ABB DCS 500B Description page 5

Current Difference Alarm.......................................................................................... 43
PI- Regulation .......................................................................................................... 44
Scaling of the gain KP .............................................................................................. 44
Scaling of the Time Constant KI ............................................................................... 44
Discontinuous Current Point..................................................................................... 44
Tuning of Current Regulator..................................................................................... 45
Firing Angle Limitation.............................................................................................. 45
Additional Commutation Reserve DXN..................................................................... 45
Example ................................................................................................................... 45
Network reactance ................................................................................................... 46
Short Circuit Current ................................................................................................ 46
400 A load................................................................................................................ 46
600 A load................................................................................................................ 46
DXN ......................................................................................................................... 46
Firing angle example ................................................................................................ 47
Note. ........................................................................................................................ 47
Status Indication for Bridge ...................................................................................... 47
• Field Excitation.................................................................................................................... 49
Selection of the Field Exciter .................................................................................... 50
Field Exciter Status .................................................................................................. 50
No Field Acknowledge Selected............................................................................... 50
Internal Diode Field Exciter SDCS-FEX-1..................................................................... 50
Internal Field Exciter SDCS-FEX-2 ............................................................................... 51
Acknowledge............................................................................................................ 51
External Field Exciter DCF503-0050............................................................................. 51
External Field Exciter DCF504-0050............................................................................. 51
AI/DI Connected Field Exciters ..................................................................................... 51
Acknowledge Selection ............................................................................................ 51
Use of the Analog Input Channel.............................................................................. 52
Calculation Example................................................................................................. 52
Two Field Exciters at the same time ............................................................................. 52
Field Current Settings .............................................................................................. 52
Free Wheeling Function ........................................................................................... 53
Trigger Point Setting of the Free Feeling Function ................................................... 53
Filter for Actual Field Current ................................................................................... 53
Field Current Controller ................................................................................................ 54
Field Reversal............................................................................................................... 54
Activating ................................................................................................................. 55
Field direction change hysteresis ............................................................................. 55
Force field direction.................................................................................................. 55
Field monitoring when changing direction ................................................................ 55
Opti-Torque .................................................................................................................. 56
Selection of OPTI-TORQUE..................................................................................... 57
Field current reduction using torque reference ......................................................... 57
Field monitoring when OPTI-TORQUE changes the field direction .......................... 58
Field current / FLUX linearisation ............................................................................. 58
Saturation................................................................................................................. 59
Linearisation procedure............................................................................................ 59
Field reduction when at stand-still ............................................................................ 59
DCS 500 Software Description
Contents
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