# Research on Renewable Energy Planning Considering the Flexible Region of the Microgrid
## 4 Example Analysis
### Analysis of the Results of the Optimal Allocation of Distributed Energy  
#### 4.2.1 The Optimal Allocation Scheme Considering the Dynamic Boundary  
Distributed energy is allocated considering the fixed boundary and dynamic boundary, respectively, and according to the method mentioned before, we can get the optimal configuration results of the distributed energy and energy storage in Table 2. Table 2 shows the coordinated configuration results of the distributed energy considering the fixed boundary. On the basis of the above input conditions, the wind turbine, photovoltaic generator and energy storage are installed in the IEEE-33 bus standard system. The optimal allocation scheme of DG considering the dynamic boundary is scheme 2, and the other allocation scheme is scheme 1. In the optimal allocation scheme, the wind turbine, photovoltaic generator and energy storage are located at nodes 6, 24 and 31, respectively; in the other allocation scheme, the wind turbine, photovoltaic generator and energy storage are located at nodes 2, 8 and 28, respectively. Under the same configuration capacity, the DGs are installed at different locations in the two schemes, and the comprehensive income of the two schemes is 0.4013 M USD and 0.6716M USD, respectively. Due to the same configuration capacity, the installation cost of DG in the two schemes is the same. However, due to the different operation modes, the operation cost of scheme 1 is obviously higher than that of scheme 2, and the loss of load cost of scheme 1 is also higher than that of scheme 2. 2.2 Power Supply Area Analysis and Comprehensive Benefit Analysis of the Distribution Network Planning Island  
On the basis of the above input conditions, the wind turbine, photovoltaic generator and energy storage are configured in the IEEE-33 bus standard system. When a failure occurs, the microgrid operates considering the fixed boundary in scheme 1, and the dynamic boundary in scheme 2. The results of scheme 1 considering the fixed boundary island division are shown in Figure 2a and the results of scheme 2 considering the dynamic boundary island division are shown in Figure 2b. In the fixed boundary island division, the wind turbine, photovoltaic generator and energy storage are located at nodes 6, 24 and 31, respectively; in the dynamic boundary island division, the wind turbine, photovoltaic generator and energy storage are located at nodes 6, 24 and 31, respectively. The configuration positions of the wind turbine, photovoltaic generator and energy storage considering the fixed boundary are the same as when considering the dynamic boundary. The local consumption of active power to reduce the network loss is considered, therefore the wind/solar/storage should be configured in the node with the concentrated load. The influence of the boundary on the reliability and comprehensive benefits of the system mainly lies in the difference of the load power supply guaranteed by dividing the island when an operation failure occurs. Therefore, in terms of long-term scale, to ensure the comprehensive benefits of the system, the configuration positions of the wind turbine, photovoltaic generator and energy storage should be in the load concentration area, no matter whether they are the fixed boundary island division or the dynamic boundary island division. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Scheme**} & \multicolumn{2}{c}{**Configuration of**} & **Configuration of** & **Configuration of** \\  & & **Wind** & **Photovoltaic** & **Energy Storage** \\ \hline Other allocation & Location & (2, 8, 28) & (2, 8, 28) & (2, 8, 28) \\ scheme (scheme 1) & Capacity/kW & (440, 420, 270) & (220, 840, 540) & (132, 252, 162) \\ The optimal allocation & Location & (6, 24, 31) & (6, 24, 31) & (6, 24, 31) \\ scheme (scheme 2) & Capacity/kW & (440, 420, 270) & (220, 840, 540) & (132, 252, 162) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Optimal allocation scheme of the distributed energy considering the dynamic boundary.