In view of the adverse effect of the corrector in calculating available transfer capability with the predictor-corrector interior point method

an improved multiple-centrality-correction interior point algorithm is proposed for this purpose. The proposed algorithm retains the corrector step of the multiple-centrality-correction interior point algorithm

solving the iteration divergence problem due to the wrong corrector direction. In this algorithm

the predictor-corrector direction is selected as the affine direction for the centrality corrector

and the weighted corrector is selective to be added in the predictor corrector direction during each predictor-corrector step through pre-installed logic

thus further improving the convergence. Simulation results of an IEEE test system and a real power system are provided to verify the feasibility of the algorithm.