Step input disturbance in os4 (negative result)

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Step disturbance

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try numerical simulation:
Simulink diagram (7900496):

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Nearly the same as in OS4.

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right: -0.2 vs 0.2

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try add twice.

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FOPD got worse after I got it work in OS4?

both discrete numerical simulation.

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Try to retest step response in os4 and write down the controllers.
FOPD:
NUM:
[0.946963179122833,-2.77792961698899,2.98392102212133,-1.40760552266944,0.267978964388861,-0.0129932830769816]
DEN:
[1,-2.94510699389959,3.17934233429781,-1.51000556757338,0.290497513211450,-0.0143972840431492]
IOPID:
p=1.58, i=0.182, d=1.49
FOPD>IOPID

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I tried to add a 0.5 gain before plant, FOPD is better.

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Nearly the same when constant 0.2 wind.