AT供电系统接触网在线防冰电流的决策与控制

为了保障行车安全,消除接触网覆冰,针对电气化铁路AT(autotransformer)供电系统特殊的长回路和短回路结构,建立防冰系统投入后AT供电系统的电路模型.用该模型分析各AT段内防冰电流和负载电流的分布,得到保障全线防冰所需电流值;根据防冰电流与供电臂末端电压的关系,得出了牵引网压允许的防冰电流值;在此基础上,制定了以温度为目标的在线防冰电流决策流程.以某AT供电区段为例,结合实测负荷数据进行了仿真,结果表明:投入的防冰电流值至少为接触网临界防冰电流值的2倍,才能使接触线表面温度维持在0 ℃以上. 

Decision and Control of Catenary On-Line Anti-icing Current in Autotransformer Power Supply System

In order to prevent icing on catenaries and ensure trains' normal operation on electrified railways, a circuit model for the autotransformer (AT) power supply system during anti-icing period was built according to the special structure of long and short loops of the AT power supply system. This model was then used to deduce the comprehensive distribution of the anti-icing current and load current in each AT section, and the current that can prevent icing on the whole line was calculated. After analyzing the relationship between the catenary anti-icing current and the terminal voltage of the power supply arm, the anti-icing current value allowed by the voltage of traction electric network was obtained. On this basis, the decision flow of the on-line anti-icing current was proposed, aiming at maintaining the temperature of contact wire. In addition, simulations were carried out for an AT section, and the simulation results were compared with the measured load data. The results show that the anti-icing current of catenary should be 2 times the critical anti-icing current at least, such that the temperature of contact wire can maintain above 0 ℃ with anti-icing current.