# Impact of the Integration of the Electric Vehicle on Low-Voltage Rural Networks
## 5 Improvements to the Charging Procedures
### Scenario 3: Connection of Specific Power Electronics to Reduce Voltage and Current Unbalance
The active power exchange is limited to 10 kW in phases A and C during the time interval in which the maximum EV charging current occurs. In this case, the active power exchange has been prioritised; therefore, if the current limit is reached, the active power exchange will be prioritised, and the reactive power exchange will be reduced, as observed between 19:15 and 21:15. This affects the active and reactive power per phase upstream of the D-STATCOM equipment, as shown in Figure 9c,d. When the current limitation is active, the active power through the different phases is different, and the reactive power is different from zero. \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline  & \begin{tabular}{c} **Total** \\ **Losses** \\ **(kWh/Day)** \\ \end{tabular} & \begin{tabular}{c} **Minimum** \\ **Voltage** \\ **(pu)** \\ \end{tabular} & \begin{tabular}{c} **Max. Neutral** \\ **Current** \\ **(Au)** \\ \end{tabular} & \begin{tabular}{c} **Max.** \\ **Loading** \\ **(\%)** \\ \end{tabular} & \begin{tabular}{c} **CUF** \\ **(\%)** \\ \end{tabular} & \begin{tabular}{c} **CUF** \\ **(\%)** \\ \end{tabular} & \
\begin{tabular}{c} **CUF** \\ **(\%)** \\ \end{tabular} &
\begin{tabular}{c} **CUF** \\ **(\%)** \\ \end{tabular} \\ \hline Scenario 1 & 18.91 & 0.838 & 152.1 & 85.06 & 39.97 & 54.9 & 2.64 & 3.65 \\ Position 1 & 15.85 & 0.876 & 96.2 & 73.54 & 36.81 & 51.2 & 1.75 & 2.40 \\ Position 2 & 14.86 & 0.878 & 87.5 & 72.58 & 17.66 & 26.0 & 1.43 & 2.11 \\ Position 3 & 15.23 & 0.877 & 112.3 & 72.55 & 16.89 & 25.0 & 1.45 & 2.14 \\ Position 4 & 15.45 & 0.877 & 126.1 & 72.56 & 16.20 & 24.1 & 1.45 & 2.14 \\ Position 5 & 15.55 & 0.872 & 138.0 & 72.38 & 16.77 & 25.0 & 1.56 & 2.29 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Comparison of the results depending on the D-STATCOM location. When the limit per phase of the D-STATCOM is reached, no matter what position it is connected, the active power balance and the compensation of reactive power in all phases can not be achieved. Figure 8(a) shows how Phases A and C reach the 10 kW limit, preventing the injection of reactive power during that period, as seen in Figure 8(b), particularly in Phases A and C. Figure 8(c) depicts how this limit impedes the balancing of powers across all three phases, especially in Phase A. Furthermore, during the same period, the reactive power of Phase A and Phase C is not reduced, and in the case of Phase B, it is not completely compensated, as seen in Figure 8(d). It is worth mentioning here that the D-STATCOM system performs balancing at one point of the analyzed network, so the currents will continue to be unbalanced downstream of the connection point. To ascertain whether this solution can address the issues related to the uncontrolled connection and charging of electric vehicles, a series of simulations have been conducted to assess the impact of increasing the nominal power of the D-STATCOM at Position 2. Table 4 and Figure 10 confirm the assumption showing an improvement in the results in terms of voltage, load, and losses when increasing the nominal power of the equipment. Figure 8: Comparison of the results of Scenario 3 with the five different positions for the D-STATCOM regarding Scenario 1. Figure 9: Delivered active and reactive power (**a,b**) and Upstream active and reactive power (**c,d**) in each phase due to the connetion of the 30 kVA D-STATCOM. It is also reflected that above 60 kVA, there is no improvement, and the results stay the same because the current when the rated power is greater than that value is no longer limited. In this case, the minimum voltage remains at 0.902 p.u., just above the 0.9 p.u. limit given by the standards.