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Entry  Wed Aug 12 16:30:01 2009, Dmass, Computing, PMC, PMC Loop Changed PMCOLTF_Boost.pdfPMCTranErrBoost.pdf
    Reply  Wed Aug 19 11:27:59 2009, rob, Computing, PMC, PMC Loop Changed 
Message ID: 276     Entry time: Wed Aug 19 11:27:59 2009     In reply to: 259
Author: rob 
Type: Computing 
Category: PMC 
Subject: PMC Loop Changed 

Quote:

My locking algorithm:

  • Get close to the fringe and let the system spaz out using my 72 Hz PMC PZT pole for locking
  • Engage FM4, which is a zero at 72 Hz and a pole at 1 Hz
  • Engage my Boost stages
  • Engage my integrator (zero at 1 Hz and a pole at zero)

 

You should try just leaving FM4 on all the time.  Since the purpose of this FM is to make the loop 1/f everywhere from 1Hz to several kHz, the loop should be stable over very large gain ranges.  This makes locking much easier.

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