How to Determine the Stability of System using Polar Plot?(Complete Stability Analysis )

How to Determine the Stability of System using Polar Plot? Stability Analysis using Critical Point 1.If C.P. is not enclosed by Polar plot →Stable System 2. If C.P. is enclosed by Polar plot → Un-Stable System 3.If C.P. is at the point of intersection of polar plot with - -1800 Line →Marginally Stable System. Stability Analysis w.r.t. Gain Margin and Phase Margin 1.If G.M & P.M are positive ⇒ The system is said to be Stable system. 2.If G.M & P.M are negative ⇒ The system is said to be Un-stable system. 3.If G.M & P.M = 0 ⇒ The system is said to be Marginally stable system. Stability Analysis w.r.t. ωpc & ωgc 1.System is Stable if → ωgc smaller than ωpc 2.System is unstable if → ωgc greater than ωpc 3.System is marginally stable if → ωgc = ωpc #HowtoFindStabiltyofSystemusingPolarPlot? #StabilityAnalysiswithPolarPLot