The Neutral grounding for Power transformer

For medium voltage network, the solidly grounded neutral is not preferred, grounding through resistance is preferable in order to reduce the ground fault current in comparison with the solidly grounded system. That is regardless of what type of load is connected to the transformer.

Another question comes up now, is it better to use an isolated transformer (ungrounded)?

in special cases (Yes), but with a drawback of high voltage attack, usually cased by sorts of switching transient.

See Chapter 1 of IEEE standard # 142 - 1991

I have an e-copy but I don't know how can I attach it...

Good Luck... Samak

Despite grounding resistance a coil, so called Petersen coil is generally used to ground the neutral point. Normally there is no current over this coil but in case of any error it emphasises the error current and makes the job of protection easier.

hi i m nandita.i read ur views about neutral grounding.u also talked about the related ieee std. can u pls send me a soft copy of the same at my e-mail id: nandu_rm@hotmail.com .

Hi Nandita,

you can find details on Petersen coil on the following links:

http://www.a-eberle.de/pdf/iste216_pp1.PDF

http://www.areva-td.com/solutions/liblocal/docs/LegacyProducts/kceu142-242salesen.pdf

Thnaks.

The attchment u can send by e mail on

niranjan.shastri@yahho.co.in

nascon

hi samak

could u pls attache the E-copy of Chapter 1 of IEEE standard # 142 - 1991 to dis id manirul.islam@neilsoft.com

Can you please send me the said e-copy at solaaderinwale@yahoo.co.uk.

Dear Friends:

IEEE 142 is a 10 Mbyte pdf file... may you recommend me another way to submit this file as it is too big to be attached with an email.

I'm a member of windows live messenger. It may be used to transfer that file.

However, you can add my email to your body list if you are a member.

Good Luck... Ahmad Samak

HI , Mr ahmad

I am ahmed yuonis , postgraduate student , garyounis univercity , libya .

please try to send the ieee.stand. for grounding power transformers to my email

becuse my interest field in this subject.

thanks

my email : alorfi69@yahoo.com

Dear Ahmad

I live in Alexandria, Egypt.

I'm glad to meet you, I spent 3 years in El-Zawya while I was 8 years old.

Please, read post # 8, my email is samak@alexandria.cc

Regards

Samak