Nowadays, there is a huge interest regarding the use of artificial intelligence techniques. From the associated methods, the current work is focusing on particle swarm optimization (PSO) study. The authors aim to present a synthesis regarding the PSO applications within the power system field. Two issues are addressed within the paper. Firstly, the PSO parameter tuning using mathematical test functions. Secondly, the conclusions are applied in case of optimal power flow (OPF) computing for small scale test power systems. For both issues the methodologies are presented, software tools have been developed. The research work is going to be continued having as a goal to develop a PSO based software designed for transmission network expansion (in case of complex power systems).