Notes on Frequency Methods: Gain Margin Phase Margin, Delays, and the Nyquist Map

نویسنده

  • Daniel S. Stutts
چکیده

Using frequency methods, it is possible to determine a great deal of information from the open-loop transfer function. One of the most important facts about a given system which may be determined via frequency methods is the relative stability of the system. There are two principal measures of system stability determined via frequency methods: Gain Margin, and Phase Margin. These two measures may be read from Nyquist plots or Bode plots, both of which may be easily constructed using MATLAB. Below, we will first discuss the Nyquist criteria, and work an example, then we will apply MATLAB’s Bode plotting capabilities to obtain the same information.

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تاریخ انتشار 2012