Analiza wpływu ładowania pojazdów elektrycznych na dynamikę zmian dobowego obciążenia systemu elektroenergetycznego

W artykule dokonano analizy możliwego wpływu ładowania samochodów elektrycznych na dynamikę zmian obciążenia dobowego systemu elektroenergetycznego. Oceniono możliwe zmiany kształt wykresu dobowego, w przypadku gdyby 5% użytkowanych samochodów zastąpić samochodami elektrycznymi. Analizie zostały poddane dwa warianty współpracy samochodów z systemem: G2V (proste ładowanie samochodów) oraz V2G (wykorzystanie możliwości oddawania energii do sieci). W artykule zaprezentowano wpływ samochodów na tzw. gradienty obciążeń, czyli szybkość narastania lub spadku obciążenia na granicach stref czasowych.

---

In this article there were presented an analysis of the impact of charging electric cars on daily load curve of the power system. There were shown three variants of daily load curve – a curve of actual load, curve that takes into account impact of electric cars by G2V scenario and curve that takes into account impact of electric cars by V2G strategy. As part of analysis, there were calculated and presented values of load gradients. Load gradient is a factor that indicates the dynamics of load changes. There were also shown parts of curves, that were analysed. On graphs there were applied trend lines and its equations. Load gradients were calculated in both ways – as a derivative of trend line equation and as the ratio of load increase to the time in which it lasted. Low values of gradients shows that, the increases (or decreases) of power demand were not sudden and proceeded in a sustainable manner. High values of gradients were not desirable, because it means that power demand increases (or decreases)in sudden and quick way in short time. It is easier for power system to cover power demand that not changes suddenly. Depending on the chosen strategy, there were different values of gradients. Based on calculations, the best for power system is V2G variant. V2G solution guarantees a higher demand during night valley and reduction of peak demands. That means power increases from night valley to morning peak and decreases from evening peak to night valley more fluently. This is shown by low gradients values.