Trip Issue

Machine Info:
Gas Turbine: GE 9FA,Mark VIe control
Cause of Shut down/Trip:
ST> Tripped due Auxiliary Power failure because of Voltage fluctuation from Grid side.
Before Unit Trip:
Single/Combined cycle
:Combine Cycle

Reason for Trip:
Problem during GT Trip:
Due to Grid voltage fluctuation, damper signal loss power and Limit switch sensor troubleshoot fault alarm come and thus GT trip due to Damper limit get no feedback then GT trip

Sequence of Trip
From 6.6KV Load A Incoming Breaker A 10BFAA01 TRIP >>

ST MAIN LUBE OIL A&B TRIP >>
DC Operating Lube Oil pump operate >>
ST Low Lube Oil Pressure Come >>
ST Trip>>
10BFA07 Coupler delayed to operate>>
Damper Associated Breaker from 6.6KV Load B bus bar 10BMCO2 Trip>>
In the workstation GT alarm found in Mark VIe
Damper Limit switch troubleshoot fault alarm come >>
Damper Feedback Signal Loss >>
GT Trip

Analysis:
Due to Grid Voltage fluctuation Turbine Hall 10BFA01 Incoming Breaker tripped:
This is the incoming breaker 10BFA01 of Bus-A fed from 6.6KV Load A and transform to ~415 V>> breaker 10BFA01 , this incoming breaker remained de-energized because of the faulty Under Voltage relay or ABB multi functional 3 phase RMS monitoring relay
 
Machine Info:
Gas Turbine: GE 9FA,Mark VIe control
Cause of Shut down/Trip:
ST> Tripped due Auxiliary Power failure because of Voltage fluctuation from Grid side.
Before Unit Trip:
Single/Combined cycle
:Combine Cycle

Reason for Trip:
Problem during GT Trip:
Due to Grid voltage fluctuation, damper signal loss power and Limit switch sensor troubleshoot fault alarm come and thus GT trip due to Damper limit get no feedback then GT trip

Sequence of Trip
From 6.6KV Load A Incoming Breaker A 10BFAA01 TRIP >>

ST MAIN LUBE OIL A&B TRIP >>
DC Operating Lube Oil pump operate >>
ST Low Lube Oil Pressure Come >>
ST Trip>>
10BFA07 Coupler delayed to operate>>
Damper Associated Breaker from 6.6KV Load B bus bar 10BMCO2 Trip>>
In the workstation GT alarm found in Mark VIe
Damper Limit switch troubleshoot fault alarm come >>
Damper Feedback Signal Loss >>
GT Trip

Analysis:
Due to Grid Voltage fluctuation Turbine Hall 10BFA01 Incoming Breaker tripped:
This is the incoming breaker 10BFA01 of Bus-A fed from 6.6KV Load A and transform to ~415 V>> breaker 10BFA01 , this incoming breaker remained de-energized because of the faulty Under Voltage relay or ABB multi functional 3 phase RMS monitoring relay
Abby,

Could you write, us some feeback regarding the issue, you have been faced , and if you solved the problem?

Thanks for sharing,
Controlsguy25.
 
Machine Info:
Gas Turbine: GE 9FA,Mark VIe control
Cause of Shut down/Trip:
ST> Tripped due Auxiliary Power failure because of Voltage fluctuation from Grid side.
Before Unit Trip:
Single/Combined cycle
:Combine Cycle

Reason for Trip:
Problem during GT Trip:
Due to Grid voltage fluctuation, damper signal loss power and Limit switch sensor troubleshoot fault alarm come and thus GT trip due to Damper limit get no feedback then GT trip

Sequence of Trip
From 6.6KV Load A Incoming Breaker A 10BFAA01 TRIP >>

ST MAIN LUBE OIL A&B TRIP >>
DC Operating Lube Oil pump operate >>
ST Low Lube Oil Pressure Come >>
ST Trip>>
10BFA07 Coupler delayed to operate>>
Damper Associated Breaker from 6.6KV Load B bus bar 10BMCO2 Trip>>
In the workstation GT alarm found in Mark VIe
Damper Limit switch troubleshoot fault alarm come >>
Damper Feedback Signal Loss >>
GT Trip

Analysis:
Due to Grid Voltage fluctuation Turbine Hall 10BFA01 Incoming Breaker tripped:
This is the incoming breaker 10BFA01 of Bus-A fed from 6.6KV Load A and transform to ~415 V>> breaker 10BFA01 , this incoming breaker remained de-energized because of the faulty Under Voltage relay or ABB multi functional 3 phase RMS monitoring relay
Abby,

Can you tell us how this issue evolved at your site?
Thank you for sharing feedback!

ControlsGuy25.
 
Thank you everyone for your response . Sorry for late reply. The problem became resolved. Later i will discuss what happened and how we resolve the issue.
 
Thank you everyone for your response . Sorry for late reply. The problem became resolved. Later i will discuss what happened and how we resolve the issue.
Abby,

You told us that you will share here solution for the issue you have been face...
We still did not see any valuable thread or post from you... Since your last one...
That's not just like this.. You know it's not so easy to support people around the world from remote site like control. Com...
And now you are posting another thread, asking for questions on ST&GT Startup curves& operations...
That's not the way it is working here
..
Pkz change your behavior /attitude...
We are humans being before to be professional experts...

Cheers,
Controls guy25.
 
Abby,

You told us that you will share here the solution for the issue you have been faced...
We still did not see any valuable thread or post from you... Since your last one...

-------------------------------------------------------------------------------------------------------------------
Hi

I am sorry for taking too much time. @ControlsGuy25

As I told you, I will share the issues which we already faced during the Time of TRIP. So, here it is..................

The schematic @PhilCorso of all trend incidents is attached in this PDF (Trip of ST_HRSG_GT).

The following issues below are attached in this PDF/////

> Single line/Schematic diagram of the system
> Trend of GRID fluctuating voltage
> Trend of breaker trip with schematic
> Other schematic and trend relevant to the trip

I hope, it will help to analyze the true reason behind the Trip.

I am appreciated for your feedback.

Thank You
 

Attachments

Hello All,

Abby thank you for posting these elements here as promised before!
Much appreciated !
We can learn all toghether from this case !

So is the RCA related to Damper limit switch, feed back signal lost during such event and so PLC get no powered ?

How about UPS or watch dog or any protection on these plc ...
You surely need to remediate about how to avoid such event/issue in the future to run this plant smoothly in case of Grid voltage fluctuations!

I am bit surprised that "PLC lost power" as your statement...

Thanks for your answers,

Regards,
James
 
James,
Thanks for your feedback。

I am also confused about PLC restart.I still don't know why UPS unable to support on that time..
There is another mystery ST trip..Low lube oil pressure// although there is a backup// DC support incase of Low Lube oil pressure.

Regards
Abby
 
James,
Thanks for your feedback。

I am also confused about PLC restart.I still don't know why UPS unable to support on that time..
There is another mystery ST trip..Low lube oil pressure// although there is a backup// DC support incase of Low Lube oil pressure.

Regards
Abby
Abby,

Thank you for your reply.

Well I thinks that such situation can be avoided in the future..

What you need to do, is getting trends from ST controls systems for reviewing , and Investigate on why PLC for Bypass diverter damper did not what they were supposed to do in such situation...

Do not hesitate to share your investigations!

Regards,
James
 
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