Gentlemen,
We have 4 x 920 Kw & 1 x 1100 Kw gas generating sets running in
parallel mode. In one of 920 Kw gensets we replaced the AVR two months
back & since then we have noticed that whenever there is a sudden load
change on the engine the PF of this particular engine doesn't respond
& it falls down to 0.6 to 0.65 lagging resulting to PF flctuations in
other engines as all of them are in parallel mode. Under this
cir***stences operator needs to ajust the PF by adjusting the
Motorised Potentiometer Pot resistance manully.
I feel that by adjusting the voltage droop from AVR this problem could
be resolved. However, I am not aware of the eexact realtion between
droop & PF. Is anybody aware of that increase in droop will impove
the PF during sudden load change or vice versa?
Please note that we maintain system PF as 0.8 lagging & before
replacemnt of AVR this problem was not there. Hence, somewhere it is
related to AVR fine tuning.
Please let me know your valuable opinions.
Regards.
Kishor
