Experimental investigation on spectral characteristics of pantograph-catenary arc plasma

Pantograph-catenary arc plasma, with high temperature and high energy density, can severely threaten the electrical contact performance of pantograph-catenary system in high speed railway. In this paper, pantograph-catenary arc experiments were conducted based on arc simulative platform in laboratory. The characteristic of pantograph-catenary arc plasma was studied by spectral diagnosis method, and then the primary characteristic lines were recognized and classified. The excitation temperature, rotational temperature, vibrational temperature and electron density were also calculated, respectively. Meanwhile, the influence of input current on excitation temperature and electron density was analyzed. The results show that abundant copper, iron and CN B2∑+→X2∑+ characteristic lines would occur due to the intense erosion effects of pantograph-catenary arc plasma on copper wire and metal impregnated strips. In addition, it is found that the excitation temperature of pantograph-catenary arc plasma increases with the increase of current based on Boltzmann plot. The rotational temperature and vibrational temperature reach up to 6800 K and 9000 K respectively when the current is 30A, according to the theoretical calculation with the spectral line of CN B2∑+→X2∑+. Furthermore, the broadening mechanism of characteristic lines was discussed, and by CuI 521.82 nm characteristic line the increasing tendency of electron density with the input current was analyzed. © 2016, The editorial office of Transaction of China Electrotechnical Society. All right reserved.