Investigation of Power Factor Behavior in AC Railway System Based on Special Traction Transformers

Abstract

The single-phase traction load has essentially an unbalance characteristic at the Point of Common Coupling (PCC), which injects harmonic into the utility grid. In this paper, the effect of harmonic distortion and unbalance loading are investigated simultaneously for electrical railway systems. Special traction transformers (i.e. single-phase, V/V, Wye-Delta, Scott, and Le Blanc) are used between the utility grid and the traction load. For analysis, different defini-tions of power factors are considered, which are presented by IEEE Std.1459. The detailed simulation study is made with MATLAB/SIMULINK program to represent the impacts of harmonic components and unbalance loading on the power factor behavior in the Electrical Railway systems.