B. State Estimator
The state estimator is a central function of each network
control system. Its goal is to display the voltage phasors of the
most important nodes of the network and the energy flows
between them as accurately as possible.
Therefore, the network topology (status of CBs and
disconnectors), the real and reactive powers at the feeders and
the voltages at the busbars are monitored and measured.
The actual condition of the network is calculated from
these measured data and other network parameters (line
impedances, transformer data). Due to low data rates and
unsynchronized measurements, convergence problems can
occur during dynamic conditions. The state estimation can be
enhanced by using PMUs with time synchronized
measurement of the phasors of voltages and currents.