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Fig.29: Voltages and frequencies of Bus-600V and PCC with phase difference in fourth case study

Fig.30: Percentage of negative sequence in case 4.

E. The fifth case demonstrates how to detect and diagnose fault at time 3 sec. and a line-to-line fault at time 4 sec. as
the types of faults that occur in the grid, where various types shown in Figs. 31-32. The maximum values of the detailed
of faults were produced on the location between the coefficients acquired using the DWT and displayed in Table
transformer (TR4) and the main grid, and the discrete II for the adopted network are used to detect and classify
wavelet theory was used to find and diagnose these fault. faults. The value of Threshold (here it taken equal to 100)
Where a three-phase fault to ground occurred at time 1 sec., may be inferred from the table and used as a foundation for
a double-line fault to ground at time 2 sec., a line-to-ground comparison and categorization.