Jump to content

Nyquist-plot

Add links
From Wikipedia, the free encyclopedia
This is an old revision of this page, as edited by Ganzor (talk | contribs) at 23:13, 14 December 2002 (Nyquist-plot description). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)

The Nyquist plot is a way of describing a system based on how it reacts to different frequensies. The Nyquist-plot states the amplification/attenuation and phase-shift of the signal. The Nyquist-plot is in the complex plane. The phase-shift of a signal with frequency (ω) is represented by the argument and the magnitude is represented by the length of a vector from origo in the direction described by the argument.

The Nyquist is very usefull in looking at the stability of a an open negative-feedback-system. If the magnitudefunktion of a frequency that is phase-shifted 180° is one or more the closed-system will be instabil.

Also see Bode-plot

Retrieved from "https://en.wikipedia.org/w/index.php?title=Nyquist-plot&oldid=495215"