The single line diagram (SLD) of a system is shown in Figure 1. At bus B, there is a non-linear load that acts as a source of harmonics in the system. 

1. Using the data in Table 1 and the conditions in Figure 1, evaluate the TDD value of the system based on IEEE 519-2014 standard! Assume the factor is 0.9 and the 5th, 7th, 11th order current harmonics at Bus A and B are the same. Current harmonics of order 5, 7 and 11 are 3 A, 1 A and 0.5 A respectively.
2. Based on the results obtained in point 1), does the system need mitigation? related to harmonic countermeasures? Explain!

Table 1 P = 3600 Kw Isc = 100 MVA BUS A 115 kV/20 kV non-linear loads elem P = 1100 Kw Isc = 50 MVA Utility Figure 1 B A BUS B