Curtis Instruments 1236 - Speed Controller and Feedforward Parameters

#URTIS-ANUAL/3 

02/'2!--!",%0!2!-%4%23 3PEED#ONTROLLER6ELOCITY&EEDFORWARD0ARAMETERS30%%$-/$%
n30%%$-/$% 30%%$#/.42/,,%2-%.5
  !,,/7!",% 
 0!2!-%4%2 2!.'% $%3#2)04)/.
-AX3PEED nRPM $ElNESTHEMAXIMUMREQUESTEDMOTORRPMATFULLTHROTTLE0ARTIALLYAPPLIED
-AX?3PEED?3PD- n THROTTLEISSCALEDPROPORTIONATELYEGAPPLIEDTHROTTLECORRESPONDSTO
AREQUESTF
OROFTHESET-AX3PEED6ALUE
 )F-AX?3PEED?3PD-
ISSETRPMTHROUGH6#,OR#!.THETHROTTLE
REQUESTISZ
EROED
 .OTE
4HEMAXIMUMMOTORRPMISSUBJECTTOTHECONSTRAINTSONPAGE
+P n $ETER
MINESHOWAGGRESSIVELYTHESPEEDCONTROLLERATTEMPTSTOMATCH
+P?3PD- n THESPEEDOFTHEMOTORTOTHECOMMANDEDSPEED,ARGERVALUESPROVIDE
TIGHTERCONTROL

)FTHE
GAINISSETTOOHIGHYOUMAYEXPERIENCEOSCILLATIONSASTHE
CONTROLLERTRIESTOCONTROLSPEED)FITISSETTOOLOWTHEMOTORMAYBEHAVE
SLUGGISHLYANDBEDIFlCULTTOCONTROL
+I n
 4HE
INTEGRALTERM+IFORCESZEROSTEADYSTATEERRORSOTHEMOTORWILLRUN
+I?3PD- n ATEXACTLYTHECOMMANDEDSPEED,ARGERVALUESPROVIDETIGHTERCONTROL
 )FTHE
GAINISSETTOOHIGHYOUMAYEXPERIENCEOSCILLATIONSASTHE
CONTROLLERTRIESTOCONTROLSPEED)FITISSETTOOLOWTHEMOTORMAYTAKE
A
LONGTIME
TOAPPROACHTHEEXACTCOMMANDEDSPEED
n30%%$-/$% 6%,/#)49&%%$&/27!2$-%.5 ;/04)/.!,=
  !,,/7!",% 
 0!2!-%4%2 2!.'% $%3#2)04)/.
+VFF n! 4HISVELOCITYFEEDFORWARDTERMISDESIGNEDTOIMPROVETHROTTLERESPONSIVENESS
+VFF?3PD- n ANDSPEEDCONTROLLERPERFORMANCEESPECIALLYATLOWSPEEDS
 &OR
TRACTIONSYSTEMSSETITTOnOFTHECURRENTNEEDEDTOMAINTAIN
AVERYLOWSPEEDUNLOADEDONmATGROUND

&OR
APUMPSYSTEMSETITTOTHELOWESTLOADCURRENTIETHECURRENT
RUNNINGATTHEMINIMUMLOAD!LTERNATIVELYTHERESPONSIVENESSOFAPUMP
SPEEDCONTROLLOOPCANBESIGNIlCANTLYENHANCEDBYUSINGA6#,PROGRAMTO
CONTINUOUSLYUPDATETHISPARAMETERTOTHEAPPROPRIATEVALUEASEACHPUMP
LOADISREQUESTED
"UILD2ATE nSEC $ETERMINESHOWFASTTHE+VFFTERMBUILDSUP
6EL?&&?"UILD?2ATE?3PD- n  &ORTRACTIONSYSTEMSIFYOUFEELORHEARTHEMECHANICALSLOPPICKUP
ABRUPTLYWHENYOUMOVETHETHROTTLEFROMNEUTRALTOAVERYSMALLVALUE
SLO
WINGTHE
BUILDRATEIESETTINGITTOAHIGHERVALUEWILLSOFTENTHEFEEL
 &OR
APUMPSYSTEMSTARTWITHTHISPARAMETERATTHEMINIMUMSETTING
3LOWINGITDOWNIESETTINGITTOAHIGHERVALUEWILLREDUCESPEEDOVERSHOOT
IFTOOMUCHFEEDFORWARDHASBEENCOMMANDED
2ELEASE2ATE nSEC $ETERMINESHOWFASTTHE+VFFTERMRELEASES)FTHERELEASESEEMSTOOABRUPT
6EL?&&?2ELEASE?2ATE?3PD- n SLOWINGTHERELEASERATEIESETTINGITTOAHIGHERVALUEWILLSOFTENTHEFEEL

)TSHOULDBESETFASTENOUGHIEATALOWENOUGHVALUETOPREVENTTHE
VEHICLEFROMRUNNINGONAFTERTHROTTLERELEASE