We consider the problem of distributed optimal power flow (OPF) for
multi-area electric power systems. A novel distributed algorithm is proposed,
referred to as the rotated coordinate descent critical region exploration
(RCDCRE). It allows each entity to independently update its boundary
information and optimally solve its local OPF in an asynchronous fashion.
RCDCRE method stitches coordinate descent and parametric programming using
coordinate system rotation to reduce coordination, keep privacy and ensure
convergence. The solution process does not require warm starts and can iterate
from infeasible initial points using penalty-based formulations. The
effectiveness of RCDCRE is verified based on IEEE 2-area 44-bus and 4-area
472-bus systems