Generation 1

[Guardiano]

Hi,

I have two 5 MW steam driven generators in parallel. The turbines have got identical governors with the same droop settings. The voltage on both alternators are regulated by identical AVRs with the same droop settings. However,the two sets are not sharing the load equally, with one loading at 3.5 MW and the second one at 4.5 MW and changing the droop setting on the AVRs have little effect on the sharing;
Any advice ?

Grundig

 

[rasevskii]

for Guardiano

The droop settings on the AVRs will not affect the MW output,only the reactive load sharing.

On the governors, are the valve openings the same or different at the MW loadings you have? Is there any load feedback to the governors/electronic or mechanical governors? Has something slipped in the linkages, was it always the same since commissioning or is this a new problem?

Does the load error remain constant or does it increase with load?

Are the panel instruments/transducers/load measurements accurate? Have a calibration check done.

Is this a new installation or is it many years in operation?

regards, rasevskii

 

[rasevskii]

for Guardiano

Another possibility is that these are back-pressure or extraction type turbines and that the pressure and flow conditions on the backpressure and/or extractions are different. Even at the same inlet valve positions then the loadings would be different.

regards, rasevskii

 

[waross]

A star for rasevskii. After verifying that there are no sticking valves, slipped or bent linkages, instrumentation errors, or back pressure issues adjust the set-points on the governors.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[esee135]

The others are correct. Are they speed-gate droop or speed-power droop governors? I assume that they are not fighting.