The tap changer control with voltage regulator function OLATCC (on-load tap
changer controller) is designed for regulating the voltage of power transformers
with on-load tap changers in distribution substations. OLATCC provides a manual
or automatic voltage control of the power transformer using the raise and lower
signals to the on-load tap changer.
The automatic voltage regulation can be used in single or parallel transformer
applications. Parallel operation can be based on Master/Follower (M/F), Negative
Reactance Principle (NRP) or Minimizing Circulating Current (MCC).
OLATCC includes the line drop compensation (LDC) functionality, and the load
decrease is possible with a dynamic voltage reduction.
Either definite time characteristic (DT) or inverse time characteristic (IDMT) is
selectable for delays between the raising and lowering operations.
The function contains a blocking functionality. It is possible to block the voltage
control operations with an external signal or with the supervision functionality of
the function.