Konut binalarındaki kurulu kapasite fazlası ve yenilenebilir enerji kaynaklarının entegrasyonu ile dinamik yük yönetiminin şarj istasyonu boyutlandırılmasına etkileri
Efects of dynamic load management on sizing of charging operations with the integration of surplus installed capacity in residential building and renewable energy
Yazar: ÖZCAN AKBIYIK
Danışman: PROF. DR. ÖNDER GÜLER
İstanbul Teknik Üniversitesi / Lisansüstü Eğitim Enstitüsü / Enerji Bilim ve Teknoloji Ana Bilim Dalı / Enerji Bilim ve Teknoloji Bilim Dalı
Derece: Yüksek Lisans, 2024
Konu: Enerji = Energy

Özet:
Artan nüfusa ve teknolojik gelişmelere bağlı olarak araç sayısı da artmaktadır. Araçlarda kullanılan konvansiyonel yakıt türlerinin ithal olması ve çevresel kaygılardan dolayı da son yıllarda artan araç sayısının önemli bir kısmı geleneksel içten yanmalı motorlu araçların yerine elektrikli araçlar ile karşılanmaya başlanmıştır. Elektrikli araçların (EV) kullanımının çevreye verilen zararı azaltması ve hava kalitesini iyileştirmesi beklenmektedir. Ancak elektrikli araçların yaygınlaşmasıyla birlikte bazı zorluklar da ortaya çıkmıştır. Bu zorluklardan biri de şarj istasyonu altyapısı sorunudur. Bu nedenle şarj istasyonlarının yönetimi çok önemli hale gelmiştir. Ancak EV şarjına yönelik altyapı, park tesislerinin konumu ve kullanılan şarj modelleri gibi faktörlere bağlı olarak değişiklik gösterebilmektedir. Üstelik bu altyapıların etkin yönetiminin olmayışı, elektrikli araçların elektrik şebekesinden düzensiz bir şekilde şarj edilmesiyle birleştiğinde yeni zorluklar ortaya çıkmaktadır. 
Elektrikli araçlara yönelik hızla artan talep, şebeke üzerindeki yükü artırmakta ve yerel ağlarda aşırı yüklenmelere neden olabilmektedir. Bu durum, EV'lerin aynı anda yoğun şekilde şarj edilmesi durumunda ağ kesintileri veya gerilim düşmesi gibi sorunlara yol açmaktadır. Şarj istasyonlarındaki yük yönetimi bu tür sorunların önlenmesine yardımcı olmaktadır. Şarj istasyonunu yönetimi statik ve dinamik yük yönetimi gibi iki farklı şekilde gerçekleştirilebilir. Statik yük yönetimi istasyondaki duruma göre gelen enerjiyi eşit olarak paylaştırır. Herhangi bir akıllı yönetim söz konusu değildir. Dinamik yük yönetimi, şarj istasyonlarının anlık enerji talebini izler ve şarj hızını ağ durumuna göre otomatik olarak ayarlar. Böylece şarj istasyonları ağın anlık ihtiyaçlarına göre esnek olur ve ağın kararlılığını korur. Dinamik yük yönetimi, statik yük yönetiminde farklı olarak, elektrikli araçların şarj sürecini optimize ederek enerji verimliliğini artırır ve şebeke üzerindeki yükü dengeler. 
Bu tezin amacı dinamik yük yönetimiyle statik yük yönetiminin karşılaştırmalı olarak incelenmesidir. Bu inceleme yapılırken, literatürdeki diğer araştırmalara ek olarak, dinamik yük yönetimine bina kurulu gücü ve yenilenebilir enerji entegre edilmiştir. Bu sayede bütünleşmiş sistemlerin dinamik yük yönetiminde nasıl bir etkisi olacağı çalışılmıştır. Statik yük yönetimi akıllı bir sistem olmadığından şebekedeki gücü eşit olarak şarj istasyonuna gelen araçlara pay etmektedir. Dinamik yük yönetiminde ise bu durum, şarj istasyonundaki araç sayısına, ihtiyaç olan enerjiye vs. göre değişmektedir. Bataryası %80 dolan aracın şarj istasyonundan ayrılabileceği öngörülmüştür. Bu çalışmada 3 senaryo ele alınmıştır. 1. durumda araç sayısının daha az olduğu, 2. durumda araç sayısının daha fazla olduğu ve 3. durumda ise 4 saatlik aralıklarla değişen araç sayısına göre incelemiştir. Bu 3 durum 5 ayrı senaryoda ele alınmıştır. Her bir durum da statik yük yönetimi, dinamik yük yönetimi, bina kurulu gücü entegreli dinamik yük yönetimi, yenilenebilir enerji entegreli dinamik yük yönetimi ve hem bina kurulu gücü hem yenilenebilir enerji entegreli dinamik yük yönetimi senaryolarıyla beraber analiz edilmiştir. Çalışmada örnek alınan bina entegrasyonu, 5 bloktan oluşan 10 daireli bir site olup, bu kurulu güç 27,86 kW olarak hesaplanmıştır. Bununla beraber şebekeye olan bağlılığın azaldığı gözlemlenmiştir. Yenilenebilir enerji entegrasyonunda ise, fotovoltaik kurulu gücü ortalama 100 kW ele alınmıştır. Bu değerlendirmelerin sonucunda olasılıksal olarak, şarj istasyonundaki soket sayılarının değişimi gözlemlenmiştir. Örneğin, durum 1' de statik yük yönetimi senaryosunda olasılıksal olarak 10 ila 11 soket yeterli iken dinamik yük yönetiminde soket sayısının 8 ila 9'a düştüğü görülmüştür. Bina entegrasyonu senaryosunda ise 8 soket bulunma olasılığı en yüksektir. Bina entegrasyonu ve yenilenebilir enerji entegrasyonuyla beraber dinamik yük yönetiminde şarj istasyonundaki soket sayısı kullanımının daha düşük olduğu olasılıklar daha yüksektir.

Abstract:
Electric vehicles offer a promising solution to alleviate  problem by serving as an alternative to traditional internal combustion engine vehicles. EVs and alternative fuel vehicles have the potential to reduce the environmental damage caused by fossil fuel vehicles. Compared to traditional internal combustion engines, EVs significantly reduce carbon dioxide emissions and improve local air quality. They also reduce noise pollution caused by fossil fuel vehicles and improve urban quality of life. However, there are some challenges for EVs and alternative fuel vehicles, such as infrastructure and cost. However, with the development of technology and increasing demand, the use of these vehicles is becoming more widespread. 
The electric vehicle market has been growing rapidly and gaining significant momentum in recent years. Demand for environmentally friendly transportation solutions is increasing worldwide, while government environmental protection policies and incentives are contributing to the widespread adoption of electric vehicles. Electric vehicle manufacturers are leading the way in diversifying the market by developing innovative technologies and offering more various models. After all, there are some challenges to further market adoption of electric vehicles, such as expanding charging infrastructure and improving battery technology. With increasing awareness and demand, the market share of electric vehicles is rising day by day and gaining an important place in the automotive industry. In Turkey, the electric vehicle market has shown significant growth and development in recent years. With increasing environmental awareness and sustainability-oriented policies in the country, the interest and demand for electric vehicles is also increasing. Although Turkey has the potential to become a major player in the EV sector, there are still some challenges to the development of the market. These challenges include factors such as inadequate charging infrastructure, high purchase costs of EVs and tax regulations. In addition to this, with the government's incentive policies and domestic production initiatives promoting the use of EVs, the EV market in Turkey is projected to grow further in the future. Accordingly, the interest and investments of domestic manufacturers and international brands in the Turkish EV market are increasing. In the future, EVs and alternative fuel vehicles can become an important part of a sustainable transportation system and are expected to minimize negative impacts on the environment.
With the increasing popularity of electric vehicles, there has been a significant increase in the number of charging stations. This encourages the adoption and use of EVs. The increase in charging stations also supports the growth of the EV market. This is because more charging stations encourage people to buy electric vehicles, while more electric vehicles ensure that charging stations are economically sustainable. Therefore, the increase in EVs and the spread of charging stations create a cycle that triggers and supports each other, contributing to the future of sustainable transportation.
Charging stations for EVs generally come in three main types: AC charging stations, DC fast charging stations and home charging stations. AC charging stations are designed for use in homes or workplaces and can be used directly by the vehicle's internal charger. These stations typically provide 7-22 kW of power and can take several hours to fully charge a vehicle. DC fast charging stations offer fast charging on the road and are usually located along highways and major roads. They provide high-power DC current directly to the vehicle and can charge a vehicle's battery up to 80% in about 30 minutes. Besides, DC fast charging stations are generally more expensive and require more space than AC charging stations. Home charging stations are specially designed stations that allow homeowners to charge their electric vehicles at home. These stations are connected to the home's electrical system and usually have similar power levels to AC charging stations. Each type of charging station offers different advantages depending on the use case, charging speed and charging needs.
These fast and slow charging options provide flexibility according to the needs of EV users and enable different strategies for energy management. Fast charging stations provide a quick energy supply for long journeys or emergencies, while slow charging is more economical and ideal for home use. This diversity facilitates the adoption of electric vehicles by a wider range of users. Nevertheless, energy management at charging stations is becoming increasingly important today.  Different techniques are used in charging station management and one of them is static load management. Static load management is a traditional approach and is not considered as a smart method. Static load management offers less flexibility and is difficult to respond to changes in demand as it operates at constant power consumption. Static load management leads to efficiency issues at charging stations due to its inability to adapt to fluctuations in energy demand. Since this method operates on a set fixed capacity, it cannot respond quickly to increases or decreases in demand. This prevents the efficient use of energy resources and reduces energy efficiency. In the face of technological developments and increasing energy demand, charging stations need more flexible and intelligent management strategies. In addition to static load management, dynamic load management is another form of charging station management. With dynamic load management, control is realized more intelligently and the power at the socket end of the charging station changes dynamically. Dynamic load management increases adaptability and user flexibility. Smart meters enable the withdrawal of excess electricity from buildings and renewable energy. The amount of static and dynamic load management affects how large EV charging stations should be. Static management is typically limited to a set capacity, but dynamic management can adapt to changes in demand more quickly and effectively. Therefore, a more adaptive and efficient system is possible when dynamic load management is chosen for charging station sizing and capacity determination. On the other hand, dynamic load management enables charging sockets to be used more efficiently, increasing energy efficiency and preventing overloading. This results in a more balanced use of energy resources at charging stations and faster and more reliable charging of electric vehicles.
This study aims to contribute to the development of strategies for the management of electric vehicle charging stations to balance the increasing energy demand and reduce the load on the grid with the widespread use of electric vehicles. In this context, this thesis supports the widespread use of electric vehicles and emphasizes the importance of load management in charging stations by providing recommendations for static and dynamic load management of charging stations. In addition to the comparison of static and dynamic load method, it is aimed to expand the objectives of the study with building integration and renewable energy support dynamic load method. On the other hand, the effects of building integration and renewable energy on the number of sockets are also shown. Vehicles arriving at the charging station were analyzed in 3 scenarios. The presence of vehicles at the station was observed based on probability. In the first case the probability of a vehicle arriving is higher than in the second scenario, but in the first case the probability of three vehicles at the station is almost zero, while in the second scenario the probability of three vehicles is 10%. The probability of having no vehicles at the station is also added, which is 30% in the first two cases. In the second case, it was planned to increase the number of vehicles in the station with the possibility of two and three vehicles. With these changing probabilities, we wanted to observe how the charging station would behave according to the number of vehicles. In the third case, completely different from the first two cases, the arrival probabilities of the vehicles at the charging station were determined in four-hour intervals. For example, the probability of there being no vehicles at the charging station between 12:00 and 03:59 at night was taken as 60%, because in the evening, vehicles are parked and charged at the charging station and vehicles with 80% full battery leave the station. If the power of electrical appliances, lighting, sockets, etc. in buildings is known, the installed capacity can be calculated. In order to determine the simultaneous load of an apartment, it must be multiplied by the coefficient of simultaneity. The installed power of a 10-apartment building used in this study is calculated as 27.86 kW with the simultaneity factor. In building integration, the installed power of the building is calculated and then the remaining power is directed to the charging station. This reduces the dependency on the grid. In the renewable energy integration, the power is generated instantaneously and used directly at the charging station, while the average photovoltaic installed capacity in the selected Istanbul location is evaluated as 100 kW. In order to understand these evaluations, the change in the number of sockets in the charging station was observed probabilistically. For example, while 10 to 11 sockets are probabilistically sufficient in static load management, this situation is observed to decrease to 8 to 9 sockets in dynamic load management. By looking at the probabilities of the number of sockets in each scenario, it can be compared how efficient the optimization in the charging station is. The probabilities of the number of sockets show that with dynamic load management, the instantaneous power drawn at the station varies depending on the number of vehicles and the charging station becomes more efficient.