## 4 Conclusions  
In this paper, a two-stage method for the swift identification of single and multiple DG location and sizing has been presented. A topological-based method that is non-iterative in nature is suggested for the quick location of DG placement in radial distribution systems. This suggested approach was first applied to a system structure in order to identify suitable locations for placing DGs in an optimal manner to reduce the power losses in the system and enhance the voltage security margin of the system. Particle swarm optimization was employed to determine the sizes of the DGs required to be placed at the identified locations. The suggested approach was applied to the IEEE 33-bus test system to test its applicability and effectiveness. The results obtained show that using the identified locations by the CF ranking method, either single DG or multiple DGs can be optimally \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Method**} & \multirow{2}{*}{**Location (Bus** **Nos.)**} & \multirow{2}{*}{**DG Size (MW)**} & \multirow{2}{*}{**Power Loss with No DG (MW)**} & \multirow{2}{*}{**Power Loss with Multiple**} & \multirow{2}{*}{**Power Loss (\%)**} & \multirow{2}{*}{**Minimum Voltage (pu)**} \\  & & & & & & \\ \hline Lyrf [45] & Bus 18 & 0.743 & & 146.82 & - & - \\ Hybrid & & & & & & \\ analytical- & 6 & 2.707 & - & 99.22 & - & 0.9530 @bus 18 \\ heuristic [46] & & & & & & \\ IA [45] & 6 & 2.601 & 210.98 & 111.11 & - & - \\ EVPSO [49] & 11 & 0.763 & 210.98 & 140.190 & 33.55 & 0.9604 \\ ELF [45] & 6 & 2.601 & 210.98 & 111.11 & - & - \\ DAPSO [49] & 8 & 1.212 & 210.98 & 127.17 & 39.7 & 0.9635 \\ ALO [47] & 6 & 0.850 & 210.98 & 103.05 & 51.15 & 0.9503 @bus 18 \\ VSI-based [48] & 30 & 1.243 & 210.07 & 81.50 & 60.36 & - \\
**This paper** & **Bus 18** & **2.000** & **102.68** & **30.70** & **70.1** & **0.9843 @bus 30** \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Comparison of the results obtained with the existing methods for installing a single DG. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Method**} & \multirow{2}{*}{**Location (Bus** **Nos.)**} & \multirow{2}{*}{**DG Size (MW)**} & \multirow{2}{*}{**Power Loss with No DG (MW)**} & \multirow{2}{*}{**Power Loss with Multiple**} & \multirow{2}{*}{**Power Loss (\%)**} & \multirow{2}{*}{**Min. Voltage**} \\  & & & & & & \\ \hline Hybrid & & & & & & \\ CBGA-VSA [23] & 13, 24, 30 & 2.945 & - & 0.728 & 65.5 & 0.9687 @bus 33 \\ IHHO [24] & 14, 24, 30 & 2.923 & 2.1098 & 0.728 & 65.5 & 0.9790 @bus 18 \\ ALO [47] & 13, 30 & 2.041 & 2.1098 & 0.826 & 60.8 & 0.9732 @bus 33 \\ GA [46] & 30, 13 & 2.190 & - & 0.818 & 62.5 & 0.9734 @bus 33 \\ Hybrid & & & & & & \\ DSCA-SOCP & 13, 24, 30 & 2.945 & 2.1099 & 0.728 & 65.5 & - \\
[50] & & & & & & \\ SPPA [7] & 3, 6 & 3.495 & 2.1099 & 0.637 & 69.4 & 0.9929 @bus 18 \\
**VSI-based**[48] & **30, 25** & 1.492 & 2.1007 & **0.729** & 65.29 & - \\
**This paper** & **18, 33, 32** & **2.640** & **1.0268** & **0.2045** & **80.1** & **0.9960 @bus 28** \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Comparison of the results obtained with the existing methods for multiple DG integration. placed to enhance the voltage profile of a network and minimize network losses. The influence of identifying locations for DG placement with the CF method using both single and multiple DG integration was investigated. It was observed that the voltage profile and power losses of the system were highly influenced by the number of DGs integrated into the system. In other words, as the number of DGs integrated into the system increased, the system voltage profile increased and the power losses were reduced, irrespective of the DG types. However, it is observed, based on the results obtained, that there is a limit to the number of DGs that can be installed in a system depending on the system size. If this number is exceeded, the voltage profile is reduced and network losses increase.