Modeling of Electric Vehicles as A Load of the Distribution Grid

Electric vehicles (EVs) are expected to reduce carbon emissions from transportation. For this reason, many vehicle manufacturers, countries and international organizations develop their energy and transportation policies in this direction and also support them with practices. As a result of the policies implemented and developments in battery technologies, serious increases are expected in the sales of the EV sector. However, there should be sufficient charging stations for EV charging. The increase in charging stations is expected to cause some positive and negative effects on the grid. In order for electric vehicles to be more acceptable in terms of power systems, it is necessary to understand what kind of electrical character they show. In this article, EV electrical modeling is performed over a charging period by Monte Carlo Simulation using the actual charging data of some EV models charged in a single phase 7, 2 kW-240 V charger. The generated probabilistic model was validated by comparing it with real data. Thus, a reliable modeling has been presented for EV, which is a new load in power systems

Minimum switching number and optimal reactive power choice in reactive power control relay

Reaktif güç kompanzasyonu, genellikle, şebekeye paralel bağlı sabit kondansatörlerin, reaktif güç kontrol rölesi ile, otomatik olarak devreye alınıp çıkarılmasıyla yapılır. Bu çalışmada, kondansatörlerin devreye alınıp çıkarılmalarını optimal olarak gerçekleştiren yeni bir yöntem verilmiştir. Bu yöntemde kondansatörlerin devreye alınıp çıkarılmaları sırasında, deşarj için gerekli gecikme süresi sıfırlanmış ve kondansatörlerin devreye alınıp çıkarılmaları tek tek yerine 1, 2 veya 3’lü gruplar halinde gerçekleştirilir hale gelmiştir. Böylece, kondansatörlerin devreye alınıp çıkarılmaları sırasında, kontaktörlerin anahtarlama sayısı minimum yapılmış, şebekenin daha az indüktif akımla yüklenmesi sağlanmış ve kayıplar azaltılmıştır. Ayrıca, aşırı kompanzasyon ve bunun meydana getireceği istenmeyen olaylar önlenmiştir. Bu röle, imal edilmiş ve deneylerle uygunluğu kanıtlanmıştır.  Anahtar Kelimeler: Kompanzasyon, reaktif güç kontrol rölesi, kondansatör.In an ideal ac power system, the voltage and frequency at every supply point would be constant and free from harmonics, and the power factor would be unity. The simplest way to solve low power factor problems is by adding capasitors to the electrical network. Power factor controllers are used for measuring and controlling the power factor control. In this study, a new approach and method are developed, for reactive power controller. The designed controller, measures, the power factor of the system and it optimally determines the switching patterns of the capasitor banks, which brings the measured power factor to the desired power factor setting. The controller, reduce switching number of contactor and provides less energy losses in the system. For this purpose, firstly, Delay time for capasitor, which is necessary to discharge, was zeroing by using a new method. Secondly, switching program of controller is widely chosen according to the plant condition. In classical relay, only 1 capasitor group can be added or extracted to the bus bar. But in designing new relay, 1, 2, or 3 capasitor banks, which are nearest value, for desired inductive reactive power, can be optimally chosen. Thus, switching number, which is necessary for the capasitor bank during addition or extraction is reduced to a minimum value, and Line is loaded to a less inductive current, so that power losses were reduced to a minimum value, and overcompensation was prevented. This relay is manufactured and approved.Keywords: Compensation, reactive power control relay, capasitor

A tutorial and an application of SM130 RFID Module and Mifare contactless smart memory card

In this study, we have developed a driving circuit based on a PIC 18F4520 microcontroller to control overall operation of an RFID tagging system. Our system utilizes a SonMicro SM130 RFID transmitter/receiver module in order to read manufacturing ID of a Mifare 1K contactless smart memory card. An RF antenna is used to perform data communication between the module and the tag. A graphical LCD is utilized to prompt messages to the user as well as display information received from the module. Our system successfully worked and manufacturing ID of the Mifare 1K memory card was displayed on the screen of the graphical LCDBu çalışmada bir RFID barkod sisteminin çalışmasını kontrol etmek üzere PIC 18F4520 kullanılarak bir sürücü devresi tasarlanmıştır. Sistemimiz SonMicro SM130 RFID alıcı/verici modülünü kullanarak bir Mifare 1K temassız akıllı RFID barkodunun fabrika seri numarasını okuyarak ekranda göstermektedir. Alıcı/verici modülü ile barkod arasında veri alışverişini sağlamak için bir RF anten kullanılmıştır. Kullanıcıya yönelik mesajlar ve barkoddan okunan bilgilerin gösterimi için bir adet grafik LCD kullanılmıştır. Geliştirmiş olduğumuz sistem başarılı bir şekilde çalışmış ve Mifare 1K RFID barkodunun fabrika seri numarası okunarak grafik LCD ekranında gösterilmiştir

A transistor based fast driving circuit for bipolar step motor driving

This work involves developing a transistor based driving circuit for a bipolar step motor. TIP41 and TIP42 transistors are used to construct the driving circuit. The control circuit is constructed based on PIC 18F452 microcontroller. The overall system is first tested in simulation using Proteus program and then implemented experimentally on the breadboard. Experimental results showed that the driving circuit successfully runs the bipolar step motor in both directions and at various speeds.Bu çalışma bipolar adım motorları için transistör tabanlı ve hızlı bir sürücü devre tasarımı geliştirilmesi aşamalarını içermektedir. Sürücü devresi TIP41C ve TIP42C transistörleri kullanılarak geliştirilmiştir. Kontrol devresi PIC 18F452 mikrodenetleyicisi kullanılarak gerçeklenmiştir. Sistemin tamamı önce bilgisayar ortamında Proteus programı kullanılarak simule edilmiş daha sonra ise bord üzerinde kurularak gerçeklenmiştir. Deneysel sonuçlar sürücü devresinin biplar adım motorunu her iki yönde ve farklı hızlarda başarılı bir şekilde çalıştırdığını göstermiştir

A NEW RELAY DESIGN FOR REACTIVE POWER COMPENSATION AND ECONOMICAL COMPARISION WITH CLASSICAL RELAY

In most cases, reactive power compensation is otomatically achieved with reactive power control relay by switching on and off, stationary shunt capasitors to the electrical network. İn this study , a new relay has been designed and developed. İn this method, capasitors which is switched on and of are optimally choosen. İn classical relay , only one capasitor can be added or extructed to the network. But,in designing new relay, 1,2 or 3 capasitor banks which are nearest value for desired inductive reactive power can be optimally choosen. As a result , switching number of capacitor and contactor is reduced minimum value and line is loaded less inductive current , it means that less active power losses. New designed relay has been compared with classical one economically . This relay has been manufactured and approved experimantally

Optimal bidding in Turkey day ahead electricity market for wind energy and pumped storage hydro power plant

In electrical grid; when the demand power increases energy prices increase, when the demand decreases energy prices decrease. For this reason; to increase the total daily income, it is required to shift generations to the hours that high demand power values occurred. Wind Power Plants (WPP) have unstable and uncontrollable generation characteristic. For this reason, energy storage systems are needed to shift the generations of WPPs in time scale. In this study, four wind power plants (WPP) which are tied to the Turkish interconnected grid and a pumped hydro storage power plant (PSPP) that meets the energy storage requirement of these power plants are investigated in Turkey day ahead energy market. An optimization algorithm is developed using linear programming technique to maximize the day ahead market bids of these plants which are going to generate power together. When incomes and generations of the plants that are operated with optimization strategy is analyzed, it is seen that annual income increased by 2.737% compared with WPPs ‘s alone operation and generations are substantially shifted to the high demand power occurred hours.</span

The Level of Power Quality Measurement and Evaluation in A Stone Crusher Plant

Both electric utilities and end users of electric power are becoming increasingly concerned about the quality of electric power. Quality of electrical energy in the electrical system that is requested continuous power (uninterrupted power), constant frequency and with constant amplitude can be explained by sinusoidal voltage. Deformation of voltage in the form of sinusoidal waveform is explained as a harmonic. Harmonics are most important factors in decreasing quality of energy in the electrical system. In industrial plants, existence of harmocins and voltage drop, causes serious problems both in plant and network. This problem affects the cost. In this study, a power quality measurements are carried out in stone crusher plant. Harmonics and voltage drop has been measured and evaluated with the power analyzer. In the power quality measurements, harmonic level of the plant is not so bad. However, it is recommended that compensation system with harmonic elimination can be established in plant

A tutorial and an application of SM130 RFID Module and Mifare contactless smart memory card

In this study, we have developed a driving circuit based on a PIC 18F4520 microcontroller to control overall operation of an RFID tagging system. Our system utilizes a SonMicro SM130 RFID transmitter/receiver module in order to read manufacturing ID of a Mifare 1K contactless smart memory card. An RF antenna is used to perform data communication between the module and the tag. A graphical LCD is utilized to prompt messages to the user as well as display information received from the module. Our system successfully worked and manufacturing ID of the Mifare 1K memory card was displayed on the screen of the graphical LCDBu çalışmada bir RFID barkod sisteminin çalışmasını kontrol etmek üzere PIC 18F4520 kullanılarak bir sürücü devresi tasarlanmıştır. Sistemimiz SonMicro SM130 RFID alıcı/verici modülünü kullanarak bir Mifare 1K temassız akıllı RFID barkodunun fabrika seri numarasını okuyarak ekranda göstermektedir. Alıcı/verici modülü ile barkod arasında veri alışverişini sağlamak için bir RF anten kullanılmıştır. Kullanıcıya yönelik mesajlar ve barkoddan okunan bilgilerin gösterimi için bir adet grafik LCD kullanılmıştır. Geliştirmiş olduğumuz sistem başarılı bir şekilde çalışmış ve Mifare 1K RFID barkodunun fabrika seri numarası okunarak grafik LCD ekranında gösterilmiştir

A Day-Ahead Wind Power Scenario Generation, Reduction, and Quality Test Tool

During the last decades, thanks to supportive policies of countries and a decrease in installation costs, total installed capacity of wind power has increased rapidly all around the world. The uncertain and variable nature of wind power has been a problem for transmission system operators and wind power plant owners. To solve this problem, numerous wind power forecast systems have been developed. Unfortunately none of them can obtain absolutely accurate forecasts yet. Thus, researchers assumed that wind power generation is a stochastic process and they proposed a stochastic programming approach to solve problems arising from the uncertainty of wind power. It is well known that representing stochastic process by possible scenarios is a major issue in the stochastic programming approach. Large numbers of scenarios can represent a stochastic process accurately, but it is not easy to solve a stochastic problem that contains a large number of scenarios. For this reason scenario reduction methods have been introduced. Finally, the quality of this reduced scenario set must be at an acceptable level to use them in calculations. All of these reasons have encouraged authors to develop a wind power scenario tool that can generate and reduce the scenario set and test the quality of it. The developed tool uses historical data to model wind forecast errors. Scenarios are generated around 24 day-ahead point wind power forecasts. A fast forward reduction algorithm is used to reduce the scenario set. Two metrics are proposed to assess the quality of the reduced scenario set. Site measurements are used to test the developed wind power scenario tool. Results showed that the tool can generate and reduce the scenario set successfully and the proposed metrics are useful to assess the quality