×
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

Variable speed induction generator

Variable speed induction generator

Variable speed induction generator

(OP)
Hi guys,

We have a generator project that requires the induction generator to operate at a variable speed. We are hoping that by using an ABB ACS800-11 drive that we can generate into the local system. This drive has an "active front end" so that regenerated energy is transferred back into the system.

I am not too familiar with drives so can anyone offer any advice? Specifically, if we start the motor and run to say 2 hz, in order to excite the motor, does the drive then need to be changed into regenerative mode? Or do we just open the valves and set the required generator speed and the regeneration take care of itself? Presumably this is often done for cranes, however, these wouldn't be continuously regenerating. Would there be any issue with continuous regeneration?

Thanks in advance.
Paul

RE: Variable speed induction generator

A drive with genuine four-quadrant properties, which the ACS 800 with AFE is, adjusts itself to energy flow. No need to switch between different modes.

The "constant rectified voltage" property of a symmetrical three-phase system makes operation over a wide range of speeds possible. But not from superlow speeds like the 2 Hz you mention. The generator voltage is usually too low to produce any power into the grid at that speed. I guess you will be running at that speed only to start the system and then take it up in speed.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: Variable speed induction generator

Hi Gunnar;
Considering the volts/hertz ratio, how low can the speed/voltage go and still regenerate? What happens to the power factor?
Thanks
Bill

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

RE: Variable speed induction generator

I couldn't say. Depends a lot on the machine, I think.

 

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

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!


Resources