Table 4.

Poles and damping ratio of optimization techniques using PID controller.

HS-DMOA-PID	Pole	-100	-3.96 + 4.80i	-2.91-5.28i	-2.52 + 0.32i	-0.295
	Damping ratio	1	0.6361	0.6361	0.9918	0.9918
LUS6	Pole	-102	-5.03-14.7i	-5.03-14.7i	-0.5 + 0.88i	-0.5 + 0.88i
	Damping ratio	1	0.323	0.323	0.502	0.502
HSA6	Pole	-103	-5.04 + 15.1i	-5.04 + 15.1i	-0.45 + 0.85i	-0.45 + 0.85i
	Damping ratio	1	0.316	0.316	0.465	0.465
TLBO-PID6	Pole	-102	-5.02 + 14.7i	-5.02-14.7i	-0.52 + 0.86i	-0.52-0.86i
	Damping ratio	1	0.323	0.323	0.511	0.511