基于双弓受流动力学的弓网接触电弧分布

Arc distribution in pantograph-catenary contact based on double-pantograph current collection dynamics

针对双弓受流情况下发生的电弧问题,基于经典电接触理论分析了弓网接触面微观结构与弓网接触电弧的产生机理,提出了接触电弧发生率算法;考虑双弓受流条件下接触网波动传播规律分析了双弓耦合系统动力学模型,建立接触网有限元模型与受电弓多体动力学模型,获取不同后弓静态抬升力下的前后弓接触力;结合接触电弧发生率算法与获取的前后弓接触力,计算多工况下前后弓接触电弧发生率,分析其在对应的接触力下接触电弧分布规律,并提出减小接触电弧发生率的措施。研究结果表明:在前弓上发生的接触电弧发生率远小于后弓上的概率,前弓均值仅为后弓的32%;后弓静态抬升力的变化对前弓接触电弧发生率影响很小,4种工况下前弓接触电弧发生率均在1.5×10^(-3)~5.0×10^(-3)内波动,无明显变化规律;后弓接触电弧发生率随后弓静态抬升力的增大显著减小,随着抬升力从55 N升高至85 N,后弓接触电弧发生率平均降低了42%;前弓上接触电弧发生次数随接触力的变化无明显变化规律,后弓静态抬升力越大其分布越均匀;后弓上接触电弧发生次数分布随接触力增大而减少,主要分布于接触力低值区间内;接触力在70~80 N以及大于170 N时可有效抑制前弓接触电弧的发生,接触力大于70 N时可以有效抑制后弓接触电弧的发生。

In view of the arc problem during double-pantograph current collection,the microstructure of the pantograph-catenary contact surface was analyzed based on the classical electrical contact theory,and the mechanism of arc occurrence in the pantograph-catenary contact state was discussed.The probability algorithm of arc occurrence in the pantograph-catenary contact was proposed,and the dynamics model of the double-pantograph coupling system was analyzed by considering the fluctuation and propagation laws of the catenary under the double-pantograph current collection.A finite element model of the catenary and a multi-body dynamics model of the pantograph were established to obtain the contact forces on the leading and trailing pantographs under different static lifting forces of trailing pantograph.According to the contact arc probability algorithm and the obtained contact forces,the probabilities of contact arc occurrence on the leading and trailing pantographs under multiple working conditions were calculated,the distribution law of the contact arc under the corresponding contact force was analyzed,and the measures to reduce the probability of contact arc occurrence were proposed.Research results show that the contact arc occurrence probability on the leading pantograph is much smaller than that on the trailing pantograph,its average value is only 32%of the latter average value.The change of static lifting force of the trailing pantograph has little impact on the contact arc occurrence probability on the leading pantograph.The contact arc occurrence probability on the leading pantograph fluctuates between 1.5×10-3 and 5.0×10-3 under four working conditions,and there is no obvious change rule.The contact arc occurrence probability on the tailing pantograph decreases as the static lifting force of the tailing pantograph increases.The average contact arc occurrence probability on the trailing pantograph reduces by 42%as the lifting force increases from 55 N to 85 N.There is no obvious law of contact arc occurrence on the leading pantograph with the distribution of contact force,and the higher static lifting force of the tailing pantograph makes the distribution more uniform.The distribution of the contact arc occurrence probability on the tailing pantograph decreases with the increase of the contact force,and the probability mainly distributes in the low-value range of the contact force.Controlling the contact force within the range of 70-80 N and greater than 170 N can effectively suppress the arc occurrence on the leading pantograph,and controlling the contact pressure more than 70 N can effectively suppress the arc occurrence on the trailing pantograph.