# Reducing Detrimental Communication Failure Impacts in Microgrids by Using Deep Learning Techniques
## 6 Proposed EMS and ESS Architecture
### System Performance Comparison for Different Link-Loss Occurring Instant  
Based on the proposed EMS-ESS system explained at the beginning of Section 6, it can be noted that there is a particular architecture for transmitting enhanced messages (every thirty minutes with forecast data for the next hour) so it is crucial to analyze the system's performance for different faulty scenarios. The difference between the analysis of this subsection with Section 6.1 is that, here, it is attempted to monitor the system performance regarding the occurrence time of the fault, while in the former analysis it was assumed that the ESS is loaded with forecasted setpoints for different time-windows.  
Two extreme cases are considered in this part, in the first case it is assumed that the communication link is lost for a whole hour, and this loss occurs immediately after an  
Figure 14: Internal power excess/deficit inside the MG (Two hour test).  
Figure 15: Internal power excess/deficit inside the MG (Four hour test).  
\begin{table}
\begin{tabular}{l l l l} \hline \hline  & **One Hour** & **Two Hours** & **Three Hours** \\ \hline ESS energy (charge/discharge) & & & \\ while receiving real-time data & 0.4367 kWh & 0.7239 kWh & 1.240 kWh \\ ESS energy (charge/discharge) & & & \\ working on forecast data & 0.3742 kWh & 0.6059 kWh & 0.7196 kWh \\ Energy exchanged with & & & \\ the grid (Export/import) & 0.0625 kWh & 0.1180 kWh & 0.5204 kWh \\ \hline \hline \end{tabular}
\end{table}
Table 5: Comparison between the PCC energy exchange for different scenarios.  
enhanced message was transmitted, therefore, the ESS has the necessary Prefs for the next hour. Due to the availability of forecasted Prefs for the duration of the fault, the ESS can properly operate. However, errors exist since forecasted values never exactly match with the real measurements. Figure 16 illustrates this error at each time step which will accumulate to a total of (0.0625 kWh) of electrical energy injected to the grid at the duration of this communication link loss. This can also be represented in terms of PCC power exchange RMSE (0.0273 kW) which indicates a significant improvement to the link-loss situation with no stored ESS power setpoints where the RMSE of the same trend is as high as (0.4464 kW).  
In the second fault scenario, the link loss happens just before the scheduled enhanced message is generated and transmitted from the EMS. Like the previous case, this fault also lasts for an hour. Regarding the circumstances, the Pref controller memory buffer only contains forecasted power references for the next 30 min and after that the setpoint will be changed to zero since there are no more data available. The error between ESS power references and the proper values that would have been generated and transmitted by the EMS with an operational link is illustrated in Figure 17. As it can be observed there is a sudden steep increase after 30 min, which is due to setting Pref values to zero from this point forward. During this fault, the total amount of (0.2774 kWh) of electrical energy is injected to the grid and the PCC power exchange RMSE is (0.3497 kW) which both are considerably greater than the previous scenario where the forecasted values were available for the whole communication outage period. However, the performance is still better than the base scenario where no mitigation technique was implemented.  
The two link-loss scenarios discussed above are illustratively explained in Figure 18.  
Figure 16: Error due to utilizing forecasted values, first case.  
Figure 17: Error due to utilizing forecasted values, second case.