# Multi-Stage Dynamic Transmission Network Expansion Planning Using LSHADE-SPACMA
## 5 Simulation Results and Analyses
### West Delta Network (WDN) System Planning
#### 5.2.3 Multi-Stage Dynamic Planning for WDN up to 2040 with Security N-1 Security Constraint  
To study the impact of including N-1 security constraint on WDN planning, two scenarios were suggested to keep the power system reliable, secure, and low cost:  
Scenario 1: The system was planned with the same routes proposed in [PERSON] et al. [24] and load shedding was applied. Scenario 2: The maximum number of circuits in each route was supposed to be four, as per Egyptian requirements. Table 8 and Figure 5 show that the planning of WDN with routes proposed by [PERSON] et al. [24] for scenario 1 cannot ensure system security without load shedding. Scenario 1 results in the addition of 15 circuits with load shedding of 162.68 MW in the first stage, 6 circuits with load shedding of 43.23 MW in the second stage, 1 circuit with load shedding of 127.4 MW in the third stage, 4 circuits with load shedding of 134.19 MW in the fourth stage, and 5 circuits with load shedding of 160.46 MW in the fifth stage. The total investment cost would be 287.46 million USD. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Year** & **Predicted Load** & **Year** & **Predicted Load** \\ \hline
2016 & 1260.2 & 2029 & 2128.3 \\
2017 & 1325.1 & 2030 & 2195.8 \\
2018 & 1390.6 & 2031 & 2263.4 \\
2019 & 1456.6 & 2032 & 2330.9 \\
2020 & 1523 & 2033 & 2398.5 \\
2021 & 1589.7 & 2034 & 2466.1 \\
2022 & 1656.7 & 2035 & 2533.7 \\
2023 & 1723.8 & 2036 & 2601.3 \\
2024 & 1791 & 2037 & 2668.9 \\
2025 & 1858.4 & 2038 & 2736.5 \\
2026 & 1925.8 & 2039 & 2804.1 \\
2027 & 1993.2 & 2040 & 2871.7 \\
2028 & 2060.7 & 2040 & 2871.7 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Load forecasting for WDN using ANFIS technique up to year 2040. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Stage No. **} & \multicolumn{8}{c}{**Added Lines**} & \multicolumn{8}{c}{**Total Cost**} \\  & **5–6** & **5–8** & **6–34** & **7-34** & **7-36** & **23–53** & **22–53** & **32–53** & **3–53** & **34–53** & **36–53** & **8–53** & **(Million USD)** \\ \hline
**1** & 0 & 0 & 3* & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 0 & **4.71** \\
**2** & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & **1** & 0 & **7.23** \\
**3** & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 2 & 1 & 2 & 0 & 3.42 \\
**4** & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 2 & 2 & 2 & 0 & 6.28 \\
**5** & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 2 & 2 & 2 & 2 & 6.58 \\ \hline \hline \endScenario 2 proposes 25 circuits in the first stage, 8 circuits in the second stage, 20 circuits in the third stage, 7 circuits in the fourth stage, and 12 circuits in the fifth stage, as depicted in Table 8 and Figure 6. The total investment cost is 57.33 million USD, lower than scenario 1. Hence, scenario 2 is recommended. It is clear that steady-state power system insecurity based on scenario 1 overloads transmission lines and causes successive interruptions leading to partial blackouts (Figure 7 and Table 8). The results demonstrate that increasing the capacity at bus 53 cannot mitigate the rolling blackout problem, and the available solution is to install distribution generators at various locations, causing the total investment cost to increase. On the other hand, MSDTNEP of WDN based on scenario 2 leads to a better plan for WDN and lower investment cost, because it accounts for several features such as annual load growth, prevention of rolling blackouts, and N-1 security criterion. Blackouts are avoided in scenario 2 by installing additional circuits of lower cost compared to the cost of installing new distribution generators (Figure 7). \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{3}{*}{**Candidate**} & \multicolumn{4}{c}{**Scenario 1**} & \multicolumn{4}{c}{**Scenario 2**} \\ \cline{2-11}  & \multicolumn{4}{c}{**Stage Number**} & \multicolumn{4}{c}{**Candidate**} & \multicolumn{4}{c}{**Stage Number**} \\ \cline{2-11}  & **1** & **2** & **3** & **4** & **5** & **1** & **2** & **3** & **4** & **5** \\ \hline
5  
Figure 5: Optimal configuration for WDN based on scenario 1.