Machine Dynamics: H factors

[Vegemite]

In order to calculate the longest fault clearance times permissible in an industrial power system I need 'stored energy constants' or H factors (in seconds) for the turboalternators. All machines are powered by 8,000 rpm steam turbines via gearboxes. These turbines are pass-out or non-condensing types supplying process steam in an aluminium refinery. The turboalternators are 50 Hz and as follows:
-- 1500 rpm, 12 MVA turboalternator
-- 1500 rpm, 20 MVA turboalternator
-- and 3000 rpm, 12 MVA turboalternator.

The H factor values need to include all of the rotating components, that is, steam turbine, gearbox and alternator.

As an alternative to the H factor the moment of inertia, J in kg M², for each component of the drive train and the speed of each component of the drive train together with the alternator's MVA rating would suffice.

 

[Alex68]

Please ask to the manufacturers of the alternators and the turbines.

 

[QCE]

Hello,

Maybe look at the thread I asked about H values last week. I got a very good answer from Marmite.

Basically you have the MVA and the speed and the H value is equal to 1/2Jw^2/MVA. So you just need J. you can look in the equipment spec's, ask the manufacturer or calculate it using for example J=1/2mr^2 for a disk.

Good luck.

 

[QCE]

Check the thread on : Hydropower Unit Inertia Requirement