To investigate high frequency harmonics in traction locomotives and its fast degraded problems of insulation for stress control type cable terminations

this paper discusses the changes of the distortion rate of voltage and the harmonics in power grid when the traction locomotives are passing neutral section

and the effect of high frequency harmonics on cable termination is also discussed. The experimental setup of high frequency and high voltage aging is installed

and the high voltage is applied to the cable terminations with the different frequencies

and an infrared thermal image instrument is used to analyze the effects of high frequencies on the hot spots for the different cable terminations. According to the results

when the locomotive is passing neutral section

the fluctuations of voltage and current in power grid are noticeable

which can result in severe harmonics. With the increase in the harmonic frequency

cable termination forms the higher electric field on the spot

which can transform resistive heating. For this reason

the resistive thermal power density also increases with the increase in frequency

and the temperature rise of hot spot on the stress control type cable termination is much higher than that of geometric control type cable termination. Increase of harmonic frequency will lead to degradation of the dielectric performance

and it will cause the increase of electric field strength cable termination

installing properly high frequency filter devices for traction locomotives contributes to prolong service life of that electrical equipment.