×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Steam Turbine with Woodward 505e Speed Drop

Steam Turbine with Woodward 505e Speed Drop

Steam Turbine with Woodward 505e Speed Drop

(OP)
Hello,
We've been facing a problem with our 15 MW steam turbine recently. It has Woodward 505e governor controller installed and configured in 4% droop mode, although normally it is running alone. At other times (during startup), it is synchronized to other DGs.

The problem we faced recently was that when our turbine went up to about 11 MW (with all other DGs shut down), it kept normal for about 10-20 minutes. Then all of a sudden, without an increase in the load, its speed suddenly dropped from 3000 to 2950 rpm. Operators tried to increase Woodward speed setpoint manually, but it did not respond. Operators then switched off some 1.5 MW load manually and the turbine speed normalized to 3000 rpm. All this happened within 30-40 seconds. During this time there was no change in load, no change in steam pressure or flow (extraction was off at the time), no physical change in HP or LP valve.

The two questions which are looking to be answered are:
1. Why would the turbine suddenly slow down?
2. Even if somehow the turbine slowed down, why did 505e not respond by increasing its output to maintain the rpm?

Any suggestions would be most welcome!

RE: Steam Turbine with Woodward 505e Speed Drop

Possible a change in steam super-heat and resulting lower steam energy.
The symptoms may indicate an overload condition. Either too much load or too little steam energy
The inability to increase the speed manually and the recovery when the load is reduced indicate an overload.
Another possibility is a failing AVR.
If the excitation is increased on an islanded set, the voltage will rise. A rise in voltage may increase the MW enough to overload the set.
This is a factor worth checking and eliminating as a possible cause.
Could you have had a rise in back pressure? A flow restriction in the cooling tower circuit?

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

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper – Data Security and Know-How Protection
Our data is constantly exposed to the danger of being intercepted or stolen as it wends its way over global data networks. Data security measures and measures for protecting intellectual property should not, however, first be implemented when data is exchanged – companies must lay the foundation for these measures within their own organization. Download Now
White Paper – Collaboration in the PLM Context
The influence exerted by the Internet of Things (IoT) means that there is a steadily growing need for collaboration in industry. Partners from new industries and areas of application need to be integrated in cross-company business processes to ensure that the lifecycle of smart, connected products can be managed from end to end. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close