Impact of modelling of MV network and remote loads on estimated harmonic hosting capacity for an EV fast charging station
Naser Nakhodchi, Math Bollen
Abstract
The ability of the distribution network to host electric vehicle (EV) charging might be limited by the harmonic voltages due to their harmonic emission. Network harmonic impedance seen from the point of connection of the charging station plays an important role in harmonic voltage calculation. In this paper, the hosting capacity is estimated for a fast charging station close to a distribution transformer considering different scenarios in terms of network modelling. Data from a typical Swedish distribution network is used, together with a one-month measurement of the emission from state-of-the-art EV charging. The hosting capacity using harmonic voltage limits is compared with the hosting capacity using the transformer rating. A stochastic approach is used for both. This paper shows that harmonic hosting capacity studies are needed; it shows that details of the distribution network must be included to get an accurate estimation of the harmonic hosting capacity; it also shows that a stochastic approach is needed for estimating the harmonic hosting capacity.