Calculation of Characteristic Parameters and Research of Fault Diagnosis for Aircraft Wires Existed Insulation Defects

摘要

Characteristic impedance and reflection coefficients of different insulation faults have been calculated in single core lossy aircraft wires. According to these parameters and the mathematic model of insulation frayed wire, transmissions are simulated for step waves of different rise time. A fast leading edge rectangular wave generator is implemented to detect small insulation faults, then wavelet methods are used to eliminate noise in received wave and ascertain the starting time of peak corresponded to fault. The results show that these methods contribute to detecting small insulation faults, and improving the accuracy of faults location.