典型敷设条件下电力电缆线路运行振动特征值的测量试验

Measurement of Vibration Characteristics of Power Cable Line Under Typical Laying Conditions

为测量和分析电力电缆线路运行振动特征,分析由振动所引起的电缆线路运行缺陷的原因,在分析电缆线路的电磁力计算及振动力学特性基础上,将加速度传感器安装在电缆线路上,测量了施加电压和电流条件下的振动频率特征及振幅与电压和电流变化的对应关系,并测量了在不同敷设方式条件下的振幅变化。研究结果表明:电缆线路上的电压值和电流值越大则所产生的振幅越大;相同电压和电流条件下,隧道条件下的电缆振幅大于直埋敷设条件下的电缆振幅;终端和接头的振幅大于电缆本体振幅。根据获得的振幅与电压值和电流值的对应关系、振幅与敷设方式的对应关系,提出了对高电压大电流电缆线路应在蛇行敷设电缆、电缆终端及接头的铅封等位置处增加防振垫等措施,避免局部受力。研究成果可以为进一步分析不同敷设方式下高压电缆线路运行振动的影响、制定针对性的运维策略及构建振动分析模型提供参考。

In order to measure and analyze the characteristics of power cable lines and hence understand the mechanism of cable defects caused by vibration, we analyzed cable lines through electromagnetic force calculation and mechanical vibration discussion, and installed acceleration sensors on cable lines with load to measure the correspondence of vibration frequency and vibration amplitude to voltage and current, as well as the variation of vibration amplitude under different laying setups. The measurement results show that the vibration amplitude increases with both the applied voltage and current, and the vibration amplitude of a cable line carrying the same current and voltage is higher in tunnel setup than in direct burial setup, and it is higher at the terminals and joints than along the cable body. According to the acquired measurement data, we proposed to protect high-voltage large-load cables from local stress concentration through adding vibration-proof pads to some key parts of the cables, including the cable parts in zigzag setup and lead seals of terminals joints.