Nichols Plot Generator
Description| How it works| Gain and Phase MarginsThis app will generate the Nichols Plot given a transfer function of the form
F(s) = (a + bs) e-ts / (g + hs).
Nichols plot shows open loop gain in decibels against open loop phase shift. It allows easy determination of robustness margins.
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.xlsx file (42 KB)How to use
The use of this app is quite straightforward, simply key in the values of a, b, g, h and t into the cells B6 through B10. Key in the frequency range into the cells B13 and B14. Note that the units of frequency is rad/time. The Nichols plot is generated.Lets say we wish to obtain the Nichols plot of 2e-3s/(1 + 5s), from 0.01 rad/s to 100 rad/s. We have
a = 2,
b = 0,
g =1,
h = 5 and
t = 3.
Key in these values and the range. If done correctly, you should see the screen below.
Also See:
PID Loop SimulatorLaplace to Time Domain Converter
Nyquist Plot Generator
PI Control of First Order Process
PI Control of Integrating Process