摘要
为研究牵引机车中的高频谐波以及由此导致应力控制型电缆终端绝缘迅速劣化的问题,研究了牵引机车过分相时电网电压波形畸变率和谐波的变化,以及此高频谐波对电缆终端的影响。搭建了高频高压电缆老化实验平台,利用高频高压发生装置对电缆终端施加了不同频率的电压,使用红外热成像仪分析了高频谐波对不同类型电缆终端热点的影响。研究结果表明:牵引机车过分相时电网电压、电网电流波动比较明显,而且由此带来的谐波比较严重,随着谐波频率的不断增大,电缆终端局部形成电场高点并转换成阻性发热,阻性发热功率密度也增加,应力控制型电缆终端在局部的热点温升比几何型电缆终端表现得更加明显。谐波频率的增加会导致材料介电性能的降低,进而会引起电缆终端电场强度的增加,牵引机车适当加装高频滤波装置有助于延长其电气设备的使用寿命。
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.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2016年第11期3601-3606,共6页
High Voltage Engineering
关键词
牵引机车
高频谐波
电缆终端
红外热成像仪
阻性发热功率密度
热点温升
traction locomotive
high frequency harmonic
cable termination
infrared thermal image instrument
resistive thermal power density
hot-spot temperature rise
