×
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

Resistance VS Reactor Grounding

Resistance VS Reactor Grounding

Resistance VS Reactor Grounding

(OP)
Hi all! Most of the time, we use a resistance grounding on transformers to limit the line to ground fault current.
But yesterday, I have tested an oil transformer that was using a reactor on the X0.  In my short experience in power
systems, I have seen many generators 13,8 kV grounded via a reactor  but not a transformer. That xfo is a 50 Mva, 120 to 2.3 kV. Why using one type of grounding over the other?

Thank!
 

RE: Resistance VS Reactor Grounding

It is either a resonant grounded system or low inductance grounded system.

Resonant grounding (Petersen Coil or Arc suppression coil)
It is a tuneable reactor connected in the transformer neutral to earth. The value of the reactance is chosen such that reactance current neutralises capacitance current. The current at the fault point is theoretical nil and unable to maintain the arc, hence the name. Normally used on systems above 15kV.

Low inductance grounding.
Normally reactance grounded systems is rarely used due to problems with overvoltages under arcing earth fault conditions, and the fact that the desired level of fault current higher is than the same size resistance grounded system. Therefore reactance grounding is usually not considered an alternative to resistance grounding.  
However, to achieve the same value as the resistor, the design of a reactor is smaller and thus cheaper - maybe a possible option to use it.

Failure seldom stops us, it is the fear for failure that stops us - Jack Lemmon

Make the best use of Eng-Tips.com
Read the Site Policies at FAQ731-376

RE: Resistance VS Reactor Grounding

reactors are less expensive, take up less room, and give off less heat...in most cases.

There are other engineering uses, but as always, price is a major factor.

JTK

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