  Recent advances in open source interior-point optimization methods and power
system related software have provided researchers and educators with the
necessary platform for simulating and optimizing power networks with
unprecedented convenience. Within the Matpower software platform a combination
of several different interior point optimization methods are provided and four
different optimal power flow (OPF) formulations are recently available: the
Polar-Power, Polar-Current, Cartesian-Power, and Cartesian-Current. The
robustness and reliability of interior-point methods for different OPF
formulations for minimizing the generation cost starting from different initial
guesses, for a wide range of networks provided in the Matpower library ranging
from 1951 buses to 193000 buses, will be investigated. Performance profiles are
presented for iteration counts, overall time, and memory consumption, revealing
the most reliable optimization method for the particular metric.
