An interior-point method for nonlinear optimal power flow using voltage rectangular coordinates

The paper describes the solution of an optimal power flow (OPF) problem in rectangular form by an interior-point method (IPM) for nonlinear programming. Some OPF variants when formulated in rectangular form have quadratic objective and quadratic constraints. Such quadratic features allow for ease of matrix setup, and inexpensive incorporation of higher-order information in a predictor-corrector procedure that generally improves IPM performance. The mathematical development of the IPM in the paper is based on a general nonlinear programming problem. Issues in implementation to solve the rectangular OPF are discussed. Computational tests apply the IPM to both the rectangular and polar OPF versions. Test results show that both algorithms perform extremely well