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Entry  Thu Feb 15 10:36:22 2018, awade, DailyProgress, TempCtrl, New PID beta python script and tuning BN frequency PID PIDLocker_scripts_finitediffAndNewBeta.zip
    Reply  Fri Feb 23 07:49:50 2018, rana, DailyProgress, TempCtrl, New PID beta python script and tuning BN frequency PID 
Message ID: 2101     Entry time: Fri Feb 23 07:49:50 2018     In reply to: 2092
Author: rana 
Type: DailyProgress 
Category: TempCtrl 
Subject: New PID beta python script and tuning BN frequency PID 

Something new in PID loops ! Awesome. Let's see some before/after comparison time series and spectra.

Quote:

The differential term is approximated by the backward difference (see ch 10, Åström and Murray). For the case where the derivative is filtered with the characteristic time Tf the D term is given by 

D_k = \frac{K_d}{T_f + \Delta t} (p_k-p_{k-1}) + \frac{T_f}{T_f + \Delta t} D_{k-1}

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