*7.1. Switching of Line Feeder*

The event of switching on and off of the line feeder was realized by opening the circuit breaker (CB) between nodes 671 and 692 at 4th cycle and re-closing the CB at 8th cycle. Results for the period of 12 cycles in the event of switching of line feeder are presented in Figure 14. It is observed that the current and voltage waveforms are distorted with small magnitude at the time of feeder operation (on/off) as depicted in Figure 14a,b, respectively. It is inferred from Figure 14c that magnitude of WD-index increases at the time of feeder tripping and re-closing. Figure 14d indicates that the ALN-index has high magnitude peaks at the time of re-closing of the feeder. However, small magnitude transients are observed at the moment of feeder tripping. Figure 14e gives an indication that FI has a lower magnitude compared to threshold at both the events of tripping as well as re-closing of feeder. However, small magnitude peaks are observed at the moment of feeder tripping as well as re-closing, where feeder re-closing event has a large effect compared to tripping event. A high resolution plot of FI is illustrated in Figure 14f.

**Figure 14.** Recognition of event of switching of line feeder (**a**) current waveform (**b**) voltage waveform (**c**) WD-index (**d**) ALN-index (**e**) FI (f) high resolution plot of FI.
