Elbilens påverkan på elnätet vid hemmaladdning och tekniker för effekttoppsreduktion : En fallstudie på två av Sala-Heby Energis lågspänningsnät

Sammanfattning: In order to reach climate goals regarding the reduction ofcarbon dioxide in the environment, the decarbonisation of the transport sector plays a crucial role. Along with this revolution, electric vehicles will most likely be a candidate to replace market shares from gasoline and diesel. The deployment of electric cars is now starting to increase, by over 2 millions electrical vehicles running on the streets world wide in year 2016, which is more than the double compared to previous year. This master thesis examines home charging and its impact on the distribution grid of two types, one in a smaller urban area and one in a rural area in the Swedish city Sala. Different integration levels of electric vehicles are examined regarding voltage drop, relative loading of conductors and transformers, and the voltage symmetry with charging only on one phase. The simulations are made in the NIS-based system dpPower based on charging data from Grahn et.al.(2013), and the study of powerpeaks is made in Matlab with the use of consumption data from customers. The results show that the transfomer is the only limitation in the grid of the urban area, which fails at an integration level of 50 percent at 11 kW of charging. Compared to the grid in the rural area which reacts more strongly of home charging. In this case it is most likely to fail at 30 percents integration at 3,7 kW of charging. Also a greater accuracy has to be taken into account here regarding the placing of one phase-chargers at different phases. This in order to not exceed the 2 percent limit of voltage symmetry. With the aim to reduce power peaks, the grid seems to benefit from high demand response and local battery storage, which reduce the power peaks to an extent that could be comparable to reducing the integration level of electric vehicles from 50 to 30 percent.