Erdal Irmak

Gazi University · Department of Electrical and Electronic Engineering

This paper introduces an innovative demand response energy management system tailored for smart homes, aimed at optimizing appliance usage in real time. The system considers dynamic pricing tariffs, device characteristics, usage patterns and user behavior to achieve efficient energy management. Unlike conventional systems, the proposed approach int...

In this study, a digital twin model of a hydroelectric power plant has been created. Models of the entire power plant have been created and malfunction situations of a sensor located after the inlet valve of the plant have been analyzed using a programmable logic controller (PLC). As a feature of the digital twin (DT), the error prediction and prev...

Bu çalışma, Microsoft tarafından geliştirilen ve organizasyonlar için kritik bir bilgi teknolojileri bileşeni olan Windows Aktif Dizin Etki Alanı Servisini ele almaktadır. Bu servis, sunduğu yüksek işlevsellikle dünya genelinde yaygın bir şekilde kullanılmaktadır, ancak aynı zamanda kurumları siber saldırılara karşı savunmasız kılan bir hedef halin...

In this paper, an event-triggered distributed secondary control, along with an energy management algorithm, was developed to ensure the voltage stability and power management of a DC microgrid containing batteries and renewable energy sources, such as PV systems and wind turbines. The energy management algorithm, employing fuzzy logic control, gove...

Although distributed secondary control helps control microgrids, it can provide insufficient performance in some cases where the system includes both renewable energy sources (RESs) and energy storage systems (ESSs). Therefore, an improved distributed secondary control structure is proposed in this study to improve efficiency and reliability in isl...

The growing interest in electric vehicles (EVs) as a solution to the environmental challenges and scarce energy resources, has created a myriad of challenges and opportunities. EVs operate on clean energy sources making them energy-efficient and sustainable. Nevertheless, the adoption of this mode of transport depends on finding a satisfactory reso...

Electric vehicles (EVs) have emerged as a promising solution to address environmental concerns and transform the transportation sector. This paper examines the state-of-the-art EVs, encompassing their history, definition, and different types. The advantages and limitations of each type are compared and contrasted, providing insights into their uniq...

This paper provides a comprehensive review of the future digitalization of microgrids to meet the increasing energy demand. It begins with an overview of the background of microgrids, including their components and configurations, control and management strategies, and optimization techniques. It then discusses the key digital technologies that can...

This paper provides a comprehensive overview of organic photovoltaic (OPV) cells, including their materials, technologies, and performance. In this context, the historical evolution of PV cell technology is explored, and the classification of PV production technologies is presented, along with a comparative analysis of first, second, and third-gene...

The electric power system is undergoing a significant transformation driven by advances in digital technologies. This article provides a comprehensive and detailed analysis of recent advances and the future outlook of electric power systems, with a particular emphasis on the impacts of digital transformation. By conducting a thorough examination of...

The use of renewables can make it more challenging to maintain a balance between supply and demand in microgrids due to their variable generation profiles. To address this issue, microgrids can be designed to be grid-interactive or to include energy storage units, or both. Additionally, demand-side management (DSM) strategies can be implemented to...

The power efficiency of photovoltaic energy systems mainly depends on climatic conditions such as solar irradiation and temperature. Therefore, several types of maximum power point tracking (MPPT) algorithms have been proposed to get the maximum efficiency. However, traditional algorithms perform insufficient response for reaching global maximum po...

A comprehensive and comparative review of control strategies for power-sharing operation in DC microgrids are presented in the paper. Since a microgrid consists of distributed generation sources and energy storage units, a control layer is required to manage the power-sharing operation between them. For this purpose, the control schemas used in DC...

The power system inertia based on the kinetic energy stored in synchronously connected rotating machines has a crucial effect on the frequency stability. As long as the use of renewables is increased, the share of conventional generators in electrical energy generation is decreased. Thus, the existing rotational inertia in the power system is reduc...

İnternet ve bilişim sistemleri üzerinde işlenen suçları tespit etmek amacıyla gerçekleştirilen adli bilişim incelemelerinin önemi, her geçen gün daha iyi anlaşılmaktadır. Bu minvalde suç ve suçlunun tespiti konusunda hukuka uygun dijital delillerin elde edilmesinin önemi çok büyüktür. Adli bilişim incelemelerinde, birçok farklı yöntem ile dijital d...

Covid-19, ilk olarak Aralık 2019’da Çin’de görülen bir virüs olmakla birlikte yayılımı ve şiddeti nedeniyle 11 Mart 2020’de Dünya Sağlık Örgütü tarafından küresel salgın olarak tanımlanmıştır. Aynı tarihte Türkiye’de de ilk vakanın görülmesiyle alınan yerinde ve zamanında önlemler sayesinde salgın eğrisindeki yükselişin önlenmesinde büyük bir başar...

Bu çalışmada, kablosuz ağlarda gerçekleştirilen şifre kırma saldırılarının ve Linux tabanlı sunucu sistemlerine yönelik önemli bir tehdit olan SSH kaba kuvvet saldırılarının, oluşturulan uygulama ortamlarında deneysel olarak test ve analizi gerçekleştirilmiştir. Ayrıca SSH kaba kuvvet saldırılarının, ELK-SIEM sistemi ile gerçek zamanlı ve ilişkisel...

Since renewable energy sources such as PV and wind provide intermittent energy generation, this paper presents an advanced DC/DC converter that is able to set its operational mode automatically to either multi-input multi-output (MIMO) or single-input multi-output (SIMO) depending on the input source conditions. Power flow is controlled through the...

Haberleşme, enerji, ulaşım ve sağlık hizmetleri gibi merkezi altyapı sistemleri, ülkeler için kritik altyapı sayılmaktadır. Bu sistemlerin yönetimini sağlayan operatörlerin yorgunluk durumları son derece önem arz etmektedir. Özellikle merkezi SCADA sistem operatörlerinin kısa süreli bir dalgınlık veya dikkatsizlikleri, ciddi bir olayın veya alarmın...

Abstract— Due to the nature of renewable energy, the variability in generation is high. The grid operator experiences operational concerns arising from the variable generation. In this study, distribution and differences of power angle in the grid are discussed and the effects of wind energy generation changes on power angles are analyzed in detail...

In this study, multi-input multi-output DC/DC converter topology is presented for both multisource operation and voltage unbalancing of Neutral Point Clamped (NPC) inverters. Multisource operation is provided with multi-input feature of proposed converter model. The unbalanced capacitor voltages in NPC inverter leading to increase the harmonics are...

In this study, Perturb and Observe Maximum Power Point Tracking (P&O MPPT) algorithm and Model Predictive Control (MPC) algorithm are combined to improve the dynamic performance of the control structure of boost converters used in renewable energy systems. For this purpose, a digital control method that does not need any comparator is developed. Th...

Electrical energy generation, transmission and distribution systems are evaluated in terms of national security dimension and defined as critical infrastructures. Monitoring and controlling of these systems are provided by Industrial Control Systems (ICS) or Supervisory Control and Data Acquisition (SCADA) systems. According to the latest advances...

Supervisory control and data acquisition (SCADA) systems play an important role in electrical power systems, which is one of the most critical infrastructures. They usually include digital controllers like PLCs to realize the automation of electromechanical processes and to accomplish the real time services. Ensuring a secure communication between...

This study focuses on smart home applications those especially use the wireless sensor networks to ensure the communication between the home devices and the central control unit. For this purpose, a prototype smart home network is designed which consists of some basic devices like refrigerator, television, washing machine etc. and also ZigBee nodes...

Design and simulation of a new inverter scheme are reported in the paper. The inverter is especially developed for an axial flux permanent synchronous generator (AFPMSG), which can be used for low power wind energy systems. The system includes a battery charge unit in addition to the inverter. Initially, the permanent magnet synchronous generator (...

This study presents an advanced computer interactive system for automatic parallel connection of synchronous generators and load sharing control between them. Because of its high operation speed and precision, a dsPIC microcontroller has been used in the study to control the conditions for paralleling and then to realize the connection, to transfer...

Bilgi güvenliği alanında risk değerlendirmesi siber saldırılara karşı alınacak önlemlerin en başlarında yer almaktadır. Bunun gerçekleştirilebilmesi için tehdit türlerinin çok iyi analiz edilmesi gerekmektedir. Bu çalışmada, kritik bilgi sistemlerine yönelik siber saldırı gerçekleştiren saldırganların profilleri incelenmiş, saldırı ağacı modeliyle...

Reactive power compensation of dynamic loads is one of the most important topics in electrical power systems. Therefore, various compensation techniques are continuously being developed in order to improve the power quality. In this context, this paper deals with the simulation and the analysis of a powerful Fixed Capacitor-Thyristor Controlled Rea...

Smart homes can be defined as homes which can satisfy the needs of comfort with the help of wireless modules. The smart home technologies make the daily life easier and offers safer, more comfortable and economic life spaces. The smart home systems allow the user to monitor and also control all electronic and electrical devices in the house. In thi...

Recently, growing electrical energy market and increasing integration of renewable energy sources (RES) in power systems have lead to new challenges on network planning step and operation, thus it is required to investigate and analyze properly the impacts of integrated RES on the power system. In this paper, the electricity transmission network wi...

This study presents integration of a real-time energy monitoring and control system with an advanced reactive power compensation unit based on fixed capacitor-thyristor controlled reactor (FC-TCR). Firing angles of the thyristors located in the FC-TCR are controlled by a microcontroller in order to keep the power factor within the limits. Electrica...

Bilgi güvenliği alanında risk değerlendirmesi siber saldırılara karşı alınacak önlemlerin en başlarında yer almaktadır. Bunun gerçekleştirilebilmesi için tehdit türlerinin çok iyi analiz edilmesi gerekmektedir. Bu çalışmada, kritik bilgi sistemlerine yönelik siber saldırı gerçekleştiren saldırganların profilleri incelenmiş, saldırı ağacı modeliyle...

Günümüzde birçok endüstriyel uygulamada mikrodenetleyici tabanlı kontrol ve izleme sistemleri kullanılmaktadır. Bu çalışmada, son zamanlarda kullanımı gittikçe yaygınlaşmakta olan dsPIC (Digital Signal Controller) mikrodenetleyicisi ele alınmıştır. dsPIC, özellikle yüksek hız ve tepki zamanı gerektiren uygulamalarda düşük maliyetli ve etkili çözüml...

This paper presents, a fault simulation on a microgrid consisting of a wind turbine, a solar panel and fuel cell. The power produced by different sources is combined on the same DC bus and converted to AC form using a three phase inverter in order to transfer it to 3-phase AC load. The system takes some precautions against some undesired situations...

This study introduces a novel and powerful speed control system with computer interface for wound-rotor induction machines (WRIM). In order to improve the sensitivity and stability of the control process, a high-speed digital signal processor (DSP) is used as the main controller. A serial resistor is connected to rotor side of WRIM to control the o...

This study proposes a parallel connection method for hybrid renewable energy sources connected on the same bus to obtain an optimum load sharing system among them. Although output voltage of the energy sources connected on the bus changes abruptly, the system continuously adjust the output voltage to a pre-defined constant reference value. Power sh...

The use of renewable energy sources are rapidly increasing as alternatives to conventional sources. As Turkey having a great potential of renewable sources, the consciousness of community is a very significant issue for the development in this area. A survey of renewable energy awareness is conducted in this paper; implemented on university student...

In this study, a highly instructive and novel remote laboratory platform using up to date software and hardware units is designed to teach main concepts of Electrical Engineering with the help of web-based simulations and remote accessible experiments in real time. Interactive experimental applications for direct current (DC) motors and several ele...

Data mining is a process of getting out useful information from data stacks. One of the most common application areas is to use classification of algorithms that estimate the future events by past experiences. In this context, in order to predict future events, a data warehouse is created by using the background of students which includes demograph...

In this paper, an experimental application focused on energy quality observation is developed. The required parameters are obtained from the system by the designed electronical measurement cards and then transferred to the computer. As the controller a Data Acquisition card is used and also a user-friendly web interface is prepared for computing an...

In this study, parallel connection of separate voltage sources has been realized using cuk converters. For this aim, output voltages of converters are measured continuously and then fixed to a reference value. The PWM signals which are required to control the converters and to sense the current and voltage signals are generated by an FPGA. Since th...

In this paper, an experimental application focused on energy quality observation is developed and power factor correction for the electrical power systems is simulated. The required parameters are obtained from the system by electronic cards and then transferred to the computer. As the controller a (DAQ) Data acquisition card is used and also a use...

In this study, a step motor training set is designed for educational purposes to resolve the lack of application on electrical machines and control techniques education. Forward and reverse rotation of the motor, application of half step and full step movement and speed control can be performed with designed microprocessor-based circuit and also vi...

In this study, energy monitoring system of a medium scale industrial plant is achieved through a computer interface both in real time and retrospective using recent data. In order to measure the energy, a measurement card is designed to convert the voltage and current signals in suitable levels for a programmable logic controller (PLC). Current and...