中文摘要：

目前多条电气化铁道出现了低频率的网压振荡、波动现象,造成了机车的牵引封锁。机车–牵引网（简称车网）互联系统低频网压振荡具有很强的不可预见性,利用阻抗分析法对低频网压振荡问题进行分析,并基于Matlab/Simulink仿真平台建立了HXD2B型电力机车与牵引网的联合仿真模型,再现了牵引供电低频网压振荡现象。通过与实测波形对比,验证了模型的正确性。在车网联合仿真模型的基础上,分析和讨论了牵引网长度、牵引变压器接线方式、机车负载情况及机车控制参数对低频网压振荡的影响规律。仿真结果表明,减小牵引供电系统阻抗（改变牵引网长度、牵引变压器接线方式）或增大机车系统阻抗（改变机车负载情况、机车控制参数）均能抑制低频网压振荡现象。

英文摘要：

Recently, low frequency voltage oscillation and fluctuation appeared in a number of electrified railways, leading to train traction blockade. Low frequency voltage oscillation in integrated train-catenary system has strong unpredictability. In this paper, low frequency voltage oscillation was analyzed with impedance-based method. Integrated simulation model of HXD2 B electric train and traction network was built on Matlab/Simulink, and low frequency voltage oscillation in traction power supply system wasreproduced. In comparison with measured waveforms, accuracy of the proposed model was verified. On this basis, different factors affecting low frequency voltage oscillation（e.g. catenary length, connection mode of traction transformer, traction load and control parameters of train） were analyzed and discussed. Simulation results showed that both reducing traction power supply system impedance（including catenary length, connection mode of traction transformer） and increasing traction system impedance（including traction load and control parameters of train） can suppress low frequency voltage oscillation.