Transformer noise

[Griseo]

I'm interested in calculation or estimation of audible noise in large power transformers (>100MVA). Is any practical method known for that? Any book or paper about noise calculation?
Thanks

 

[edison123]

see thread238-131967

 

[cuky2000]

Q#1: Is any practical method known for that?
[blue]Yes, there are several known methods for noise attennuation such as:
o Specifying units with a lower noise level than standard for new installations.
o Deploying sound barriers

o Designing a sound-absorbing enclosure. (Not very practical for large units).
o Provide active noise control to cancel the noise generated.

http://www.iav.ch/atq_e.html

[/blue]

Q#2: Any book or paper about noise calculation?

[blue]A theoretical method for calculation of sound attenuation by diffraction in through sound barrier wall is discussed on “AIEE Committee Report, Sound Barrier Walls for Transformers Trans. AIEE, 1960, vol 79, p. 932.”.[/blue]

_{Additional references:
STANDARDS:
o ANSI Standard C57-12-90
o NEMA Standard TRI-2-068-1954
o IEC 60076-10
WHITE PAPERS & PUBLICATIONS:
o Standard Handbook for Electrical Engineers, 13th edition, McGraw-Hill Edited by Fink & Betty, section 10, "Transformers" by W.J.McNutt, paragraph 94 to 98, equation 10-62.
o Maybee, N. An Integrated Noise Barrier and Containment System for Transformers. Proceedings of the Alberta Energy and Utilities Board Conference, Banff, Alberta, Canada, April 1998.
o Power Transformer Noise – Prevention and Care. Stanford Res. Institute. SRI project S2410, 1960.
o Transformer noise: determination of sound power level using the sound intensity measurement method- Electra 144, 1992.
o “Three-Stage Algorithm for Transformer Active Noise Control,” Sen M. Kuo and X. H. Jiang, Applied Signal Processing, vol. 4, no. 1, pp. 27-38, 1997.}

 

[Griseo]

I thank to my collegues for these replays. I'm sorry if I was not clear, but I'm searching for noise level calculation or estimation and not noise reducing methods!

 

[prc]

If you are looking for how much noise level will be for a particular size of trf look in NEMA TR-1 standard. If you are looking at calculation methods from trf parameters ,well it is pretty difficult .Generally speaking,noise level is a function of working flux density in core ( noise comes down with flux density ),weight of core ( noise up with core weight ) ,grade of CRGO used (domain refined or Hi-B grades have lower noise ) ,tank stiffening factors and type of core construction (type of joints ,core clamping etc ) .Manufacturers have their own internal formulae and software programmes for it .Some published papers are also available (IEEE & CIGRE )

 

[Vladpl]

Hi griseo

If you want to calculte transformer noise in all its aspects it can get a bit messy. easyest way is to measure noise with "sound level meater". There are few simple calculations you can perform as well but mostly they require this meter.

I design transformers myself and i know how dificult it can be when the transformer is noisy specialy the 3rd harmonic. The book I sort of found helpfull is nicknamed the "Transformer Bible" it is called:

Title: J&P Transformer Book
Author: Martin J Heathcote.

I hope this is going to be of some help to you.

Good Luck

Vlad