飞机电缆管状屏蔽层损伤转移阻抗计算分析

Calculation and Analysis of Transfer Impedance of Damaged Tubular Shields of Aircraft Cables

针对飞机电缆屏蔽层损伤影响屏蔽效能从而危及飞行安全的问题,研究机载管状屏蔽电缆屏蔽层发生长矩形损伤时转移阻抗的变化规律。首先,基于转移阻抗理论分析理想状态管状屏蔽电缆的抗干扰特性,并应用算例进行分析验证;其次,根据管状屏蔽层结构特点,应用电磁耦合理论推导出发生长矩形损伤时屏蔽层的转移阻抗解析模型;最后,应用算例分析不同损伤参数对转移阻抗影响的变化规律。结论表明,管状屏蔽层电缆发生长矩形损伤后屏蔽层转移阻抗的大小受损伤尺寸、损伤角度和干扰电磁波频率影响。研究结论可为制订电缆屏蔽层损伤的相关标准提供理论依据。

To address the problem of damage to the shields of aircraft cables affecting shielding efficiency and thus endangering flight safety,this paper studied the changing law of transfer impedance when long-rectangular damage occurred in the shielding layers of airborne tubular shielded cables. First,anti-interference properties of tubular shielded cables under ideal conditions were analyzed on the basis of transfer impedance theory and verified by an example;second,according to the structural characteristics of tubular shields,an analytical model of transfer impedance in the event of long-rectangular damage was derived by applying the electromagnetic coupling theory;finally,an example was used to analyze the change of the effect of different damage parameters on the transfer impedance. The conclusion shows that the transfer impedance of shielding layers in the event of long-rectangular damage is affected by the size and angle of the damage and by the frequency of interfering electromagnetic waves,which provides a theoretical basis for the development of standards relating to cable shield damage.