc. reduce the usable energy over time. To overcome voltage imbalances in the battery pack, cell balancing methodologies are used. Although passive balancing methods provide cheap solutions for equalizing imbalances, active balancing methods make it possible to balance faster. This paper presents an active balancing topology for large scale battery packs in a heavy electric vehicle. In order to investigate the performance of the system, a battery pack and bidirectional flyback converter (BiFLC) based active balancing circuit equipped with switch matrix (SwM) has been simulated by using MATLAB/Simulink. A charge transfer bus, which is supplied by the first cell of the battery pack, is used to transfer energy between the source/ destination cells. Thus, the need for the auxiliary circuit/battery is eliminated. A large scale battery pack consist of 176 series cells and 22 BiFLCs is used in the simulation model. Because of using switching models of BiFLCs requires high run time and more complexity, a simple model of BiFLC using current sources is presented. © 2019 IEEE.Öğe A Fuzzy Neural Network Approach to Estimate PMSG based and DFIG based Wind Turbines' Power Generation(IEEE, 2017) Demirdelen, Tugce; Bakmaz, Emel; Tumay, MehmetNeural networks and fuzzy systems are amalgamate their advantages and to eliminate its individual disadvantages. Neural networks have its computational characteristics of learning in the fuzzy systems and receive from them the interpretation and clarity of systems representation. Thus, the disadvantages of the fuzzy systems are fulfilled by the capacities of the neural networks. These techniques are complementary, which prove its use together. This is called fuzzy neural networks In this paper, a fuzzy neural network is applied to estimate PMSG based and DFIG based wind turbines' power generation. The obtained results showed that this model can be used to predict wind turbine power generation and performance analysis both two type turbines in a simple, reliable and accurate way.Öğe A fuzzy neural network approach to estimate PMSG based and DFIG based wind turbines' power generation(Institute of Electrical and Electronics Engineers Inc., 2017) Demirdelen, Tu?çe; Bakmaz, Emel; Tumay, MehmetNeural networks and fuzzy systems are amalgamate their advantages and to eliminate its individual disadvantages. Neural networks have its computational characteristics of learning in the fuzzy systems and receive from them the interpretation and clarity of systems representation. Thus, the disadvantages of the fuzzy systems are fulfilled by the capacities of the neural networks. These techniques are complementary, which prove its use together. This is called fuzzy neural networks In this paper, a fuzzy neural network is applied to estimate PMSG based and DFIG based wind turbines' power generation. The obtained results showed that this model can be used to predict wind turbine power generation and performance analysis both two type turbines in a simple, reliable and accurate way. © 2017 IEEE.Öğe A review of magnetically controlled shunt reactor for power quality improvement with renewable energy applications(Pergamon-Elsevier Science Ltd, 2017) Tumay, Mehmet; Demirdelen, Tugce; Bal, Selva; Kayaalp, Rahmi Ilker; Dogru, Burcu; Aksoy, MahmutRenewable energy sources are widely available on Earth; hence they have attracted much interest in both research and practical applications. In the large scale renewable energy system, power quality into the grid, especially harmonics and flicker, impacts on grid system significantly. In recent years, magnetically controlled shunt reactors (MCSRs) have been widely used to solve the problems of the power quality caused a failure or malfunction of the end-user equipment. MCSR can simplify the system reactive power and voltage control in the super / special high-voltage power grid, suppress power frequency and operation over voltage, eliminating generator self excitation, dynamically compensate charging the power in a transmission line, suppress the secondary arc current, damping system resonance and so on, which can meet the various needs of the system, it has a very broad application prospects. This paper presents a comprehensive review of MCSR configurations, the control strategies, the selection of components, other related economic and technical considerations, and their selection for specific applications. It is aimed at providing a broad perspective on the status of MCSR technology to the researchers and the application engineers dealing with power quality issues. A list of more than 130 research publications on the subject is also appended for a quick reference.Öğe An improved and fast balancing algorithm for electric heavy commercial vehicles(Elsevier, 2021) Erdogan, Birand; Savrun, Murat Mustafa; Koroglu, Tahsin; Cuma, Mehmet Ugras; Tumay, MehmetNowadays, the tendency towards electric vehicles is increasing and various studies are being carried out in order to eliminate the shortage of battery life. One way to improve battery life is to overcome imbalances between cells in battery packs. The imbalances due to structural differences arising from production and changing operating conditions reduce the utilization of available energy. Passive and active balancing methods are used in order to eliminate these imbalances. Due to the slow equalization speed and energy inefficiency of passive balancing circuits, the trend towards active balancing is increasing. In this paper, an active balancing system with a new balancing algorithm that features fast balancing, multiple charge transfers, and suitable for large battery packs used in electric heavy commercial vehicles is proposed to increase usable energy. To test the algorithm, battery module and bidirectional dc-dc converter based active balancing system simulation study has been performed in Matlab-Simulink. The performance of proposed algorithm is compared with other algorithms and simulation results show that the proposed algorithm has better balancing performance.Öğe An improved and fast balancing algorithm for electric heavy commercial vehicles(Elsevier, 2021) Erdogan, Birand; Savrun, Murat Mustafa; Koroglu, Tahsin; Cuma, Mehmet Ugras; Tumay, MehmetNowadays, the tendency towards electric vehicles is increasing and various studies are being carried out in order to eliminate the shortage of battery life. One way to improve battery life is to overcome imbalances between cells in battery packs. The imbalances due to structural differences arising from production and changing operating conditions reduce the utilization of available energy. Passive and active balancing methods are used in order to eliminate these imbalances. Due to the slow equalization speed and energy inefficiency of passive balancing circuits, the trend towards active balancing is increasing. In this paper, an active balancing system with a new balancing algorithm that features fast balancing, multiple charge transfers, and suitable for large battery packs used in electric heavy commercial vehicles is proposed to increase usable energy. To test the algorithm, battery module and bidirectional dc-dc converter based active balancing system simulation study has been performed in Matlab-Simulink. The performance of proposed algorithm is compared with other algorithms and simulation results show that the proposed algorithm has better balancing performance.Öğe Artificial neural network-based discrete-fuzzy logic controlled active power filter(Inst Engineering Technology-Iet, 2014) Saribulut, Lutfu; Teke, Ahmet; Tumay, MehmetArtificial neural network (ANN) is a computational algorithm based on the structure and functions of biological neural networks. It is used for modelling of the non-linear systems that cannot be mathematically expressed by the formula and extraction of the system dynamics, expressed by using the complex mathematical equations, such as harmonics. To show the effective usage of ANNs in the power system, the fundamental harmonic of a load with six-pulse thyristor controlled rectifier is extracted with ANN by using the system variables that are difficult to express with each other. Then, a new approach is proposed to generate the reference signal for compensating the harmonics of the current by using discrete fuzzy logic in this study. In addition, a simple and useful method to determine the circuit parameters of the active power filter (APF) is proposed to reduce the rating of the required filter and the capacitor values without affecting its efficiency. Case studies are performed to test the performance of the proposed control algorithm for APF.Öğe Butterfly optimization algorithm based maximum power point tracking of photovoltaic systems under partial shading condition(Taylor & Francis Inc, 2023) Aygul, Kemal; Cikan, Murat; Demirdelen, Tugce; Tumay, MehmetBecause of dust, trees, high buildings in the surrounding area, partial shading conditions (PSC) occur in photovoltaic (PV) systems. This condition affects the power output of the PV system. Under PSC there is a global maximum power point (GMPP) besides there are a few local maximum power points (LMPP). This condition makes the maximum power point tracking (MPPT) procedure a challenging task. In order to solve this issue, soft computing techniques such as gray wolf optimization (GWO), particle swarm optimization (PSO) and Gravitational Search Algorithm (GSA) are implemented. However, the performance of MPP trackers still needs to be improved. The main contribution of this paper is improving the tracking speed by implementing BOA to the MPPT of the PV system under PSC. Thus, in real-time applications a promising alternative presented to the literature to improve the performance of the PV systems under variable PSC because of its fast tracking speed. PV system consists of PV array, boost converter and load are modeled and simulated in MATLAB/Simulink. BOA algorithm is implemented for three different insolation scenarios on the PV array. The results of the BOA algorithm verified by a comparative analysis with PSO-GSA and GWO algorithms. The results show that BOA can give high accuracy and better tracking speed than these algorithms in recent literature.Öğe Capacitor Current Feedback Active Damping for Shunt Active Power Filter with Output LLCL Filter(IEEE, 2017) Buyuk, Mehmet; Inci, Mustafa; Tan, Adnan; Tumay, MehmetA high-order LLCL has excellent attenuation performance of ripple harmonics generated by VSI. The LLCL filter is especially effective at switching frequency to mitigate the switching ripple harmonics. However, like the other high-order filters, LLCL filter has resonance problem, which must be damped to have stable system. In literature, passive damping and active damping methods are proposed for grid-connected VSI. However, the active damping techniques have not been considered for SAPF with LLCL filter yet. Thus, in this paper, LLCL filter for Shunt Active Power Filter with Active Damping method is proposed and analyzed to suppress the resonance of LLCL filter and stabilize the control of SAPF.Öğe Capacitor current feedback active damping for Shunt Active Power Filter with output LLCL filter(Institute of Electrical and Electronics Engineers Inc., 2017) Buyuk, Mehmet; Inci, Mustafa; Tan, Adnan; Tumay, MehmetA high-order LLCL has excellent attenuation performance of ripple harmonics generated by VSI. The LLCL filter is especially effective at switching frequency to mitigate the switching ripple harmonics. However, like the other high-order filters, LLCL filter has resonance problem, which must be damped to have stable system. In literature, passive damping and active damping methods are proposed for grid-connected VSI. However, the active damping techniques have not been considered for SAPF with LLCL filter yet. Thus, in this paper, LLCL filter for Shunt Active Power Filter with Active Damping method is proposed and analyzed to suppress the resonance of LLCL filter and stabilize the control of SAPF. © 2017 EMO (Turkish Chamber of Electrical Enginners).Öğe Designing and performance analysis of solar tracker system: A case study of Çukurova region(Elsevier, 2021) Alici, Hakan; Esenboga, Burak; Oktem, Irfan; Demirdelen, Tugce; Tumay, MehmetToday, solar energy has an important place among the renewable energy sources in the world due to its high energy potential. Therefore the share of solar energy is gradually increasing in electricity generation. It is difficult to get maximum efficiency from the solar photovoltaic (PV) panels installed permanently because they can’t benefit from solar energy continuously. Therefore one of the most effective ways to prevent loss of energy efficiency is the solar tracking systems that provide up to 40% efficiency. In this study, it is aimed to increase the efficiency of solar PV plants by following the sun throughout the day and to maximize the power produced by solar PV panels by exposing it to more light. Therefore a single-axis passive-controlled solar tracker system design is recommended for 42, 000 kWp solar PV power plants in the Çukurova region. The efficiency effect of the proposed tracker system for high-power solar PV plants is examined. By comparing the performance analysis of the proposed solar PV system having a solar tracker system with a fixed angle solar PV system, the effectiveness of the proposed system is revealed for high-power solar PV plants. © 2021 Elsevier Inc. All rights reserved.Öğe DSP controlled voltage disturbance generator(Engineering & Scientific Research Groups, 2018) Savrun, Murat Mustafa; Tan, Adnan; Koroglu, Tahsin; Cuma, Mehmet Ugras; Bayindir, Kamil Cagatay; Tumay, MehmetVoltage disturbance generator (VDG) is a kind of device used to generate voltage disturbances that may occur in the network in order to test and evaluate the performance of the power quality devices such as Dynamic Voltage Restorer (DVR) and Uninterruptible Power Supply (UPS). Some of the voltage disturbance generator systems which are available in the literature and commercially available are complex and expensive while the others are simple, inexpensive but less functional. In this paper, a new transformer based, digital signal processor (DSP) controlled VDG is designed which can generate balanced and unbalanced voltage sag/swell and interruption and can adjust the depth, duration and initiation point of disturbances. The proposed system is composed of bidirectional switches, variable transformers and DSP based controller. 3 phase 20 kVA experimental setup is developed to verify the performance of the designed system with linear and non-linear loads. Moreover, the performance of VDG is also investigated in the compensation tests of DVR and UPS.Öğe Green touch for hydrogen production via alkaline electrolysis: The semi-flexible PV panels mounted wind turbine design, production and performance analysis(Pergamon-Elsevier Science Ltd, 2020) Demirdelen, Tugce; Ekinci, Firat; Mert, Basak Dogru; Karasu, Ilyas; Tumay, MehmetThe novel solar-wind integrated system has been firstly used for hydrogen production in literature with validating theoretical, simulated and experimental studies. This integrated system consists of two main parts; solar-assisted wind turbine and alkaline electrolysis cell. In the first part of this system, the semi-flexible PV panels are smoothly integrated on the vertical axis wind turbine blade. This is a unique design in literature, unlike the hybrid systems that include wind turbines and solar PV panels in published literature. The production and testing of the hybrid integrated system in a single structure were performed both in laboratory conditions and also the system was set up the roof of ATU (Adana Alparslan Turkes Science and Technology University) in Adana. The second part includes hydrogen production via alkaline electrolysis system. The cathodes consist of nickel-coated copper (Cu/Ni) and nickel-vanadium binary coated copper (Cu/NiV), that was produced via electrodeposition technique by self-supporting. The performance of electrodes was compared in 1 M KOH solution via I-V behavior, electrochemical impedance spectroscopy, and long term cathodic polarization analysis. Results showed that polarization resistance was decreased almost 4 times by NiV when comparing the Ni. The surface inhomogeneity values were 0.91 and 0.81 for Cu/Ni and Cu/NiV respectively. The hydrogen gas evolved at the cathodes was also measured and higher volumes were detected for NiV binary coating. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Öğe Implementation of a Novel Hybrid UPQC Topology Endowed With an Isolated Bidirectional DC-DC Converter at DC link(IEEE-Inst Electrical Electronics Engineers Inc, 2020) Koroglu, Tahsin; Tan, Adnan; Savrun, Murat Mustafa; Cuma, Mehmet Ugras; Bayindir, Kamil Cagatay; Tumay, MehmetThis paper introduces an original hybrid unified power quality conditioner (HUPQC) topology as an alternative solution to electrical power quality problems. The proposed HUPQC consists of the shunt hybrid active power filter (SHAPF), the dynamic voltage restorer (DVR), and the isolated bidirectional dc-dc converter (BiDC) located at the common dc link. The SHAPF enables reduction in the voltage rating of the dc-link capacitor, helps to reduce the cost and the size of the dc link, and hence reduces switching losses of the voltage source inverter. Besides the novelty of its topology, dynamic reactive power compensation capability is realized for the first time in the literature within HUPQC concept by achieving adaptively controlling dc-link voltage. The BiDC not only provides isolation and bidirectional power flow between the DVR and the SHAPF but also operates to keep the dc-link voltage of DVR constant against adaptively changing dc-link voltage of the SHAPF. In addition to these, a new hybrid voltage sag/swell detection algorithm based on the combination of the improved Clarke transformation and the enhanced phase-locked loop is developed and introduced. In order to verify the viability and effectiveness of the proposed HUPQC topology, experimental studies are carried out.Öğe Improved adaptive notch filter-based active damping method for shunt active power filter with LCL-filter(Springer, 2018) Buyuk, Mehmet; Tan, Adnan; Tumay, MehmetThe LCL-filter has been recently used with grid-connected converters to mitigate switching ripple harmonics. The LCL-filter presents a better attenuation performance for switching ripple harmonics in comparison with L- and LC-type filters. However, the application of LCL-filter has two basic constraints on the circuit design and the resonance problem. These constraints can be effortlessly overcome for grid-connected converters which operate on the utility fundamental frequency. On the other hand, these constraints become a challenging issue when the LCL-filter is used with shunt active power filter (SAPF) because of the wide operation frequency bandwidth of SAPF. This wide operation bandwidth of SAPF causes a narrow bandwidth for the selection of LCL-filter cutoff frequency and the resonance damping control. In this paper, the application constraints of LCL-filter are discussed and the LCL-filter design is provided for SAPF. In addition, an adaptive notch filter-based single-loop active damping method is developed considering the wide operation bandwidth of SAPF. The proposed method consists of a grid impedance estimation algorithm in order to update notch filter parameters adaptively against grid impedance variations. By the help of the single-loop active damping strategy, the proposed controller does not require any additional sensor for the current measurement of LCL-filter capacitor to damp resonance currents. The stability analysis of proposed controller is performed through pole-zero maps. The proposed method is tested, and its performance is verified with comprehensive case studies of a 400-V 80-kVA SAPF simulation model through MATLAB/Simulink.Öğe Isolated H-bridge DC-DC converter integrated transformerless DVR for power quality improvement(Inst Engineering Technology-Iet, 2020) Savrun, Murat Mustafa; Koroglu, Tahsin; Tan, Adnan; Cuma, Mehmet Ugras; Bayindir, Kamil Cagatay; Tumay, MehmetThis study presents a new H-bridge DC-DC converter-based transformerless dynamic voltage restorer topology (DVR). The proposed system can compensate balanced and unbalanced voltage sag/swell that are the most common electrical power quality problems and offers advantages over conventional DVR topologies by providing the isolation with high-frequency transformer (HFT) rather than bulky injection transformers and by employing shunt converter to eliminate the requirement of an energy storage unit. The system is composed of H-bridge DC-DC converter equipped with a HFT with one primary and three secondary windings and transformerless DVR. The single-phase shift modulation method is used for each series converter independently to provide the bidirectional power flow control of DC-DC converter, whereas in-phase compensation method with a hybrid detection algorithm is used to mitigate voltage sag/swell. An LC filter is employed to attenuate the switching ripple harmonics on the output of the DVR. The performance of the proposed system is verified experimentally on a three-phase, three-wire, 380 V, 10 kVA prototype.Öğe Lightning Electric Field Analysis of a Transformer Using ANSYS Maxwell(Institute of Electrical and Electronics Engineers Inc., 2019) Bal, Selva; Demirdelen, Tugce; Tumay, MehmetLightning strike is a very important phenomenon for all electrical power systems because of over voltage impulse. Thus, lightning analysis is equally important for power issue. In this paper, lightning electric field analysis of an oil type distribution transformer with a 25-kVA power capacity using ANSYS Maxwell simulation program are proposed. Lightning impulse voltage applied to transformer, electric field and voltage distribution of the transformer during lightning are presented with simulation results. Critical regions that can cause breakdown on insulation materials between primary and secondary windings are shown as three dimensionally. Electric field distribution on critical regions on insulation material of two-dimensional model is also shown. The comparison of three and two-dimensional analyses are compared for insulation breakdown during lightning analyses. This paper provides advantage researchers and engineers whom design/produce/choose the transformer bushings/isolators and other insulation materials on a simulation program such as ANSYS. In future, optimization study for insulation materials and partial discharge localization will be done. © 2019 IEEE.Öğe Modeling and experimental validation of dry-type transformers with multiobjective swarm intelligence-based optimization algorithms for industrial application(Springer London Ltd, 2022) Demirdelen, Tugce; Esenboga, Burak; Aksu, Inayet Ozge; Ozdogan, Alican; Yavuzdeger, Abdurrahman; Ekinci, Firat; Tumay, MehmetIn recent years, the optimum and efficient design of the transformer core and conductive materials is the most significant issues to overcome the high-temperature problems. The temperature increases on the transformer materials are directly related to the energy efficiency of it. The overheating of the core and coils of the transformer reduces the amount of energy to be obtained from the transformer. However, copper, core, eddy current and other losses can be minimized by obtaining an optimum design of the transformer for maximum efficiency. Thus, the transformer life and the energy efficiency to be obtained from the transformer are maximized. The temperature rise and temperature distribution of the windings can be monitored by computer technology and the transformer can be safely overloaded and the production cost can be minimized. Also, the operating life of the transformers can be further increased by specifying hot spot temperatures on the transformer coils and core. In this study, 3 kVA and 5 kVA Dyn 11 connected 380/220-V dry-type transformers are optimized by multiobjective swarm intelligence-based optimization methods. The main contribution of this study is to prevent the overheating of the transformers by reducing the losses in the transformer core and coils and to reduce the costs of the transformer. The thermal and electromagnetic analyses of the transformers are realized by ANSYS/Maxwell software program which utilizes the industry-leading ANSYS/Fluent computational fluid dynamics and finite element method solvers. Finally, the experimental analyses are realized under the loaded conditions for the transformers. The experimental results are verified with the simulation results. The optimization, modeling, thermal/electromagnetic analysis and experimental processes are carried out step by step in this study. The transformer manufacturers will realize the optimum cost, efficiency and thermal analysis before transformers are manufactured.Öğe Modeling and experimental validation of dry-type transformers with multiobjective swarm intelligence-based optimization algorithms for industrial application(Springer London Ltd, 2022) Demirdelen, Tugce; Esenboga, Burak; Aksu, Inayet Ozge; Ozdogan, Alican; Yavuzdeger, Abdurrahman; Ekinci, Firat; Tumay, MehmetIn recent years, the optimum and efficient design of the transformer core and conductive materials is the most significant issues to overcome the high-temperature problems. The temperature increases on the transformer materials are directly related to the energy efficiency of it. The overheating of the core and coils of the transformer reduces the amount of energy to be obtained from the transformer. However, copper, core, eddy current and other losses can be minimized by obtaining an optimum design of the transformer for maximum efficiency. Thus, the transformer life and the energy efficiency to be obtained from the transformer are maximized. The temperature rise and temperature distribution of the windings can be monitored by computer technology and the transformer can be safely overloaded and the production cost can be minimized. Also, the operating life of the transformers can be further increased by specifying hot spot temperatures on the transformer coils and core. In this study, 3 kVA and 5 kVA Dyn 11 connected 380/220-V dry-type transformers are optimized by multiobjective swarm intelligence-based optimization methods. The main contribution of this study is to prevent the overheating of the transformers by reducing the losses in the transformer core and coils and to reduce the costs of the transformer. The thermal and electromagnetic analyses of the transformers are realized by ANSYS/Maxwell software program which utilizes the industry-leading ANSYS/Fluent computational fluid dynamics and finite element method solvers. Finally, the experimental analyses are realized under the loaded conditions for the transformers. The experimental results are verified with the simulation results. The optimization, modeling, thermal/electromagnetic analysis and experimental processes are carried out step by step in this study. The transformer manufacturers will realize the optimum cost, efficiency and thermal analysis before transformers are manufactured.Öğe Multiple harmonic elimination-based feedback controller for Shunt Hybrid Active Power Filter(Inst Engineering Technology-Iet, 2017) Tan, Adnan; Bayindir, Kamil Cagatay; Cuma, Mehmet Ugras; Tumay, MehmetThis study presents a multiple harmonic elimination-based feedback controller for shunt hybrid active power filter (SHAPF) to perform an effective harmonic compensation performance in a wide harmonic frequency band. The conventional control methods presented for SHAPF cannot perform an adequate performance, because of the disturbances such as phase delays caused by controller methods and measurement circuitries, tolerances of passive filter components and supply voltage harmonics. In the proposed controller, the conventional feedback controller is improved by using supply side individual current harmonics which are extracted by the synchronous reference frame method. To prevent the performance degradation effects of disturbances, proportional-integral controllers are applied to each d and q components of individual current harmonics. The compensation performance of the proposed method is compared with conventional methods both theoretically and experimentally. The experimental results verify the advanced harmonic compensation performance of the proposed control method.
