Curtis Instruments 1236 - Power Section

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TO PROVIDE BETTER CONTROL4HE MATHEMATICAL MODEL OF AN INDUCTION MOTOR
ISCOMPLEX5SINGASERIESOFREFERENCEFRAMETRANSFORMATIONSVECTORCONTROL
SIMPLIlESTHEMODELTOENABLEPRECISECONTROLOFTORQUEANDmUXSIMILARTOA
3EP%XMOTORCONTROLLER
&IGURE! SHOWS A TYPICAL DIAGRAM OFINDIRECT ROTOR mUX ORIENTATION
4HE INSTANTANEOUS PHASE CURRENTSARE TRANSFORMED TO THE ROTOR mUX REFER
ENCE
FRAMEUSING
ROTORSPEEDANDSLIPFREQUENCYWHICHMEANSTHATTHEMO
TORCURRENTS
ARENOWOBSERVEDFROMTHEVIEWPOINTOFROTATINGWITHTHEROTOR
mUX!SARESULTOFTHISTRANSFORMATIONTHECURRENTSNOWINWHATISCALLEDTHE
DQ
REFER
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ANDTHEMOTORCANACHIEVEHIGHEFlCIENCYANDDYNAMICRESPONSE
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4HECONTROLLERUSESANADVANCEDPULSEWIDTHMODULATIONTECHNIQUETO
MAXIMIZE THE UTILIZATION OF BATTERY VOLTAGE MINIMIZE HARMONIC LOSSES AND
INCREASESYSTEMEFlCIENCY4HISMETHODACHIEVESGREATERLINEARUTILIZATION
OFBATTERYVOLTAGETHEREBYEFFECTIVELYGETTINGMOREUSABLEMOTORPOWERTHAN
STANDARD07-ATTHESAMEBATTERYVOLTAGE
0OWER3ECTION
4HEPOWERSECTIONEFlCIENTLYGENERATESHIGHCURRENTPHASE!#SIGNALSFROM
THE$#BATTERYVOLTAGETODRIVETHE!#MOTORASREQUESTEDBYTHEMOTORCON
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OL
ALGORITHMS
4HE
POWERSECTION ISIMPLEMENTED ASTHREEHIGH FREQUENCY-/3&%4
HALFBRIDGEPOWERSTAGESCONTROLLEDBYTHREEPULSEWIDTHMODULATORSASSHOWN
IN&IGURE!%ACHHALFBRIDGEPOWERSTAGEISAPARALLELARRAYOFHIGHSIDEAND
LOWSIDEPOWER-/3&%4SMOUNTEDTO)NSULATED-ETAL3UBSTRATE)-3CIRCUIT
BOARD4HISTECHNOLOGYPROVIDESAVERYLOWTHERMALRESISTANCETOTHEHEATSINK
ANDENABLESHIGHPOWERCAPABILITYINACOMPACTAREA
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