Improvement of Harmonic Measurement and Test Procedures Considering Inflow on the Power Source at the Railway Substation

AC substation power quality tests are evaluated by measuring harmonics and voltage unbalanced under driving conditions of electric trains. Harmonics are measured up to the fundamental and 49th harmonics by connecting a power analyzer to the 154㎸ side busbars at the substation. During the test operation of the EMU260 and EL8500 on the newly built Daegu Line of the Yeongcheon Railway Substation, it was evaluated that 27th harmonic voltage% exceeded the standard in the harmonic measurement. In order to analyze the cause of exceeding the standard, all load CB on the Daegu Line were opened and measured, and it was confirmed that harmonic waves from power sources were already exceeding the standard. In this paper, when measuring the harmonic of a new electric railway substation, it is measured by considering the inflow from the power supply, the reasons why the standards should be judged or not and the improvement of the power quality test evaluation criteria were presented.