What the best system to start large synchonous motors driving pumps?
What the best system to start large synchonous motors driving pumps?
(OP)
Hi folks,
We need to specify a system to start large synchonous motors driving water pumps. The motors are between 5 to 13 MW at 6.9kV. They are feed by a transformer 230/6.9kV, two motors per transformer.
Is the SCR soft-starter the best system for this application?
Thank you in advance for your reply.
Best regards,
Herivelto S. Bronzeado
Brasília, Brazil
We need to specify a system to start large synchonous motors driving water pumps. The motors are between 5 to 13 MW at 6.9kV. They are feed by a transformer 230/6.9kV, two motors per transformer.
Is the SCR soft-starter the best system for this application?
Thank you in advance for your reply.
Best regards,
Herivelto S. Bronzeado
Brasília, Brazil





RE: What the best system to start large synchonous motors driving pumps?
A solid-state reduced-voltage for a 13,000 kVA motor is going to be expensive. LCI adjustable frequency drives are probably still a viable option for motors this size.
RE: What the best system to start large synchonous motors driving pumps?
RE: What the best system to start large synchonous motors driving pumps?
Then if you start to consider the possible benefits of varying the speed to match flow requirements, the next level up, a VFD, might be worth considering as well. LCIs are of course VFDs, but tnot the most efficient ones if running below full speed, so a CSI or VSI might be a better choice.
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RE: What the best system to start large synchonous motors driving pumps?
we balanced the cost of the solid-state soft start versus the cost of an autotransformer-based system.
I am expecting good results.
old field guy
RE: What the best system to start large synchonous motors driving pumps?
Good luck with that...
"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: What the best system to start large synchonous motors driving pumps?
Cheers!
Herivelto
Best Regards,
Herivelto S. Bronzeado
Ministério da Integração Nacional - MI
Brasília, Brazil
RE: What the best system to start large synchonous motors driving pumps?
Curious about your distinction between LCIs and CSIs. Always believed one was a subset of the other.