Analysis and Treatment of Harmonic in Power Network with Railway based on ETAP Software

Due to the development towards high-speed, high-capacity, high-density networking of high-speed railway, harmonic problems caused by high-speed locomotives are getting more and more serious, which has been a great threat to the safety and stability of power system operation. In this study, the influence of harmonic in power network with railway is analyzed and the treatment measures are studied. At first, this paper makes an evaluation on the impacts on power system with railway both in theory and the data measured by PQView. Then, it makes an introduction to the power system analysis software ETAP, and highlights on its typical function in power quality problems especially, such as harmonic analysis, capacitor best position analysis, unbalance load flow analysis and etc. Then, the over-standard problem of bus harmonic voltage at three sides of the transformer and harmonic current main feeders from 110kV bus in certain 220kV substation are analyzed by using the PQ Analyze software. By comparing the special field test data and simulation data based on ETAP, harmonic pollution is analyzed. Besides, the treatment methods are proposed which are that single tuned filter should be installed. ETAP simulation results shows that the treatments has obvious effect, and the harmonic voltage content are reduced within the limit range, which achieves the purpose of the harmonic mitigation, and provides a theoretical reference for the improvement of the power quality in power network.