Basic generator control loops
Basic generator control loops
•
In
an interconnected power system , LFC (Load frequency control) and AVR
(Automatic voltage regulator) equipment's are installed for each generator. (
in fig LFC and AVR loops are shown).
•
Controllers
are set for a particular operating condition and take care of small changes in
load demand to maintain frequency and voltage within the specified limits.
•
Small
change in real power depend on rotar angle delta and thus frequency.
•
The
reactive is mainly dependent on voltage magnitude (i.e , on generator
excitation).
•
The
excitation system time constant is much smaller than the prime mover time
constant and its transient decay much faster and does not affect the LFC
dynamics. Therefor cross-coupling between LFC loop and AVR loop is negligible.
And the load frequency and excitation voltage control are analyzed
independently.
