Lecture 6:Gain, Phase margins, designing with Bode plots, Compensators
نویسنده
چکیده
written for a particular gain. Then KGH = −1 so that a) when the amplitude of KGH is 1 or 0 dB and b) phase is 180o then we have the system just become unstable. Both the conditions have to be fulfilled. Hence, if we ask the question: How far is the system from instability ? We get two answers. The gain increment required at the frequency where phase is 180o and the phase increment required at the frequency where amplitude is 0 dB. The frequency where phase crosses 180o is called the phase crossover and the frequency where the amplitude crosses the 0dB point is called the gain crossover. Let us look at the nyquist plot for
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Tuning of Lead Compensators with Gain and Phase Margin Specifications
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