Summary of Gain and Phase Margins Explained!

00:00:00 - 00:10:00

In this video, the author explains gain and phase margin, and how they affect a system. He also demonstrates an example of an open-loop system with infinite gain margin and explains how the sensitivity of the system can be used to determine if the system is stable.

• 00:00:00 In this video, gain and phase margins are explained. Gain is the proportion of the magnitude of the output to the magnitude of the input at steady state, while phase is the shift of the signal measured in angle or just fractions of a wavelength. A bode plot shows the gain and phase of a system across the entire frequency spectrum. Margin is the extra amount of something that you can use in case you need it for stability. Gain and phase margin can be different at different frequencies, and they usually are. When designing a system, you should account for margin to ensure stability.
• 00:05:00 The video explains how process variations can create instability in a closed-loop system, and how to account for it by designing in margin. It also explains how to measure stability margins and show how they depend on gain and delay. Finally, the video shows how to calculate the gain margin and phase margin for a particular transfer function.
• 00:10:00 In this video, the author explains what gain and phase margin are, how they affect a system, and how to determine if a system is stable. He also demonstrates an example of an open-loop system with infinite gain margin and explains how the sensitivity of the system can be used to determine if the system is stable.