[time-nuts] Tuning GPSDO PID loop with sliders using simulation

[Erik Kaashoek]

Some time ago Ton van Baak advised me to use sliders and a graphical UI 
with dynamically updated charts for quick tuning of the PID parameters 
of a GPSDO loop in a simulation. As I could not find such a simulation 
and I'm not very efficient with graphics UI creation I created such a 
simulation with sliders in Excel.
Excel file is available here: http://athome.kaashoek.com/time-nuts/PID.xlsm
The cell with red numbers are input.
The simulation uses actual measured data from an OXCO and a GPS from 
here: http://www.leapsecond.com/pages/gpsdo-sim/
You can set the PID parameters using sliders (and the multipliers in red 
cells)to quickly see the impact of parameter changes.
New values are calculated (almost) instantaneous. Graphs are updated a 
bit slower.
The ADEV with tau 1,10, 100 and 1000 are calculated and various data is 
presented in charts.
Conditional coloring and value bars are used to get quick insight in the 
data
The current simulation covers 1900 seconds but if you have a fast 
computer you can extend the simulation
I hope I did not make any mistakes in the formula.
Erik.