A Novel Detection Method for Interface Defect Development of High-Speed Train Cable Terminal

As the weak link of the cable assembly, the internal insulation structure of the cable terminal is complex, the installation requirements are high, and the operating environment is complex, which is prone to external interference and insulation failure. However, the existing detection means of the cable terminal of the rolling stock is complicated, expensive, vulnerable to field noise interference and inefficient detection. In this study, a new method for diagnosis of cable termination insulation status by measuring the field strength along the cable termination surface is proposed. The characteristics of axial electric field distribution of defective cable terminals are studied by using multi-physical field simulation method to realize the degree of axial development of faulty cable terminal. The electric field sensor was used to measure the surface field intensity distribution of cable terminals with different degrees of interface defects, and the electric field intensity distribution law of cable terminals with different degrees of defects is obtained. The distribution of the interquartile range and variance of the electric field intensity along the cable terminal is analyzed. The results show that the greater the interface defect, the greater the interquartile range and variance of the electric field intensity along the cable terminal. Therefore, the development degree of interface defects can be judged by testing the surface electric field intensity of cable terminal.