Resumo:
The use of advanced hardware and digital computers in electrical management systems potentially enhance
the supervision and control tasks in real time operation mode. These functions allow the safe operation of
electrical networks, which effectively improve the operator decision. Specifically, the state estimators applied
to power systems have an important role along with the SCADA systems, in order to evaluate the network
states as close as possible to the actual states of the monitored system.
This work evaluates a robust state estimator algorithm performance when it is written in object-oriented
programming language. The program makes use of the Iterative Weighted Least-squares method (IWLS)
with equality constraints (EC). The employed methodology has the feature of processing bad data during the
iterative search for the problem solution, even when it is extended to the state estimation problem with
equality constraints. In this work, the equality constraints can be modeled through two approaches: a)
Classical Weighting Method (WM); b) Weighting Method with Iterative Refinement (WMIR). Independently
from the fact that regular and/or pseudo measurements have been classified as leverage points, the
employed methodology, named IWLS-EC, allows the satisfactory processing of bad data and/or topology
errors.
The algorithm performances are explicitly tracked throughout the iterations carried out on a small example
system of 5 buses. Moreover, the proposed methodology is also evaluated in an actual system in the south
of Brazil with 126 buses, and also in other realistic systems with 340, 730 and 1916 buses. The obtained
results are compared, analyzed and commented on in the chapter that describes the set of simulations
carried out on test systems.
