Study on Power Quality Evaluation of Traction Power Supply System of High-speed Railway

Abstract

With the continuous development and progress of China's high-speed railway system, the power supply of high-speed railway has become an important load of the power system. The introduction of large load will bring certain voltage fluctuation, harmonic interference and other random problems to the power system. In this paper, the positive sequence, negative sequence and zero sequence component models of current and voltage are established to solve the problem of equivalent modeling for power quality assessment of high-speed railway power supply system. Firstly, the positive sequence, negative sequence and zero sequence component models of current and voltage based on symmetric component method are established. Through Fourier transform, the phase Angle of fundamental wave is solved, and the positive sequence, negative sequence, zero sequence component, sequence component diagram and current spectrum diagram of current and voltage under three actual working conditions are obtained Through the analysis of the whole train operation process, the amplitude graphs of the positive sequence, negative sequence and zero sequence components of the current and the curves of the third harmonic possession with time are obtained by using the above methods.