## 5 Experimental Results  
The two MGs models are constructed in the MATLAB/Simulink platform version 2018b. Figure 5 shows the MG1 model, involving the aforementioned MG components. The left side shows the main grid as well as the PCC breaker that connects MG1 with the utility grid. An 11/0.4 kV transformer is installed between the main grid and the main station. The right side shows the connections between three loads and two PV systems. Following Algorithm 1, Figure 6a shows the current sensing model of the main grid. In this model, the current signal is monitored continuously and fed into a comparator. If the measured current reaches 0 A, the comparator will trigger the power difference (\(\Delta P\)) computation phase. Figure 6b shows the computation of \(\Delta P\) between the generated and the consumed power values. The generated power is the summation of acquired power signals of PV1, PV2, and the main grid, respectively. While the consumed power is the summation of the power signals of L1, L2, and L3, respectively. Both power generated and consumed signals are fed to RMS conversion block in order to calculate the \(\Delta P\) signal. Figure 6c illustrates the load shedding process in order to meet the power balance state. The process starts by utilizing the \(\Delta P\) continuously and forwarding it to an Analog to Digital Converter (ADC). Figure 5: MG1 model in MATLAB. Then, if \(\Delta P\) value is negative, the non-critical load is disconnected using an ON/OFF signal. For the computation of voltage sag percentage parameter, a voltage signal at the main station is continuously measured and fed to an RMS converter block to extract the RMS values. To evaluate the two MGs factors to different fault types, two faults have been inserted in sequence on different times and at different locations. Fault 1 occurred at bus 5, while fault 2 occurred at bus 1. Generally, electrical faults can be classified into two types, which are: Symmetric faults and Asymmetric faults [24]. Symmetric fault indicates the three-phase fault, which means that all phases are affected by the fault occurrence. The asymmetric fault is called unbalanced fault, which means  
Figure 6: Proposed methods modeling in MATLAB. **(a)**: current sensing model, **(b)**: computation of \(\Delta P\), (c)**: load shedding process. that not all the phases are affected by the fault. Typically, asymmetric faults are classified into three types, which are: Line-to-Line (L-L) fault, Line-to-Ground (L-G) fault and Line-to-Line-to-Ground (L-L-G) fault. The two inserted faults to our models are symmetric fault (fault 1) and asymmetric fault; L-L type (fault 2). As fault 1 is applied at t = 0.2 sec at bus 5 and cleared by the simultaneous opening of Circuit Breaker (CB). For MG\({}_{1}\), this fault has caused a decrease in the voltage parameter from 230 V to 39.7 V at bus 3, as shown in Figure 7a, resulting in a voltage sag of 82.7%. L2 will be disconnected as a result of the fault recovery process. Therefore, and based on Equation (8), the LoP\({}_{\text{R}}\) is about 31%. A second fault is applied at t = 0.42 sec at bus 1. This fault has a critical feature which is the location. To maintain the stable operation of MG\({}_{1}\), the PCC will be opened. Therefore, MG\({}_{1}\) will be transmitted from the connected mode to islanded mode at t = 0.5 sec. MG\({}_{1}\) will operate as an independent power source in the islanded mode, as shown in Figure 8. Figure 9a shows the current signal of L2, where the load has been disconnected at about t = 0.28 sec as bus 5 is disconnected. The voltage sag parameter has a value of 96%. Figure 7: RMS Voltage signal at bus 3: (a) MG\({}_{1}\), (b) MG\({}_{2}\). On the contrary, when applying the same sequence of faults for MG\({}_{2}\), L2 is still connected after fault1 via feeding it with another redundant path through bus 6. Hence, the LoP\({}_{\text{R}}\) is going to be zero, since there is no load disconnection.