Member Login
member
passwd
remember me on
this computer.

- join now -
- forgot username or password? -

Search

Jump to a Date

Sponsored Communities
Cool stuff
Select a topic of interest:
...and press:
Neat Stuff
Control.com Stuff

Visit our shop for nerds in control lifestyle products.

Fortune
Real Users are afraid they'll break the machine -- but they're never
afraid to break your face.
RSS Feed
RSS feed Use this link to get an RSS feed of the Control.com article flow, for private, non-commercial use only:
www.control.com/rss/
To get a personalized feed, become a member at no cost.
Select a Page Style
Select one of the following styles:
- BluFu
- Classic
(cookies required)
advertisement
from the Operations department...
Negative Phase Sequencing
Continuous process industries, DCS questions. topic
Posted by Turbine 7777 on 27 February, 2008 - 11:39 pm
What are the signs that the unit should be shutdown due to line unbalance? Are Phase Temps a good or the only indication? What can be done to fix the problem or where who one start to troubleshoot the problem. This happens at 1.0 MW or at 8.0 MW. Does come down with lowering load.

Thanks


Posted by Phil Corso, PE on 28 February, 2008 - 11:11 pm
Responding to Turbine 7777’s 27-Feb-08 (23:39) call for help... negative sequence is usually caused by voltage or current unbalance.

Normally, the generator is able to tolerate a small amount of continuous negative sequence current. Exact amount is very dependent on machine characteristics! Please send operating details:

1) Nameplate data, i.e., MVA, pf, freq, poles, kV, A, driver type.

2) Exciter volts and amps.

3) Actual phase currents.

4) Actual phase-phase volts.

5) Actual phase-neutral volts.

6) Actual exciter volts and amps.

Regards, Phil Corso (cepsicon@aol.com)


Posted by Phil Corso, PE on 1 March, 2008 - 12:28 am
Turbine 7777, although the lead-in to your thread asks about negative sequence impacting gas turbine operation, the thread references only the generator!

Please clarify your query. Are you inquiring about the turbine or the generator or both?

Regards, Phil Corso (cepsicon@aol.com)


Posted by Turbine 7777 on 1 March, 2008 - 12:09 pm
I will send in tomorrow, as I am at home and do not have the exact data you requested. Thanks for the reply.

From Control Engineering magazine...
Related articles from Control Engineering magazine
Above articles copyright 2008 Reed Business Information. Subject to its Terms of Use.
Your use of this site is subject to the terms and conditions set forth under Legal Notices and the Privacy Policy. Please read those terms and conditions carefully. Subject to the rights expressly reserved to others under Legal Notices, the content of this site and the compilation thereof is © 1999-2008 Control Technology Corporation. All rights reserved.

Users of this site are benefiting from open source technologies, including PHP, MySQL and Apache. Be happy.

Internet Explorer 6.0 Fix

Advertisement
Our Advertisers
Help keep our servers running...
Patronize our advertisers!