Dear All,

We have GE make Gas Turbine LM2500 with Brush Generator. We are facing problem related to Voltage generated at Generator terminal voltage. Actual our Generation voltage at FSNL is 10.6 KV.

But now generation voltage is day by day reducing automatically at FSNL, from 10.6KV to 10.3KV. So it was create the difficulty during synchronization with Bus having voltage is 10.6 KV.

Can any guide to me for resolving this problem.

Thanks in advance.
uj

 

uj,

What other alarms are annunciated when this happens?

When did this problem begin? After a maintenance outage? After a turbine trip from load?

The problem sounds like a drifting off-line excitation setpoint. Does the site have a technician familiar with the exciter ("AVR") who can investigate and resolve?

Is it not possible to raise generator terminal voltage using the Auto Voltage RAISE capability? Some AVRs are in Manual mode when off line; have you tried the Manual Voltage RAISE capability?

Without knowing much more information about the generator exciter ("AVR") it's very difficult to offer much more help.

Please write back to let us know what you find!