Yüksel Oğuz

Power quality control and design of power converter for variable-speed wind energy conversion system with permanent-magnet synchronous generator.

The control strategy and design of an AC/DC/AC IGBT-PMW power converter for PMSG-based variable-speed wind energy conversion systems (VSWECS) operation in grid/load-connected mode are presented. VSWECS consists of a PMSG connected to a AC-DC IGBT-based PWM rectifier and a DC/AC IGBT-based PWM inverter with LCL filter. In VSWECS, AC/DC/AC power converter is employed to convert the variable frequency variable speed generator output to the fixed frequency fixed voltage grid. The DC/AC power conversion has been managed out using adaptive neurofuzzy controlled inverter located at the output of controlled AC/DC IGBT-based PWM rectifier. In this study, the dynamic performance and power quality of the proposed power converter connected to the grid/load by output LCL filter is focused on. Dynamic modeling and control of the VSWECS with the proposed power converter is performed by using MATLAB/Simulink. Simulation results show that the output voltage, power, and frequency of VSWECS reach to desirable operation values in a very short time. In addition, when PMSG based VSWECS works continuously with the 4.5 kHz switching frequency, the THD rate of voltage in the load terminal is 0.00672%.

Modeling of hybrid wind‐gas power generation system and adaptive neuro‐fuzzy controller to improve the system performance

In this study, dynamic modeling of the hybrid wind‐gas power generation system (HWGPGS) is realized by using the MATLAB/Simulink program for purpose of meeting the electric energy needs of small settlement units far from city centers or energy distribution networks. Besides, Adaptive Neuro‐Fuzzy Inference System (ANFIS) is used to ensure electrical output magnitudes of the hybrid power generation system at a desired operating performance. The components that build up the hybrid power generation system and its functions in the system are explained. In case the HWGPGS is loaded with different consumer loads, analysis of electrical magnitudes of the system is made through simulation results. As it can be seen from the results of simulation study realized for the hybrid power generation system, output electrical magnitudes of the ANFIS controlled system reach to desired operating values in a short time.

Short term load forecasting for a micro region using NNs and regression models

Thanks to todays advancing technology, some techniques have been developed to make future oriented forecast on energy generation, transmission and distribution subjects. In literature, load forecasting studies are generally realized for macro size settlement units. However, determination of parameters that effect load forecasting in macro size settlement units is very difficult. In this study, by considering a micro size settlement unit (Güney district of Denizli province), factors that may affect the load demand were examined. Then, by selecting popular methods used in the literature, load forecasting for the region was realized. Finally the results obtained from the models were compared.

Energy Flow Control with Using Arduino Microcontroller in Off-Grid Hybrid Power Generation System Including Different Solar Panels and Fuel Cell

This study included a practice for efficient and effective energy use when control algorithms related to energy flow of hybrid energy generation system consisting of different types of solar panels (monocrystalline, polycrystalline and thin film) and fuel cell were performed. An Arduino microcontroller–based control system was designed in order to use the energy generated efficiently and effectively in hybrid power generating systems which consist of solar panels, battery packs, fuel cell and direct current and alternating current loads. Routing of energy was performed by relays, and the processes such as monitoring and saving of data belonging to the energy generating system and manual control of the relays optionally were performed via a LabVIEW program on the computer. The electrical energy produced by each solar panel, energy demand of the load and charge–discharge conditions of the batteries were monitored through the control system designed for energy flow control. The data were analyzed and the performances of these three control algorithms were compared. It was determined which of these three different control algorithms had the most effective and efficient energy usage.

Approximate and Three-Dimensional Modeling of Brightness Levels in Interior Spaces by Using Artificial Neural Networks

In this study, artificial neural networks were used to determine the intensity of brightness in interior spaces. The illumination elements to illuminate indoor spaces were considered, not individually, but as a system. So, during the planned maintenance periods of an illumination system, after its design and installation, simple brightness level measurements must be taken. For a threedimensional evaluation of the brightness level in indoor spaces in a speedy and accurate manner, the obtained brightness level measurement results and artificial neural network model were used. Upon estimation of the most suitable brightness level for indoor spaces by using the artificial neutral network model, the energy demands required by the illumination elements decreased. Consequently, in this study, with estimations of brightness levels, the extent to which the artificial neutral networks become successful was observed and more correct results have been obtained in terms of both economy and usage.

Investigation Efficiency and Microcontroller-Based Energy Flow Control for Wind-Solar-Fuel Cell Hybrid Energy Generation System with Battery Storage:

In this proposal, microcontroller-based energy flow control was designed in order to effectively and efficiently enable the use of energy sources in a hybrid energy generation system including wind, solar, and hydrogen energy. It was assumed that the hybrid energy generation system is dynamic during the design of the microcontroller-based energy flow control. A wind–solar energy generation system was determined as the base load power plant. Depending on the demand, the battery group and fuel cell were activated effectively. If an energy surplus occurred, it was stored in battery groups and transformed into hydrogen energy via a hydrogen generator simultaneously. In addition to providing energy sustainability, a constant active status of the energy storage group was prevented and the physical life of the group was prolonged by means of the microcontroller-based control system. If consumer demand could not be met by the main energy sources including wind and solar energy, the battery groups and fuel cell were activated and provided the energy sustainability. After a certain level of charge was reached in the battery group, it was deactivated via the control system in order to prevent unnecessary use of energy. By means of the microcontroller-based control system, the usage of energy generated with the hybrid energy generation system was analysed according to its efficiency.

DC grid connected energy flow control formed by three different solar panels, fuel cell and battery-backed hybrid energy generation system

Hybrid energy generation systems help to increase system reliability and improve power quality. However, they come across some challenges in their widespread using area. These problems are intermittently varying renewable energy sources like solar radiation, high installation costs and limited lifetime of energy storage devices. Thus, there is a need to integrate these sources by means of a suitable power management strategy despite the fluctuations in source and load power. In this paper, an energy system comprising two energy sources, namely PV and fuel cells, is proposed. Each of the energy sources is controlled so as to deliver energy at optimum efficiency. The main aim is to give uninterrupted, efficient and economical energy to consumer. So Arduino microcontroller-based control is applied for energy flow control to DC voltage bus. Also, a complete description of the management system is presented.

The extensible analogy for supporting the aspects of smart cities: Demander and supplier

The smart city is still an emerging concept due to the certain and complex requirements of individuals and community. However, there is an agreement among people that ICT will have a critical role in the sense, analysis, and integration of services in smart cities. Several models, simulations and theories have been proposed to facilitate the life of people and community in smart cities. This paper simulates a smart city to deal with the complex and certain requirements of people in smart cities in the foreseeable future.

Analysing of Harmonics Affecting the Energy Quality in Opium Alkaloids Plant's Power System

The quality of energy has been defined to control harmonics caused by non-linear loads and international standards were brought to overcome the harmonic related problems. In determining the power quality, parameters like current-voltage harmonic, transient, flicker, current and voltage imbalance between phases, K factor are examined according to these international standards. The biggest disadvantage of harmonics is that they do not affect the power quality over an individual network but also affect the entire energy system primarily neighbouring facilities. Therefore, the energy system of Opium Alkaloids Plant was examined by using measurements information of current and voltage harmonics affecting the energy quality. And, it has been determined that the harmonics have a negative impact on energy quality. According to these findings, it has been proposed to install a well-designed filter for elimination of harmonics. Besides, it has been emphasised that new hardwares and devices should be chosen to support this harmonic filtering system in the future. KEywORdS Capacitor, Energy Quality, Harmonics, Power Systems, Reactive Power