This paper describes the methodology adopted for the optimal var dispatch (OVD) integrating a particle swarm optimization (PSO) algorithm and the interior point method (IPM). The proposed hybrid method can be mainly divided in two parts. The first part is to solve the OVD with the IPM based on the logarithmic- barrier primaldual algorithm (LB-PDA), for non linear programming (NLP) by relaxing the discrete variables. In the second part, the PSO algorithm is used to solve the discrete variables with the continuous variables being fixed, whereas the IPM solves the continuous optimization with the discrete variables being constant. The optimal solution can be obtained by solving the two sub-problems alternately. Numerical simulation on the Western Algerian power system illustrate this proposed hybrid method.

Keywords: Interior point method (IPM), Particle swarm optimization (PSO), Optimal var dispatch(OVD).