A power quality forecast assessment of Bin-zhou electrified railway based on PSASP

The asymmetry of electrified railway loads accessed to the power system would bring the harmonic waves and negative-sequence currents, giving rise to the distortion of voltage waves and the problems of power quality, such as the unbalance of the three-phase voltage. Combined with the project “Power quality assessment of Bin-zhou railway electrification reconstruction project of the traction substation”, this paper introduces a power quality forecast assessment method based on Power System Analysis Software Package (PSASP). Considering the railway load features, harmonic superposition characteristics and access way of traction stations, simulations are performed to analyze various power quality indexes of the point of common coupling (PCC) under different working conditions with traction loads station accessing to the system, then the power quality background test are performed for the substations of the traction station access point, the influence of electrified railway on the whole grid will be found according to the above two aspects. Results show that commutation by turns with traction stations accessing to the system has an offset effect on negative sequence current, and verify that the difference of traction load has various effects on the system.