İsmail H. Altas

Karadeniz Technical University · Department of Electrical and Electronics Engineering

In this study, a fuzzy logic based smart decisionmaking algorithm has been developed and simulated forlandscape designs to be used in natural air conditioningapplications for energy saving purposes. The plants plantedaround the building should be the type to provide shade andcoolness in summer and allow sunlight to pass through in winter,as well as...

The automatic voltage regulator (AVR) system is commonly used in power systems to remain terminal voltage of generator at a specified level. The terminal voltage level is controlled by utilizing various controllers in an AVR system. Researchers aim to enhance dynamic performance of the AVR system besides minimize steady state error by employing var...

This paper deals with energy efficient locomotion of a wheel-less snake robot. This is very crucial for potential applications of untethered snake robots. The optimum gait parameters for the energy efficient locomotion of the snake robot are obtained with two different multi-objective algorithms based on symbiotic organism search algorithm by consi...

Akıllı şebeke üzerine teknik çalışmalar tüm dünyada ve Türkiye'de devam etmektedir. Akıllı şebekeleri geleneksel şebekelerden ayıran en önemli özelliklerden birisi, akıllı şebekelerin dağıtık üretim yapısına sahip olmasıdır. Bu nedenle talep tarafı yönetimi günümüzün dağıtım şebekelerinde öne çıkan araştırma konularından biridir. Geleneksel şebekel...

Biological snakes can perfectly move on almost all natural environments. Snake robots should be adaptive changing environment in order to have these motion abilities of their biological counterparts. This feature is important for potential applications of snake robots. This work investigates optimal gait parameters for energy efficient locomotion o...

Demand side management (DSM) is an important part of smart electrical grid studies due to high energy efficiency it provides. Effective DSM techniques are hinged on participation level of the customers and control manner of their loads so if there is no fair and appropriate management, customers will not embrace demand side management applications....

Smart grid studies have been increased tremendously for past ten years in order to modernise and solve problems of current electrical grids. One of the aim of the smart grids is to react autonomously to the problems in electrical networks by means of artificial intelligence and decision maker. Fuzzy logic-based embedded control systems simulate hum...

Energy efficient locomotion is critical for untethered snake robots. Despite enhancements in the development of snake robots in terms of modelling and control, a little attention has been given to find optimal locomotion for the snake robot. In this paper, symbiotic organism search algorithm is used to generate the optimum gait parameters for a whe...

Feature selection is crucial to develop a brain computer interface (BCI) system which has high classification accuracy and less computational complexity in especially a large feature space. Feature selection (FS) problem has been solved by many various methods. Among these methods, especially evolutionary computation (EC) techniques have gained a l...

Voltage control is performed to reduce network losses in power systems. Automatic Voltage Regulator (AVR) system is commonly used in power systems to keep output voltage on a constant value defined in a specified range. In order to improve dynamic response of an AVR system and minimize obtained steady state error, researchers focus on developing co...

With constant population growth and the rise in technology use, the demand for electrical energy has increased significantly. Increasing fossil-fuel-based electricity generation has serious impacts on environment. As a result, interest in renewable resources has risen, as they are environmentally friendly and may prove to be economical in the long...

In this paper, kinematic and dynamic modelling of a wheel-less snake robot that has more potential for adapting to the environment is implemented in Matlab/Simulink and effect of friction between its body with the ground, which plays a highly important role in some snake locomotion such as lateral undulation on motion is analyzed. Moreover, the rel...

Voltage control is performed to reduce network losses in power systems. Automatic Voltage Regulator (AVR) system is commonly used in power systems to keep output voltage on a constant value defined in a specified range. In order to improve dynamic response of an AVR system and minimize obtained steady state error, researchers focus on developing co...

Stewart platform or other parallel manipulators with a Stewart structure are commonly used in flight simulators, surgical operations, medical rehabilitation processes, machine tools, industrial applications, etc. Therefore, researchers have paid attention to position control of these manipulators in addition to their design and development process....

This paper introduces design and utilization of a MATLAB graphical user interface (GUI) platform to forecast day ahead hourly Photovoltaic (PV) panel power by using forecasted day ahead global horizontal solar radiation. This platform, which would be a useful and practical tool for researchers who are study on energy management, planning and foreca...

Abstract: In this paper, output voltage of a three phase uninterrupted power supply is controlled using finite control set model predictive control. A discrete time disturbance observer is used to estimate the disturbance load current. A robust method is proposed to determine the gain matrix of the observer. This optimal gain matrix was computed us...

In this paper, output voltage of a three phase uninterrupted power supply is controlled using finite control set model predictive control. A discrete time disturbance observer is used to estimate the disturbance load current. A robust method is proposed to determine gain matrix of the observer. This optimal gain matrix was computed using linear mat...

Electricity generation from renewable energy sources is increased day by day. Accurate estimation of electricity generation from the renewable energy sources which have intermittent and variable characteristics is a requirement to ensure stable operation of the electrical grid. In this study, a multi-layer artificial neural network (ANN) system, wh...

Solar energy is a renewable energy source which has intermittent and variable characteristic. Solar irradiation must be predicted in advance in an electrical grid which has solar energy based electrical power generation systems in order to operate the electrical grid stable and efficient. In this study, a multi-layered, feed forward artificial neur...

This paper presents an optimized fractional order controlled cascaded synchronous buck–boost converter for a wave/ultra-capacitor (UC) hybrid energy system. Due to the irregular wave dynamics, the extracted energy from a wave energy converter (WEC) shows aperiodic voltage swells and sags. To eliminate the stochastic wave effects on the electrical s...

This article is focused on increasing the tracking performance of a developed ankle rehabilitation robot subject to external disturbance. A plug-in-type repetitive controller cascaded to a proportional–integral–derivative controller is designed and implemented in order to make improvement in the tracking ability of the parallel mechanism while perf...

Wind energy is a resource that does not require any fuel or feedstock to be treated, refined or transported. It does not produce air pollution and hazardous waste. Because of these, wind energy, one of the major renewable energy sources, has been widely used in recent years. In this work, a three-phase distribution static synchronous compensator (D...

Maximum power point tracking (MPPT) algorithms are used to maximize the output power of the photovoltaic (PV) panel under different temperature and irradiance conditions in photovoltaic energy sources (PVES). In this paper, a novel MPPT method based on optimized artificial neural network by using hybrid particle swarm optimization and gravitational...

Demand side management is one of the key issues in smart electrical grid studies. Power demand of consumers can be managed via demand response(DR) programs. Task scheduling (TS) based demand response is one of the DR schemes. Objective of the TS approach is to schedule activation time of the appropriate time-shiftable loads to reduce power consumpt...

Modern electrical power systems are facing complex challenges, arising from distributed generation and intermittent renewable energy. Fuzzy logic is one approach to meeting this challenge and providing reliability and power quality. The book is about fuzzy logic control and its applications in managing, controlling and operating electrical energy...

Power quality is one of the important issues in wind energy systems as in all renewable energy systems. Reactive component of current in distribution systems causes negative effects on the network, including power loses, voltage drop, and reduced line capacity. Static Synchronous Compensator (STATCOM) has been used increasingly instead of conventio...

In this paper, a simulation study of output current control of an uninterruptible power supply is carried out. Model Predictive Control method is used for controller design. The discrete model of a three phase inverter is used as a system model. Variable DC supply is used as a PV system model for the input voltage of the inverter. The simulation re...

In this paper, the location and the size of capacitors to be installed in radial distribution systems are determined by using the Symbiotic Organism Search (SOS) algorithm which is a new and powerful metaheuristic optimization technique in order to increase the efficiency by reducing the power losses in distribution systems and to deliver energy mo...

In this study, both the reactive power and amplitude of the voltage on the load are controlled in the Fuel Cell (FC)/Solar Panels (SP) hybrid system. Compensation is required to reduce harmonics and to correct power factor in power systems. STATCOM, a more advanced version of these compensation systems, has started to be widely used. STATCOM has a...

In this paper, a FACTS based dynamic switched C-type filter (DSCTF) compensator scheme for distribution systems is presented with different load characteristics and control strategies. In order to suppress power quality problems and increase overall energy utilization efficiency; design and digital realization of the DSCTF consisting of dynamic con...

DC-DC converters are highly considered in recent years because of the increased use of the renewable energy sources (RES). Since the energy output of the RES is depended on the weather conditions, DC-DC converters are used to regulate variable RES output. In this study, simulation based model predictive control (MPC) of a DC-DC buck converter is ca...

Ankle rehabilitation robots have recently attracted great attention since they provide various advantages in terms of rehabilitation process from the viewpoints of patients and therapists. This paper presents development and evaluation of a fuzzy logic based adaptive admittance control scheme for a developed 2-DOF redundantly actuated parallel ankl...

This paper presents a flower pollination algorithm (FPA) tuned fuzzy logic controlled (FLC) synchronous buck converter (SBC) for an integrated wave/ supercapacitor (SC) hybrid energy system. In order to compensate the irregular wave effects on electrical side of the wave energy converter (WEC), a SC unit charged by solar panels is connected in para...

The purpose of this paper is to introduce the status of wave energy conversion (WEC) technologies from a different perspective. Past studies based on WEC systems are summarized and classified in terms of WEC system components to clearly reveal the performance, efficiency and development of WEC technologies over the last two decades. It has been pro...

In this paper, different controller techniques based on particle swarm optimization (PSO) algorithm are proposed to control the water level of a steam generator with multiple input-multiple output (MIMO) characteristics. The techniques employed are classical proportional+integral+derivative (PID) control, fuzzy logic control (FLC) and fuzzy tuned p...

Bu makalede Güneş Panelleri (GP) ve Yakıt Pillerinden (YP) oluşan karma yenilenebilir enerji üretim sistemi için 5 seviyeli Statik Senkron Kompanzatör (STATCOM)’un benzetim çalışması yapılmıştır. Güneş panellerinin yetersiz güneş ışığı ve gündüz-gece durumu gibi ortam şartlarından dolayı güç üretemediği durumlarda yüklerin enerjisiz kalmasını önley...

Geleneksel olarak kullanılan statik var kompanzatörler ve sabit mekanik anahtarlamalı kondansatör grupları iletim ve dağıtım sistemlerinde güç kalitesini arttırmak için kullanılmaktadır. Son yıllarda, bazı güç kalitesi iyileştirici cihazlar enerji sistemlerinde reaktif güç kompanzasyonu için geliştirilmiştir. Esnek Alternatif Akım İletim Sistemleri...

In electricity generation, there is a tendency towards renewable energy sources in order to supply the increased electricity demand and in an effort to generate electricity with less environmental damages. The Sun is a significant renewable energy source and photovoltaic (PV) panels are one of the most commonly used systems in electricity generatio...

Model Öngörülü Kontrol yaklaşımı kullanılarak DA-DA alçaltan dönüştürücü çıkış geriliminin kontrolü benzetim ortamında incelenmiştir. Değişken yük ve değişken giriş gerilimi sisteme eklenerek denetleyicinin etkisi incelenmiştir. Klasik denetleme yöntemlerinden PID denetleyici ile karşılaştırmalı olarak incelenmiştir. Matlab/Simulink ortamında siste...

Human–robot interaction is inherently available and used actively in ankle rehabilitation robots. This interaction causes disturbances to be counteracted on the rehabilitation robots in order to reduce the side effects. This paper presents a fractional order proportional–integral–derivative controller to improve the trajectory tracking ability of a...

Rüzgar enerji sistemlerinde önemli bir kavram olan güç kalitesini artırmak için geleneksel olarak kullanılan mekanik anahtarlamalı kondansatör gruplarının ve static var kompanzatörlerinin yerine günümüzde giderek yaygınlaşan Statik Senkron Kompanzatör (STATCOM) kullanılmaya başlanmıştır. Dağıtım sistemlerinde kullanılan STATCOM cihazları Dağıtım ST...

Bu makalede Yakıt Pili (YP) ve Güneş Panelleri (GP) karma sisteminde hem reaktif güç kontrolü hem de yük üzerindeki gerilimin genliğinin denetimi yapılmaktadır. Güç sistemlerinde hem harmonikler azaltılması hem de güç faktörünün düzeltilmesi için kompanzasyon yapılması gerekmektedir. Bu kompanzasyon sistemlerinin daha gelişmişi olan STATCOM yaygın...

Dalgaların karakteristik yapıları gereği, doğrudan sürüşlü dalga enerji sistemlerinde (DES) karşılaşılan gerilim düşümleri ve dalgalanmaları, üretilen bu enerjinin direkt olarak yüke bağlanmasını engellemektedir. Bu nedenle yük bağlantısından önce güç elektroniği devreleri ile birlikte enerji depo üniteleri veya harici enerji kaynaklarına ihtiyaç d...

Özet: Artan elektrik talebinden ve fosil kaynaklardan elektrik üretiminin çevreye verdiği olumsuz etkilerden dolayı elektrik üretiminde yenilenebilir enerji kaynaklarına yönelim söz konusudur. Güneş enerjisi en başta gelen yenilenebilir enerji kaynaklarından biridir. Güneş enerjisinin elektrik üretiminde kullanılması fotovoltaik etkinin keşfinden s...

Özet: Güneş enerjisi yenilenebilir bir enerjidir. Güneş enerjisinden elektrik üretmek için çoğunlukla Fotovoltaik (FV) sistemler kullanılır. Bina çatıları FV sistemlerin uygulama alanlarından biridir. Devlet veya elektrik sağlayıcısı tarafından verilen teşviklerle çatıya kurulu FV sisteme sahip her bir konut elektrik üreten küçük birer elektrik san...

This paper presents one of the latest nature-inspired meta-heuristics algorithms known as Cuckoo Search Algorithm (CSA) to solve optimal capacitor placement and sizing (OCPS) problem in radial power systems for the purpose of maximizing annual net saving by reducing the power losses with the acceptable voltage ranges. In the proposed algorithm, dis...

Electrical power systems have been developed to more advanced structures called as “smart grids”. Among many other issues, demand side management (DSM) is one of the important instruments of the smart grids. DSM techniques increase the efficiency of the grid, and modify consumer’s electrical demand via demand response (DR) programs using financial...

The importance of an automobile's headlamps in the dark is inferable from the results of studies. Various regulations are available in order to arrange the required illuminance values at certain positions on the road. The designed and produced headlamps have to satisfy the requirements of these regulations. Manual measurement tools, such as the lux...

This paper presents optimal tuning of the controller parameters of a proportional-integral-derivate (PID) controller for an automatic voltage regulator (AVR) system using a heuristic gravitational search algorithm (GSA) based on mass interactions and Newton's law of gravity. The determination of optimal controller parameters is considered an optimi...

This paper introduces an adaptive fuzzy PI controller (AFPIC) for a flexible AC transmission system (FACTS) based dynamic power filter (DPF) to be used in wave energy conversion systems. The new FACTS device stabilizes the DC-common bus voltage, reduces quality of power troubles, and enhances energy utilization by acting as a bus quantity enhancer...

This paper proposes a novel control system for control of a hybrid photovoltaic PV farm utilization with alternative power source for DC type loads. A controller consisting of three different controllers is mainly used to regulate the DC-DC converter and also to control power flow from alternative power source to reduce a weighted total sum of all...

In this paper, a system given in state space model has been controlled. To control this system, two different controller have been used, one of them is conventional PI controller. PI controllers are used industrial application enormously, but if the system doesn't have a mathematical model, PI controllers fail. Second controller type used in this p...

System modelling and simulation are essential in engineering especially in automatic control systems (ACS) engineering. At many universities, undergraduate curricula include systems and control courses with dynamic modelling and simulations in their syllabi. In order to design a controller for a physical system, one has to know the operational beha...

Bu calismada ruzgar turbinlerinden maksimum verimin elde edilebilmesi icin kullanilan farkli bir Maksimum Guc Noktasi Izleyici (MGNI) teknigi anlatilmaktadir. Deneysel olarak kurulan ve testleri yapilan sistem; biri motor digeri generator olarak calisan birbirine akuple edilmis asenkron makinalardan olusan ruzgar turbin emulatoru, transformator, yu...

In this paper, a combined photovoltaic (PV) solar panels (PVSP) and Super capacitor (SC) renewable power generating unit feeding 3-phase, 380V/ 50 Hz loads is studied. The renewable power generation unit is operated as an off-grid setup. SC is used to maintain the required load power demand during lower power generation stages by PV system due to c...

An intelligent energy management system (IEMS) for maintaining the energy sustainability in renewable energy systems (RES) is introduced here. It consists of wind and photovoltaic (PV) solar panels are established and used to test the proposed IEMS. Since the wind and solar sources are not reliable in terms of sustainability and power quality, a ma...

In this study, a direct wheel drive electric vehicle based on an electronic differential system with a fuzzy logic sliding mode controller (FLSMC) is studied. The conventional sliding surface is modified using a fuzzy rule base to obtain fuzzy dynamic sliding surfaces by changing its slopes using the global error and its derivative in a fuzzy logic...

Gravitational Search Algorithm (GSA) is a novel stochastic optimization method inspired by the law of gravity and interaction between masses. This paper proposes a novel modified hybrid Particle Swarm Optimization (PSO) and GSA based on fuzzy logic (FL) to control ability to search for the global optimum and increase the performance of the hybrid P...

In this study, a different Maximum Power Point Tracking (MPPT) technique to obtain maximum efficiency from wind turbines is mentioned. The system, which is experimentally established and tested, consists of a wind turbine emulator, which consists of asynchronous machines coupled to each other and one of them acts as the motor while the other is the...

This paper presents a fuzzy logic control approach for trajectory tracking of Stewart platform which is a six degrees of freedom parallel manipulator. In order to have a robust tracking a fuzzy logic controller, convenient for nonlinear complex systems, is developed. The performance of the developed FLC is compared with classical PID controller. Th...

In this study, a fractional-order PID (FOPID) controller is designed to control a DC-DC boost converter in a PV-system. Because of the nonlinear V-I characteristic of a PV-panel, a power electronic interface is required to obtain a desired and fixed voltage level. In order to obtain the best system performance, parameters of the proposed controller...

Photovoltaic (PV) generators, which convert sunlight to electricity directly, exhibit nonlinear current versus voltage characteristics because of their structure. For this reason a PV generator has a unique maximum power point under any atmospheric condition. Using of maximum power point tracking (MPPT) systems have importance to utilize the incide...

Bu çalışmada laguerre fonksiyonları kullanarak doğru akım motor hızının sürekli zamanlı model öngörülü kontrolü yapılmıştır. Kontrolör tasarımında durum uzayı modeli kullanılmıştır. Optimal giriş işaretinin elde edilmesinde kontrol işaretinin türevi kullanılmış ve işaretin elde edilmesinde Laguerre fonksiyonlarından yararlanılmıştır. Çalışmanın ası...

zet Güneş enerjisi çevrim sistemleri yenilenebilir ya da alternatif enerji kaynakları içerisinde önemli bir yere sahiptir. Bu çalışmada, güneş enerji çevrim sistemleri için MATLAB/GUI tabanlı bir eğitim seti hazırlanmıştır. Bu eğitim setinde bir diyotlu ve iki diyotlu güneş pili modelleri düşünülmüştür. Kullanıcı, güneş pilinin tüm parametrelerini...

zet Günümüzde, temiz enerji kaynakları ya da yenilenebilir enerji kaynaklarından fotovoltaik sistemlerin (FV) kullanımı giderek artmaktadır. Bu çalışmada bir diyotlu FV pilin matematiksel modeli kullanılarak benzetim modeli ve bu modelin seri-paralel bağlanması ile FV panel modeli oluşturulmuştur. FV panelin farklı çevresel koşullar altında benzeti...

This paper represents a novel FACTS based on modulated power filter compensator (MPFC) for voltage stabilization in renewable wind energy with AC grid connected. Self-excited squirrel-cage induction generator (SEIG) is driven by a wind turbine for renewable a wind energy system. In order to improve voltage stabilization and energy utilization, the...

The paper presents a novel FACTS based Dynamic Voltage Stabilization Scheme (DVSS) for Distribution/Utilization Grid systems. The FACTS device is controlled by using multi loop error driven dynamic control strategies. In order to do this Matlab/Simulink/Simpower Software with GUI interface has been used for all digital simulation models of the all...

Design and utilization of a Virtual Photovoltaic Systems Laboratory for undergraduate curriculum are introduced in this paper. The laboratory introduced in this study is developed to teach students the basics and design steps of photovoltaic solar energy systems in a virtual environment before entering the field. The users of the proposed virtual l...