## 5 Case Simulation
### Analysis of IEMG Energy Supply Operations  
Using IEMG1 in Scenario 2 as an example, see Appendix A for IEMG2 and IEMG3. The optimal power operation strategy results can be seen in Figure 6, showing that power interaction always exists between IEMG1 and the other IEMGs, mainly as interactive power. From Figure 6, it is observed that from 0:00 to 24:00, its operating output always remains at the utmost, indicating that IEMG's own electrical power can meet its electrical load demand. Also, it signifies the frequent power trade among IEMGs, highlighting the clear cooperation advantage among IEMGs. With the combination of IEMG's benefits, it can be noticed that all three IEMGs have shifted their costs to negative values after cooperation, signifying that IEMG has made profits. In the figure, it can also be seen that renewable energy output within IEMG plays a significant role, stating that the absorption rate of renewable energy within the grid system is quite high at this time. With the support of CCHP and GB's  
Figure 4: ADMM residual convergence process.  
Figure 5: Iteration situation of interactive power in electricity.  
output and considering energy storage, their charge-discharge coordination also helps to flatten the electric load demand of the IEMG system. Because the IEMG system has cooling and heating load demands, when CCHP has a larger cooling and heating load demand, its output is quite visible. From the figure, it can be seen that from 10:00 to 11:00, when the electric load is at peak and the cooling and heating load demand is also large, CCHP maintains a high output level. From 11:00 to 12:00, even though the electric load demand decreases, the cooling and heating load demand is still large, so CCHP still provides the electric load output. At 14:00, 16:00, 19:00, and 21:00, CCHP showcases a higher electric power output level, and under the alternation of EC and GB, it achieves the most optimal and reasonable operation of each facility. When CCHP's output is insufficient, IEMG will purchase electricity from the external grid to fulfill IEMG's internal electric load demand. When IEMG's internal electric load demand is low, IEMG will actively sell electricity to the external grid, thereby making certain profits.  
In terms of the optimal thermal power operation strategy results, it can be seen from Figure 7 that the thermal load curve is relatively smooth. From 8:00 a.m. to 10:00 p.m., the entire thermal load demand is at its peak stage. This time period is also the most concentrated stage of CCHP unit output, demonstrating that CCHP plays a significant role in compensating for the GB's output limitations. Meanwhile, thermal storage is also working during the peak period. However, when the thermal load demand is at a moderate stage, between 0:00 and 6:00, thermal storage primarily acts as heat storage. When the heat storage is almost full, to ensure storage capacity, it has to discharge heat. Thus, at 2:00 and 5:00, to coordinate with the output of the GB unit, the system opts for thermal storage to discharge heat to prevent excessive heat retention, which could affect the lifespan of the storage. From 23:00 to 24:00, when the system load is at its lowest, GB maintains its output, and the remaining thermal storage dissipates heat to maintain the system's thermal load balance.  
Figure 6: Optimal power operation strategy.  
Regarding the results of the optimal cold power operation strategy, as can be seen in Figure 8, the cold load curve also exhibits a flatter. From 0:00 to 8:00 in the morning, the whole cold load demand is in a flat phase. During this time, the EC unit's output is the most concentrated, revealing that the EC plays a valuable role in compensating for CCHP's output constraints. When the cold load demand is in the peak phase, from 9:00 to 20:00, the EC unit's output is in combination with CCHP's output of cold energy. From 21:00 to 24:00, at this time when the system load is at a low stage, the EC, alternating with the output of CCHP, achieves the balance of the cold load.