×
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

losses by using a Zig-zag transformer

losses by using a Zig-zag transformer

losses by using a Zig-zag transformer

(OP)
We are providing power to 25KV line through Step up transformer (4.16kv/25kv). The utility specified Delta(25Kv) Wye(4.16KV), and later on they asked us to add Zig-zag transformer to avoid the potential over voltage issues. We were asked to assess the losses as a result of using Delta-Wye+ zig-zag transformer.

one loss I can think of is,  the failure of the additional equipment-Zig-zag trnasformer would cause some loss over the years.

Are there any loss difference between Delta-wye+ Zig-zag and Wye-wye?

Any inputs would be appreciated.     

RE: losses by using a Zig-zag transformer

As it seems the network will have Delta/Wye + Zigzag trafo combination in place of Wye/Wye trafo, that is two trafos in place of one.
The utility wants to know a comparison of Watt losses between the two options.
What I guess is there will not be much difference in terms of watt losses between the two options. Additional loss in Zigzag trafo (only no-load loss need to be considered during normal operation) will be compensated by the less copper losses in Delta/Wye trafo (when compared to Wye/Wye trafo).
For numbers, a manufacturer will be in a better position to advise.

RE: losses by using a Zig-zag transformer

raghun,in a transformer whether deta  or star connected,copper losses will be the same as long as current density adopted is  same.In delta connection resistance will be 3 times more than star winding,but current will be one by root3 times lower than star connection.

RE: losses by using a Zig-zag transformer

In non fault operation the zig-zag transformer will have only no-load losses.

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!


Resources