Low Voltage Network Modelling

Abstract

The presence of electrical vehicles and distributed photovoltaic generation in France is constantly increasing in the home building sector. In this study it is seen how these increments of consumption or production affect to a low voltage network. To achieve this objective, a 100 meters long low network has been modelled. It is made up an aerial and three phase line with a section of 70 mm2 of aluminium. This network supplies electricity to a neighbourhood in France with nine houses. Each home can have electrical vehicles or photovoltaic generation or both. For this study three different profiles have been created. One profile is created with the consumption of the nine different houses, another profile is created for the photovoltaic generations and one more profile is created for the electrical vehicles batteries consumption. In order to calculate the yearly consumption and the yearly Joule losses in this low voltage network, simulations with MATLAB have been done. With these simulations the consumption and Joule losses are calculated for different cases. The first case is that where the neighbourhood has any EV or any PV generation and it is compared with the cases where the neighbourhood has EVs or PV generation or both. A sensibility analysis has also been done in order to see the influence of the EVs charging hour. The yearly consumption and the yearly Joule losses have been calculated for five different cases, one case for each of the five different hours: at 8h, at 17h, at 19h, at 21h and at 00h. For each of these cases, all the EVs start charging at the same time until 5,5 kWh every day. This analysis is realized first without photovoltaic generation and then case with photovoltaic generation. Finally, it is seen that photovoltaic generation reduces the average consumption whereas sometimes Joule losses can be increased; it is also proved that PV generation can help to reduce the impact of electrical vehicles if they are charged during the solar hours. Regarding the EVs, the consumption and Joule losses are increased especially when EVs are charged during the existing peak hours; the best way to charge EVs without increasing Joule losses would be to charge the EVs during the off-peak hours.

Outgoing