# Impact of the Integration of the Electric Vehicle on Low-Voltage Rural Networks
## 3 Methodology
### EV Charging Modes  
The IEC 61851-1 standard [55] establishes four charging modes for electric vehicles. Modes 1, 2, and 3 all involve charging in alternating current, with the charger on board the vehicle, at power levels ranging from 3.7 kW in the first case, up to 44 kW in Mode 3. Mode 4 considers alternating and direct current charging with power levels reaching 240 kW. However, when integrating electric vehicles to the grid, the ability to control the charging process from electric vehicle supply equipment (EVSE) is more important than power limits. This control can be based on directives from the DSO or signals from voltages and currents measured at the charger connection point. Only Modes 3 and 4 allow for controlled charging through directives or load limitation. Communication between EV and EVSE in  
\begin{table}
\begin{tabular}{c c c c c c} \hline
**Circuit** & **Number of Loads** & **Contracted Power** & **Domestic** & **Industrial** & **Service** \\ \hline
1 & 12 & 147.5 & 5 & 2 & 5 \\
2 & 9 & 243.5 & 7 & 0 & 2 \\
3 & 70 & 816.0 & 54 & 2 & 14 \\
4 & 20 & 182.5 & 16 & 1 & 3 \\
5 & 24 & 261.5 & 22 & 0 & 2 \\
6 & 52 & 404.9 & 41 & 0 & 11 \\
7 & 58 & 471.8 & 50 & 5 & 3 \\ \hline \end{tabular}
\end{table}
Table 1: Distribution of the loads in the network circuits.  
Figure 2: **(a)** Power consumed by loads as a function of time of day; **(b)** charging profile of Electric Vehicles (EVs) at slow charging, \(p<3.7\) kW with a zoom into the charging period.  
Europe follows the ISO 15118 protocol [56] for both Mode 3 and the Combined Charging System (CCS) of Mode 4, as well as wireless charging. Intelligent charging applications calculate personalized charging schedules based on grid conditions, energy requirements, and driver mobility schedules. This ensures each charging session is optimally adjusted to the grid's capacity and the electric demand generated by simultaneous electric vehicle charging. Finally, it should also be considered that according to [57], the predominant trend for charging in various studied countries globally occurs after 18:00, peaking around 21:00 when users arrive home.  
According to the IEA's Global Electric Vehicle Outlook 2022 [57], it is projected that by 2030, 90% of EV chargers will be privately owned, ranging in power from 3 to 22 kW. This form of charging is expected to remain dominant, particularly for personal vehicles, with 70% of the total energy dedicated to EV charging derived from private chargers. The proportion of private charging stations will largely hinge on whether EV owners reside in individual homes or larger residential complexes. In Spain, the Business Association for the Development and Promotion of Electric Mobility estimates that 85.9% of EV owners have private chargers installed in their homes [58]. However, it is important to note that the average power contracted by Spanish households stands at 4.2 kW, according to the National Commission for Markets and Competition. This figure dropped to 3.9 kW over the past year for households with contracts in the regulated market [59]. Given the high cost associated with the contracted power term, there is a prevailing trend towards reducing the contracted power level. Consequently, it has been assumed in this study that charging will occur at a lower power rating of 3.7 kW. This decision is primarily driven by the desire to mitigate the need for most users to increase their electricity contract's power term, which would significantly escalate electricity bill expenses. Therefore, the domestic charging stations examined in this study will utilize single-phase chargers with control capabilities (Mode 3), and charging will commence upon the individual's arrival at home.