## 3 Experimental Results
### Results of IEEE 33-Bus System  
The IEEE 33-bus system has 32 lines and 33 buses. In this system, the base voltage is 12.66 kV, and the base power is 100 MVA. The line and load data of this system is given in [33] and the single line diagram is illustrated in Figure 4. In the base case, the power losses are 210.98 kW and 143.14 kVAR, respectively. \(\bullet\)**Scenario I:** Installation of only DGs  
Optimal locations and capacities of DGs at unity p.f are determined with AOA, and the obtained results are given in Table 2. DGs are settled in buses 14, 24, and 30 with capacities of 776.4 kW, 1099.0 kW, and 1070.2 kW, respectively. Thus, the total power loss was reduced from 210.98 kW to 72.79 kW. The lowest power loss is obtained with AOA when the results obtained from the other optimization algorithms are compared. \begin{table}
\begin{tabular}{l l l} \hline
**Scenarios \#** & **Installation Mode** & **Network** \\ \hline Scenario I & Installation of only DGs & IEEE 33-bus network \\ Scenario II & Installation of only CBs & IEEE 33-bus network \\ Scenario III & Installation of DGs and CBs simultaneously & IEEE 33-bus network \\ Scenario IV & Installation of DGs at the optimal p.f & IEEE 33-bus network \\ \hline Scenario I & Installation of only DGs & IEEE 69-bus network \\ Scenario II & Installation of only CBs & IEEE 69-bus network \\ Scenario III & Installation of DGs and CBs simultaneously & IEEE 69-bus network \\ Scenario IV & Installation of DGs at the optimal p.f & IEEE 69-bus network \\ \hline \end{tabular}
\end{table} 
Table 1: Scenarios. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Method**} & \begin{tabular}{c} **Optimal** \\ **Location** \\ **(Bus No.)** \\ \end{tabular} & \begin{tabular}{c} **Optimal** \\ **DG Size** \\ **(MW)** \\ \end{tabular} & \
\begin{tabular}{c} **Power** \\ **Loss** \\ **(kW)** \\ \end{tabular} &
\begin{tabular}{c} **Loss** \\ **Reduction** \\ **(\%)** \\ \end{tabular} \\ \hline \multirow{2}{*}{AM [11]} & 13 & 1.121 & \multirow{2}{*}{89.5} & \multirow{2}{*}{57.28} \\  & 29 & 1.027 & & \\  & 31 & 0.126 & & \\ \hline \multirow{2}{*}{FWA [12]} & 14 & 0.5897 & \multirow{2}{*}{88.68} & \multirow{2}{*}{56.24} \\  & 18 & 0.1895 & & \\  & 32 & 1.0146 & & \\ \hline \multirow{2}{*}{MTLBO [13]} & 23 & 1.066 & \multirow{2}{*}{80.22} & \multirow{2}{*}{62} \\  & 32 & 0.847 & & \\  & 15 & 0.885 & & \\ \hline \multirow{2}{*}{JAYA [13]} & 29 & 0.921 & \multirow{2}{*}{76.66} & \multirow{2}{*}{63.6} \\  & 25 & 0.795 & & \\  & 12 & 1.110 & & \\ \hline \multirow{2}{*}{GWO [13]} & 12 & 0.955 & \multirow{2}{*}{74.10} & \multirow{2}{*}{64.88} \\  & 25 & 0.889 & & \\  & 30 & 1.037 & & \\ \hline \multirow{2}{*}{COA [14]} & 14 & 0.7096 & \multirow{2}{*}{76} & \multirow{2}{*}{63.98} \\  & 25 & 0.5954 & & \\  & 30 & 0.9972 & & \\ \hline \multirow{2}{*}{ECOA [14]} & 14 & 0.7376 & \multirow{2}{*}{74.6} & \multirow{2}{*}{64.64} \\  & 25 & 0.6518 & & \\  & 30 & 1.0705 & & \\ \hline \multirow{2}{*}{SIMBO-Q [15]} & 14 & 0.7638 & \multirow{2}{*}{73.4} & \multirow{2}{*}{65.20} \\  & 24 & 1.0415 & & \\  & 29 & 1.1352 & & \\ \hline \multirow{2}{*}{QOSIMBO-Q [15]} & 14 & 0.7708 & \multirow{2}{*}{72.8} & \multirow{2}{*}{65.48} \\  & 24 & 1.0965 & & \\  & 30 & 1.0655 & & \\ \hline \multirow{2}{*}{AA [16]} & 13 & 0.79 & \multirow{2}{*}{72.89} & \multirow{2}{*}{65.45} \\  & 30 & 1.012 & & \\ \hline \multirow{2}{*}{HHO [17]} & 13 & 0.8173 & \multirow{2}{*}{72.80} & \multirow{2}{*}{65.4956} \\  & 24 & 1.0829 & & \\  & 30 & 1.0465 & & \\ \hline \multirow{2}{*}{SPBO [17]} & 14 & 0.7723 & \multirow{2}{*}{72.79} & \multirow{2}{*}{65.5003} \\  & 24 & 1.1059 & & \\  & 30 & 1.0685 & & \\ \hline \multirow{2}{*}{AOA} & 14 & 0.7764 & \multirow{2}{*}{72.79} & \multirow{2}{*}{65.50} \\  & 24 & 1.0990 & & \\ \hline \end{tabular}
\end{table} 
Table 2: The results of optimum DGs allocation for IEEE 33-bus system. Figure 4: IEEE 33-bus system.