This paper presents the semismooth Newton-type algorithms for solving Optimal Power Flow (OPF) problems. Considering that there exist plentiful bounded constraints in OFF, the paper treats general inequality constraints and bounded constraints separately. By introducing a diagonal matrix and the nonlinear complementarity function, the Karush-Kuhn-Tucker (KKT) system of the OFF is transformed equivalently to a system of nonsmooth bounded constrained equations. Comparing with the classical OFF methods and the Nonlinear Complementarity Problem (NCP) method, this treatment has two remarkable advan...
