波动载荷下弓网动态接触电阻特性研究

在实际的列车运行过程中压力载荷是以正弦形式波动变化,波动载荷对弓网系统中的接触电阻特性有重要影响。文中利用销盘式高速载流摩擦磨损实验机模拟弓网系统中的压力波动状态,研究了波动载荷、滑动速度和接触电流对动态接触电阻特性的影响,结合表面形貌对其变化规律产生的原因进行了分析。结果表明:载流滑动接触且压力波动频率一定时,动态接触电阻随压力波动幅度的增大先减小后增大;压力波动幅度一定时,动态接触电阻随压力波动频率的增大而缓慢增大;波动载荷条件下,动态接触电阻随滑动速度的增大而逐渐增大,随接触电流的增大而逐渐减小。高温电弧和接触温升是导致动态接触电阻变化的主要原因。

Study on Dynamic Contact Resistance of Pantograph Catenary Under Fluctuating Load

In the actual train operation, the pressure load fluctuates in sine form,and the fluctuating load has an important influence on contact resistance characteristics in pantograph catenary system.In this paper, the pressure fluetuation in the pantograph catenary system is simulated by a pin disk high speed current borne friction and wear tester, the influence of different factors on the dynamic contact resistance is studied and combining with the surface morphology, the causes of its variation regulation are analyzed. The experimental results show that when the current carrying sliding contact and pressure fluctuation frequency are definitized, the dynamic contact resistance decreases first and then increases with the increase of pressure fluctuation range;when the pressure fluctuation range is definitized, the dynamic contact resistance increases slowly with the increase of pressure fluctuation frequency. Under the condition of fluctuating load,dynamic contact resistance increases with the increase of sliding velocity,decreases with the increase of contact current.High temperature arc and contact temperature rise are the main causes of dynamic contact resistance change.