# Assessing the Impact of an EV Battery Swapping Station on the Reliability of Distribution Systems
## 6 Numerical Study
### Results  
In this section, to compare the effect of BSS on the reliability of the distribution network, we assigned three cases:  
1. Case-1: The distribution network does not have a BSS, and all electrical power is provided by the external grid. When the grid fails, the system has no backup power source. 2. Case-2: The distribution network is equipped with a BSS, but it does not have the capability of V2G. It is equivalent to increase the load on the distribution network. 3. Case-3: The distribution network is equipped with a BSS and has the capability of V2G. In the event of a grid failure, BSS can be used as a backup power source to supply power back to the distribution network. In order to quantify the effect of BSS on the reliability of the distribution network, we use SAIFL, SAIDI, and SEENS as system reliability indexes, and LAIFI, LAIDI, and LEENS as load point reliability indexes. According to the simulation results, the reliability indexes of the distribution network in the three cases are shown in Tables 4-6. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**System** & \multicolumn{2}{c}{**Load Point**} & **1** & **2** & **3** & **4** & **5** & **6** & **7** & **8** \\ \hline SAIFI (time/c-y) & 0.6157 & LAIFI (time/c-y) & 0.2000 & 0.2000 & 0.2000 & 0.3000 & 1.3000 & 0.8000 & 0.5000 & 1.4000 \\ \hline SAIDI (h/c-y) & 2.3443 & LAIDI (h/c-y) & 0.6000 & 0.6000 & 0.6000 & 0.7000 & 2.7000 & 4.6000 & 1.1000 & 4.8000 \\ \hline SEENS (MWh/y) & 28.7209 & LEENS (MWh/y) & 0.2214 & 0.1992 & 0.2656 & 0.1414 & 0.6028 & 3.0214 & 0.8242 & 0.9343 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Calculation of system reliability indexes in Case 1. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline Rated charging power (kW) & 9 \\ Rated discharging power (kW) & 4 \\ Batteries efficient & 0.95 \\ Batteries capacity (kWh) & 45 \\ Queue parameters (\(S_{0}\),\(S\)) & (50,80) \\ Electricity price (\$) [13] & 0.5 (peak time) \\  & 0.2 (shoulder peak time) \\  & 0.15 (off peak time) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: BSS parameters applied in the paper. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**System** & **Load Point** & **1** & **2** & **3** & **4** & **5** & **6** & **7** & **8** \\ \hline Load point & 9 & 10 & 11 & 12 & 13 & 14 & 15 & 16 \\ \hline LAIFI & \begin{tabular}{c} 1.3000 \\ (time/c-y) \\ \end{tabular} & 1.3000 & 0.8000 & 0.4000 & 0.5000 & 0.3000 & 1.4000 & 1.2000 & 1.9000 \\ \hline LAIDI & \begin{tabular}{c} 2.1000 \\ (h/c-y) \\ \end{tabular} & 2.1000 & 3.5000 & 3.1000 & 2.0000 & 0.7000 & 3.0000 & 3.9000 & 9.2000 \\ \hline LEENS & \begin{tabular}{c} 0.4645 \\ (MWh/y) \\ \end{tabular} & 0.4645 & 0.4317 & 0.4771 & 0.3173 & 0.3091 & 0.6371 & 0.7806 & 1.7565 \\ \hline Load point & 17 & 18 & 19 & 20 & 21 & 22 & 23 & 24 \\ \hline LAIFI & \begin{tabular}{c} 0.8000 \\ (time/c-y) \\ \end{tabular} & 0.8000 & 0.3000 & 0.6000 & 0.4000 & 0.2000 & 0.2000 & 0.5000 & 0.5000 \\ \hline LAIDI & \begin{tabular}{c} 1.7000 \\ (h/c-y) \\ \end{tabular} & 1.7000 & 0.7000 & 1.8000 & 0.9000 & 0.6000 & 0.6000 & 2.3000 & 2.7000 \\ \hline LEENS & \begin{tabular}{c} 0.6022 \\ (MWh/y) \\ \end{tabular} & 0.6022 & 0.2249 & 0.6362 & 0.3135 & 0.1992 & 0.1992 & 2.8083 & 3.4102 \\ \hline Load point & 25 & 26 & 27 & 28 & 29 & 30 & 31 & 32 \\ \hline LAIFI & \begin{tabular}{c} 1.4000 \\ (time/c-y) \\ \end{tabular} & 1.4000 & 1.6000 & 1.2000 & 0.7000 & 0.6161 & 0.6000 & 0.5000 & 0.2000 \\ \hline LAIDI & \
\begin{tabular}{c} 2.7000 \\ (h/c-y) \\ \end{tabular} & 2.7000 & 5.0000 & 3.1000 & 4.3000 & 1.3881 & 3.6000 & 2.7000 & 0.6000 \\ \hline LEENS &
\begin{tabular}{c} 0.5652 \\ (MWh/y) \\ \end{tabular} & 0.5652 & 1.0695 & 0.5894 & 1.7143 & 0.9947 & 1.7466 & 2.1303 & 0.1328 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: \(Cont.\)