Harmonic Effect And Control Of Miaolian High Speed Railway Traction Station On Shaoguan Power Grid

With the continuous improvement of EMU train speed and the continuous improvement of railway network,electrified railway transportation has become the main means of transportation in China,which is widely used for its advantages of fast speed,heavy load,high energy efficiency and no pollution to the environment.However,with the development of electrified railway transportation,it also brings about the corresponding power quality problem.Because EMU trains obtain current from the power grid as a single-phase load,it will produce harmonic current during operation.These harmonic currents flow to the regional power grid through traction substations.With the construction and operation of more and more electrified railways in China,people pay more and more attention to the harmonic problems which affect the safety and reliability of the power network during the train running of the electrified railway EMU.In view of the above situation,this paper studies the influence and treatment of the harmonics produced by the Miao Lian traction station in Shaoguan area on Shaoguan Power Grid:(1)Analysis of the current power supply mode of traction network in Shaoguan area and the transmission mode of EMU train: single-phase power frequency AC power supply,autotransformer(Auto-Transformer,);and AT)the characteristics of the power supply mode and the "AC-DC-AC" transmission mode,and electrical simulation model,And verify the correctness of the model.According to the harmonic data obtained,the harmonics generated by traction power supply system are mainly concentrated in 3,5,7and100 harmonics,The 3rd,5th,7th harmonics are the lower harmonics brought by the system and traction load,About 100 harmonics are characteristic harmonics injected by traction load of EMU trains,Provide data for harmonic regulation.(2)Through the power quality data measured at Tongji station and Furong station,the harmonic is injected into the power system,and the influence of the harmonic on Shaoguan power network is analyzed.(3)Combined with the structure of passive filter and active filter,their respective characteristics are analyzed.According to the characteristics of high performance-price ratio and operation under bad conditions,a passive filter device is designed at the low-voltage side of Miao Lian traction station according to the minimum capacitance method.The device includes 3 filter branches,5 filter branches,7 filter branches and high pass filter branches.(4)The passive filtering device is added to the traction power network model,and the harmonics in the simulation results are basically filtered out,which indicates that the harmonic control effect of the passive filtering system is obvious,which provides a reference for Shaoguan power network to control harmonics.