Bode Plot Question(Phase and Gain Margin)

[JohnielWhite]

I have been drawing a few bode diagram by hand and i am ask to find the phase and gain margin of the plot. Can someone please explain what are phase and gain margin, including how to determine it from the bode plot?

 

[berkeman]

I have been drawing a few bode diagram by hand and i am ask to find the phase and gain margin of the plot. Can someone please explain what are phase and gain margin, including how to determine it from the bode plot?

http://en.wikipedia.org/wiki/Bode_plot#Gain_margin_and_phase_margin

These are related to the stability of the system producing the Bode plot. Remember that you have an oscillation condition if your gain is >=1 and you have 180 degrees of phase shift in your negative feedback leg. Gain and Phase margin are two measures of how stable your system is.

 

[JohnielWhite]

I now have a better understanding of the significance of the bode plot to a control system. Thanks for your post.