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Öğe Attenuating saturated-regulator operation effect of brushless DC motors through genetic-based fuzzy logic estimator(Tubitak Scientific & Technical Research Council Turkey, 2018) Çelik, Emre; Öztürk, NihatAs brushless DC motor (BLDCM) speed approaches base speed, current regulators gradually saturate and lose their ability to perform their regulating task, which causes a dramatic fall in the phase currents and motor power. To control the current to a greater extent and avoid power decline, a new reference current generation technique based on a simple fuzzy logic estimator (FLE) is introduced in this paper. According to motor speed and current command, the developed FLE decides the proper commutation angle a, which is the angle relative to normal commutation instant used for setting the current slew rate during commutation. In this sense, current references are obtained with the same slew rates of commutated phases all the time, ensuring the noncommutation phase current is constant. The validity of the study is widely verified using DSP of TMS320F28335 and it is concluded that promising performance and simplicity are important advantages of our proposal that render it convenient for a BLDCM drive system that requires boosted power in high-speed ranges.Öğe Cogging torque minimization using skewed and separated magnet geometries(2020) Dalcalı, Adem; Kurt, Erol; Çelik, Emre; Öztürk, NihatIn the study, analytical design, analysis and optimization of a 2.5 kW 14-pole, 84-slot permanent magnet synchronous generator(PMSG) have been performed. The performance characteristics of this PMSG such as efficiency, torque, cogging torque andmagnetic flux density are assessed. Then, 3D model of the respective generator is acquired to examine the effect of magnetgeometry on the cogging torque produced. In that context, the effects of splitted and skewed magnet structures are examined. Inthe first design, the magnet is modelled with one piece and the rms value of the cogging torque is found as 436.75 mNm. In thesecond case, a certain skewed slit is made alongside the magnet and that yields a slightly reduced cogging torque of 434.58 mNm.In the other design, the magnet of the first design is divided into two sub-parts, which are then combined together in a skewedfashion. Thus, the value of cogging torque is found as 159.60 mNm. Eventually, by making two certain slits on the last model,cogging torque is further depressed down to 89.95mNm. It is concluded from the obtained results that the last design contributesan improvement in the value of cogging torque up to 80% compared to the initial design.Öğe Frequency Support Studies of a Microgrid Having DG-WTG Using ANFIS and with the Application of HAE-FC and RFB(Taylor & Francis Inc, 2023) Rameshar, Vikash; Sharma, Gulshan; Bokoro, Pitshou N.; Celik, Emre; Öztürk, NihatThe micro-grid (mu-grid) has picked up momentum worldwide with the ability to supply cost-effective, clean, and reliable electrical power to the present-day demand. The practical mu-grids are comprised of non-conventional and conventional sources such as wind turbine generators (WTG) and diesel generators (DG). Due to the encouragement of wind power which is exceedingly sporadic in nature and thus the frequency of the mu-grid is exceedingly vulnerable due to the erratic nature of wind speed. Variations in the load demand have also added to the vulnerability of the mu-grid at distinctive moments of time. Consequently, this paper appears to be a novel plan that utilizes artificial neuro-fuzzy inference system (ANFIS) within the built frequency regulation of the mu-grid. The proposed research has been employed within the mu-grid, and the application outcomes have taken all possibilities, such as load variety at the distinctive moment of time, modification of the load demand on the mu-grid, and step alteration of the wind input. The achieved results are coordinated with a few of the most recent results, which presents the ANFIS ahead over other strategies. Although there is a probable scope for improvement which subsequently involves the fuel cell (FC) with a hydrogen aqua electrolyzer (HAE) unit, as well as a redox flow battery (RFB), that is introduced one at a time in the mu-grid and the results of mu-grid are calculated for various working conditions to show the impact that the ANFIS technology has upon storage devices with regards to the mu-grid architecture.Öğe A hybrid symbiotic organisms search and simulated annealing technique applied to efficient design of PID controller for automatic voltage regulator(Springer, 2018) Çelik, Emre; Öztürk, NihatThis article is motivated by incorporating a hybrid symbiotic organisms search and simulated annealing (hSOS-SA) technique into efficient design of PID controller for automatic voltage regulator (AVR). Symbiotic organism search (SOS) algorithm is contemplated first to optimize parameters of PID controller using a new cost function which considers both time-domain and frequency-domain specifications. The excellence of SOS over some state-of-the-art techniques is confirmed through transient response analysis, root locus analysis and bode analysis for the identical AVR system. To fine-tune controller parameters for enhancing the system stability margin further, simulated annealing algorithm is invoked subsequently at the instant SOS has converged. Extensive numerical results computed from time and frequency response specifications affirm the superiority of proposed hSOS-SA algorithm such that after a minimal overshoot, hSOS-SA tuned AVR system settles to the step reference quickly and follows it with the least steady-state error. Such response is found to ensure a better stability margin than that using original SOS and earlier studies. Finally, robustness analysis is realized to verify that the designed controller is robust with regard to parameter uncertainties.Öğe Improved load frequency control of interconnected power systems using energy storage devices and a new cost function(Springer London Ltd, 2023) Çelik, Emre; Öztürk, Nihat; Houssein, Essam H.This paper investigates the use of energy storage devices (ESDs) as back-up sources to escalate load frequency control (LFC) of power systems (PSs). The PS models implemented here are 2-area linear and nonlinear non-reheat thermal PSs besides 3-area nonlinear hydro-thermal PS. PID controller is employed as secondary controller in each control area and ESDs such as battery energy storage system, flywheel energy storage system and ultra-capacitor are employed to assist LFC task during crest load disturbances. PID controller parameters are optimized by salp swarm algorithm (SSA) using a new cost function. This function is innovative, improving system stability by increasing stability margin of the system. Contribution of the proposed approach are thoroughly justified by contrasting it against the renowned works in the state-of-the-art. The comparison analysis clearly unveils that SSA optimized PID controller with ESDs is able to significantly reduce settling time and unwanted oscillations of frequency and tie-line power deviations with a greater stability margin. Our proposal is also more economic than the existing solutions considering the trade-off between simplicity and effectiveness.Öğe Influence of energy storage device on load frequency control of an interconnected dual-area thermal and solar photovoltaic power system(Springer London Ltd, 2022) Çelik, Emre; Öztürk, Nihat; Houssein, Essam H.The mismatch between power generation and load demand causes unwanted fluctuations in frequency and tie-line power, and load frequency control (LFC) is an inevitable mechanism to compensate the mismatch. For this issue, this paper explores the influence of energy storage device (ESD) on ameliorating the LFC performance for an interconnected dual-area thermal and solar photovoltaic (PV) power system. Initially, to alleviate the frequency and tie-line power deviations, a proportional-integral (PI) controller is chosen and utilized in the system due to its effectiveness and simplicity in practice. For achieving the highest performance from this controller, salp swarm algorithm (SSA) is employed to search for optimal controller parameters by using integral of time-multiplied absolute error (ITAE) criterion. To affirm the contribution of SSA optimized PI controller, it is contrasted with a recent approach utilizing PI controller optimized by genetic algorithm (GA) and firefly algorithm (FA). It is observed that the results acquired for SSA are better than for GA and FA. To improve the system performance further, ESD such as redox flow battery (RFB) famous for its excellent disturbance rejection capability is integrated with the thermal power unit for the first time in the literature. It is divulged from the results that the system performance with RFB has boosted considerably with regard to shorter settling time, less undershoot/overshoot and smaller ITAE value of the frequency and tie-line power fluctuations. According to the sensitivity analysis, our proposal is found robust against system parameters variations and different loading conditions.Öğe Novel fuzzy 1PD-TI controller for AGC of interconnected electric power systems with renewable power generation and energy storage devices(Elsevier - Division Reed Elsevier India Pvt Ltd, 2022) Çelik, Emre; Öztürk, NihatThe work prepared designs a novel fuzzy 1 + proportional + derivative-tilt + integral (F1PD-TI) controller and applies it to automatic generation control (AGC) of power systems (PSs) with renewable energy sources (RESs) based on solar thermal, wind and fuel cells. The capability of this unique controller is initially tested on a two-area reheat thermal power system and then on a multi-source two-area hydrothermal power system. To avert the malfunction owing to improper controller parameters, input scaling factors and other parameters of the F1PD-TI controller are meticulously procured using salp swarm algorithm (SSA) by minimizing the value of integral squared error (ISE) criterion. The worth and contribution of SSA optimized F1PD-TI controller are proclaimed by comparing the results with those offered by several latest controllers. Investigations disclose that the advocated approach beats its serious rivals in terms of shorter settling time, less undershoot/overshoot and smaller ISE value of frequency and tie-line power deviations. As more realistic scenarios, RESs uncertainties in wind speed and solar irradiation are studied and energy storage devices are employed to remedy the problem of surplus/deficient power due to the RESs penetration. Moreover, nonlinearities from governor dead band and generation rate constraint are examined. We realize that significantly better performance and relatively easier design are prominent features of our proposal, which may render it a suitable candidate for practical applications. (C) 2022 Karabuk University. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Sensitivity Factor-Based Congestion Mitigation in DPS Applying Novel Hybrid GWPSO(Taylor & Francis Inc, 2023) Gautam, Anubha; Sharma, Parshram; Kumar, Yogendra; Sharma, Gulshan; Gautam, Anurag; Çelik, Emre; Öztürk, NihatIn a deregulated power system, with a limited power system framework, alleviation in power transfer has been one of the most crucial problems. This alleviation of bulk power transmission came with congestion, where a transmission line transmits power very near the constrained thermal limits. Congestion has to be mitigated for reliable, economical, and stable operation of the power system. Congestion can be mitigated by applying several methods which may be cost-free or non-cost-free. This article presents a cost-free method employing TCSC as a FACTS device. FACTS devices are very costly. To make the TCSC operation economic, LUF and DLUF are used here to optimally locate the device. TCSC is used here as a variable impedance device. A novel hybrid heuristic optimization technique where Grey Wolf optimizer is merged with Particle Swarm Optimizer to optimize the size of TCSC. The proposed method is implemented to regulate the line reactance for congestion mitigation. The power loss and voltage deviation of the system are reduced by the proposed method to relieve the system congestion. The system security margin is enhanced significantly to make the system more reliable. The proposed algorithm is validated on IEEE 30 bus system and is also validated by comparing the results with parent algorithms. The results reveal that the proposed methodology successfully minimized the objectives for mitigating congestion.Öğe A Short-Term Load Demand Forecasting based on the Method of LSTM(Ieee, 2021) Bodur, İdris; Çelik, Emre; Öztürk, NihatElectricity energy is produced from another energy source like fossil source such as oil, coil, natural gas renewable energy sources such as hydraulic, wind, solar. Their storage in high amount is a problematic issue. Therefore, the balance between the power generation and demanded power must be satisfied at all times. This is an obligation especially for companies that generate, transmit and distribute electrical energy. In this paper, a short term load demand forecasting based on a long short term memory (LSTM) is addressed, which may help planning operators for Turkish electricity market. The results of advocated approach were compared by the ones based on recurrent neural network As a result, it is found that the proposed LSTM approach can predict especially daily and weekly demands with an accuracy more than 90%.Öğe Two-degrees-of-freedom PID controller for AC/DC converters(Institute of Electrical and Electronics Engineers Inc., 2019) Öztürk, Nihat; Çelik, EmreThis paper proposes a two-degrees-of-freedom (2DOF) controller for direct power control's outer loop of a three-phase voltage source converter application. The presented scheme is based on voltage oriented (flux), which is realized on unity power factor (UPF) working and lower total harmonic distortion. Also, the 2DOF controller proposed is utilized in the outer loop owing to its high performance in set-point tracking and robustness to load changes. The proposed approach can be utilized in industrial plants in need of DC voltage alongside the advantage of UPF working. The time-domain performance of our proposal is analyzed carefully and the results are presented in Matlab/Simulink environment. © 2019 IEEE.
