城轨供电系统功率分配影响下钢轨电位异常升高研究

城市轨道交通直流牵引供电系统钢轨电位升高问题已成为线路运行安全的难题,其异常升高机理及分布规律尚待阐明,基于单供电区间单列车的分析方法与实际线路多列车并列运行工况差距较大。为研究城轨多列车多变电所并列运行下系统功率分配对钢轨电位异常升高的影响,建立城轨供电系统平行多导体模型,并针对回流系统模型等效及参数计算进行分析;基于有向图理论建立城轨供电系统功率分配计算方法,进行多节点功率计算;基于实际城轨线路参数,仿真计算系统多列车动态运行时的功率分配及钢轨电位,结合具体时刻分析功率分配对钢轨电位的影响。分析结果表明,钢轨电位受系统功率分配影响较大,优化系统功率分配可有效控制系统钢轨电位异常升高问题。

Effect of Power Distribution on Abnormal Rise of Rail Potential in Urban Rail Power Supply System

Abnormal rise of rail potential in DC traction power supply system of urban rail transit has become a problem of operation safety. The mechanism and distribution of abnormal rail potential need to be clarified. The mode that single train operating in single power supply section is far from the mode that multi-train running in parallel on the actual line. In order to analyze the effect of power distribution on abnormal rail potential under parallel operation of multi-train and multi-substation in urban railway, the parallel multi-conductor model of traction power supply system is established. The model equivalence and parameter calculation of the reflux system are analyzed. Then, a power allocation calculation method based on directed graph theory for urban railway power supply system is established, and the power distribution is calculated. Based on the actual parameters of urban railway line, the power distribution and rail potential with multi-train operating dynamically in the system are simulated and calculated. The effect of power distribution on rail potential is analyzed at specific time. Results show that rail potential is greatly affected by the power allocation of the system. Optimizing the power distribution of the system can effectively control the abnormal increase of rail potential.