Study of Power Quality on the Interaction of Wind Farm and Electric Railway

Based on a real engineering project, by means of electro-magnetic transient simulation software EMTP-RV, a detailed simulation of the largest wind farm in Hubei Province (Xianghe Wind Farm) has been modeled, and an electric railway Huji traction station with locomotive load model is connected to the wind farm on the same 110kV bus. Multiple operating conditions such as the grid independently carrying load, wind farm connecting to the grid separately, electric railway load connecting to the grid separately, wind farm with different wind speed and different electric railway load simultaneously connecting to the same substation 110kV bus, are simulated and analyzed. A power quality calculation template was developed, and the corresponding power quality indexes were calculated. The simulation results show that the wind farm and electric railway load connected to the same bus will deteriorate the operating conditions of the grid PCC, and cause extremely voltage fluctuation and harmonic injection. Combining with field conditions, a number of improvement advises are put forward from the voltage fluctuation and the power oscillation phenomenon revealed by the simulation, such as: a reasonable scheduling of wind farm active reactive power output, adding harmonic compensation device at electric traction station, set up SVG reactive power compensation automatic control system at 110kV substation. After that, the improved PCC power quality will fulfill the national standards.