Specifications

zgrid
16-230
16zgrid
Purpose Generate a z-plane grid of constant damping factors and natural frequencies
Syntax zgrid
zgrid(z,wn)
Description zgrid generates, for root locus and pole-zero maps, a grid of constant damping
factors from zero to one in steps of 0.1 and natural frequencies from zero to
in steps of , and plots the grid over the current axis. If the current axis
contains a discrete z-plane root locus diagram or pole-zero map,
zgrid draws
the grid over the plot without altering the current axis limits.
zgrid(z,wn) plots a grid of constant damping factor and natural frequency
linesforthedampingfactorsandnormalizednaturalfrequenciesin thevectors
z and wn, respectively. If the current axis contains a discrete z-plane root locus
diagram or pole-zero map,
zgrid(z,wn) draws the grid over the plot. The
frequency lines for unnormalized (true) frequencies can be plotted using
zgrid(z,wn/Ts)
where Ts isthesampletime.
zgrid([],[]) draws the unit circle.
Alternatively, you can select
Grid from the right-click menu to generate the
same z-plane grid.
Example Plot z-plane grid lines on the root locus for the system
by typing
H = tf([2 -3.4 1.5],[1 -1.6 0.8],-1)
Transfer function:
2 z^2 - 3.4 z + 1.5
-------------------
z^2 - 1.6 z + 0.8
Sampling time: unspecified
π
π
10
⁄
Hz
()
2z
2
3.4z– 1.5+
z
2
1.6z– 0.8+
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