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Synch Motor: AC power supply input to brushless excitation
2

Synch Motor: AC power supply input to brushless excitation

Synch Motor: AC power supply input to brushless excitation

(OP)
Is it a practice to have redundant input power supplies to excitation panel so as to take care of contingency of loss of one supply and consequent motor trip on field failure!
Appreciate sharing your thoughts / experience!

RE: Synch Motor: AC power supply input to brushless excitation

What size motor do you have?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Synch Motor: AC power supply input to brushless excitation

What industry is the motor used for?  What are the consequences of a Loss of Excitation Trip?

RE: Synch Motor: AC power supply input to brushless excitation

Not in the industries where I practice.

RE: Synch Motor: AC power supply input to brushless excitation

Usually only one power supply.  If it is only one motor very critical to the process we might think about it.  But when auxiliary power is lost, other support loads like lube oil pumps or vibration monitor control power may go down causing a trip anyway.  

Dual power supplies add complexity whcih can reduce reliability.

RE: Synch Motor: AC power supply input to brushless excitation

(OP)
Thanks for sharing your thoughts / experiences! The following is some some background to the issue:
This is a 13MW motor running a compressor. The drive is important for production. This company is part of O&G industry.
The issue is not about actual loss of power supply to the excitation panel. It is observed that during transient voltage dips (due to fault elsewhere in the system etc.) the excitation trips the motor. The input supply is monitored just by a simple auxiliary contactor that drops-off during the transient voltage dip leading to trip of the compressor drive.

RE: Synch Motor: AC power supply input to brushless excitation

Two power supplies fed from the same ultimate source will not help with a voltage dip at the source.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Synch Motor: AC power supply input to brushless excitation

I'd think you could easily fix that issue by addressing the reason for the drop-out instead of installing a whole new source. Change that contactor/relay to a proper voltage monitoring device.
 

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