Increase of corona discharge in HV machines due to high altitude

[genRman]

I am searching for information with regard to assessing the need for increased winding clearances in HV generators due to higher altitude siting, due to higher potential for corona discharge damage.

Clearly the atmospheric pressure will be reduced & hence the resistance to discharge reduce over an equal distance.

This is a particular design interest for discharge between generator stator winding bars, especially around the stator coil out-hangs (winding nose) regions.

Does anyone know of a good theory source?
I'd appreciate some help / advice / theory!

Thanks

 

[DougMSOE]

Try IRIS POWER ENGINEERING in Canada. they do have a web site.