【目的】为了确保线缆回路电气连接可靠性,提出一种基于多幅值脉冲电流的电气虚接故障诊断方法。【方法】首先,通过有限元仿真分析电连接在正常和虚接状态下的接触电阻随温度和接触面积等关键参数的变化规律。然后,使用研制的电连接可靠性检测装置施加不同幅值的脉冲电流,测量电连接在正常和虚接状态下的接触电阻和温度,得到电接触电阻随脉冲电流幅值的变化曲线。最后,建立接触电阻与电流的数学模型,结合一阶导数和二阶导数分析,提出了一种基于导数的电气虚接故障判据。【结果】仿真和试验结果表明,本文所提诊断方法能够有效诊断电气虚接故障,并提高电气连接可靠性。【结论】本文所提基于导数的故障判据为电气虚接诊断提供了新思路,具有实际应用价值。

[Objective] To ensure the reliability of electrical connections in cable circuits, this paper proposes a method for diagnosing loose electrical contact faults based on multi-amplitude pulse currents. [Methods] Firstly, the variation of contact resistance with key parameters such as temperature and contact area was analyzed through finite element simulation under both normal and loose contact states. Then, a self-developed electrical connection reliability testing device was used to apply pulse currents of different amplitudes, and the contact resistance and temperature were measured under normal and loose contact states, obtaining the variation curve of contact resistance with pulse current amplitude. Finally, a mathematical model of the relationship between contact resistance and current was established, and a derivative-based fault criterion for loose electrical contact was proposed by analyzing the first and second derivatives. [Results] The simulation and experimental results demonstrated that the proposed diagnostic method effectively identified loose electrical contact faults and improved the reliability of electrical connections. [Conclusion] The proposed derivative-based fault criterion provides a novel approach for diagnosing loose electrical contact faults, demonstrating practical application value.

辽宁省教育厅项目（LJKFZ20220190）