Speed fluctuation in VSD driven pump
Speed fluctuation in VSD driven pump
(OP)
we have 3 LPG pumps(2+1) operated by separate VSD Motors(690 KW).
Nowadays we have the below problem.For ex.
Pump A & B runs at speed of 3000 rpm, then if small voltage dip occurs, then pump A speed goes to 100 rpm, then automatically comes to 3000 rpm. This cycle occurs within 50 secs. Pump B runs in same speed without any problem.
Why it is happening..? how to rectify the problem...?
VSD is by ANSALDO.
Nowadays we have the below problem.For ex.
Pump A & B runs at speed of 3000 rpm, then if small voltage dip occurs, then pump A speed goes to 100 rpm, then automatically comes to 3000 rpm. This cycle occurs within 50 secs. Pump B runs in same speed without any problem.
Why it is happening..? how to rectify the problem...?
VSD is by ANSALDO.





RE: Speed fluctuation in VSD driven pump
If the drive has auto-restart then when the volts come back again, it will restart.
Check the settings between drive A and B. Maybe drive B has a function called 'kinetic buffering' or whatever they might call it. This will maintain control voltage longer than normal and ensure the drive does not cut out if sustaining a dip > the 'normal' 4-5 cycles.
RE: Speed fluctuation in VSD driven pump