地铁供电系统对电网电能质量影响的仿真研究

Simulation Research on Influence of Metro Power Supply System on Grid Power Quality

城市轨道交通供电系统负荷不连续,变化较大,会引起电压和频率问题,整流机组含有大量的非线性器件,使得电网中产生大量的谐波,可能威胁到电网的安全稳定运行。基于PSCAD/EMTDC搭建了牵引站仿真模型,同时依据武汉轨道交通机场线的实际数据,建立了整个机场线仿真模型,并分析了公共连接点处谐波、电压偏差、电压波动与闪变、三相不平衡度、频率偏差等电能质量数据。仿真结果与理论分析基本一致,验证了所搭建模型的正确性和合理性。最后,对轨道交通机场线供电系统电能质量问题提出了相应的建议和措施。

The load of urban rail transit system power supply is not continuous, great variation and will cause the voltage and frequency issues. Rectifier unit contains a large number of nonlinear devices that produce large amounts of harmonies in power grid. As a precaution, it is necessary to analyze the power quality problems caused by rail transit in advance, and accordingly some appropriate preventive measures can be taken. Firstly, the paper establishes a simulation model of traction station by PSCAD/ EMTDC and a simulation model for the whole airport line based on the actual data of Wuhan rail transit airport line. Secondly, the paper analyzes the harmonic, voltage fluctuation and flicker, voltage deviation, three-phase imbalance degree and frequency deviation at the point of common coupling. The simulated data is consistent with the theoretical analysis data. The results show that the model is reliable and correct. Finally, the paper proposes reasonable suggestions and measures about the power quality problems of the metro power supply system of the airport line,