计及回流系统设备行为过程的钢轨电位动态仿真

Dynamic Simulation of Rail Potential Considering the Equipment Behavior Process of Recirculation System

为控制杂散电流与钢轨电位,钢轨电位限制装置(OVPD)、连接装置(CD)等设备广泛运用于轨道交通运营线路,直流牵引供电系统中的钢轨电位异常问题越来越引起重视。回流系统设备的状态切换会造成钢轨电位动态分布发生显著变化。建立回流系统等效电路模型时不应只考虑正线,也应当考虑段场以及回流设备的行为过程。为此,该文建立OVPD和段场等效电路的通用模型,并提出计及回流设备行为过程的直流牵引供电计算方法。以某实际地铁工程为例,对运营线路进行仿真,采用该文算法的计算结果与实际工程中的钢轨电位变化过程更加吻合。在此基础上,讨论分析正线与段场之间的相互影响,结果表明,段场单向导通装置(UCD)的设置无法避免正线与段场之间的相互影响;段场钢轨直接接地更易恶化正线钢轨电位,相较于正线与段场之间采用阻断式连接装置(BCD)的情况下,正线钢轨电位Umax和Umin分别提高34.46%和降低33.97%。

The abnormal rail potential in the DC traction power supply system has attracted more and more attention.In order to control the stray current and rail potential,the rail potential limiter over-voltage protection device(OVPD),the connection device connection device(CD)and other equipment are widely used in operating lines.The dynamic distribution of rail potential will be significantly changed with the state switching of the equipment.When establishing the equivalent circuit model of the recirculation system,not only the main line should be considered,but also the parking lot/depot and the behavior of recirculation equipment.To this end,this paper established a general model of parking lot/depot equivalent circuit and OVPD.And a DC traction power supply calculation method is proposed considering the behavior of the recirculation devices.Taking an actual subway project as a simulation example,the calculation results with the proposed algorithm are more consistent with the rail potential change process in the actual project.On this basis,the interaction between the main line and the parking lot/depot was discussed and analyzed.The results show that the setting of the unidirectional connection device(UCD)of the parking lot/depot cannot avoid the interaction between the main line and the parking lot/depot,and the direct grounding of rail in parking lot/depot is more likely to deteriorate the rail potential of the main line.Compared with the case of a blocking connection device(BCD)between the main line and parking lot/depot,the rail potential Umax and Umin in main increased by 34.46%and decreased by 33.97%,respectively.