Research On High-frequency Signal Attenuation And Compensation Of Arc Fault Based On Double Conductor Transmission Line

Arc fault detection technology is particularly critical to prevent the occurrence of arc electrical fire.At present,the methods of arc fault detection mainly focus on high frequency and low frequency characteristics.The application of high frequency characteristics is more reliable than the low frequency characteristics in some scenarios.In the practical application,the high frequency signals detected by sensors often attenuate due to various suppression conditions.In order to solve this problem,according to the test requirements of the Chinese standard on the attenuation of high frequency signal in line transmission suppression and capacitance filtering suppression,this paper studies and proposes a method to correct the attenuation of high frequency voltage signal of arc fault,to improve the accuracy of arc fault detection.Starting from three aspects: high frequency characteristic band of arc fault signal,acquisition of distribution parameters of transmission line and attenuation characteristics of signal under different conditions,the original signal output from sensor is corrected by a compensation link.The main research work and achievements are as follows:1.The mechanism of generating high frequency signal when arc fault occurs is expounded from the perspectives of signal discontinuity and electromagnetic induction,and analysis the cause of attenuation of high frequency signal.2.Distribution parameters of double conductor transmission lines are studied.The parameters of transmission lines are obtained by theoretical calculation model and practical measurement.Error analysis shows that they are basically identical in a specific frequency range.3.Based on the characteristic frequency band and the suppression condition of high frequency signal,dynamic response curve of high frequency signal attenuation with different frequency components are studied,and the corresponding compensator is designed.4.Under the conditions of line suppression and capacitance filtering suppression,the comparison of the original and the corrected high frequency signals of arc fault with different line diameters and different load types is carried out.The results show that the designed compensator can correct the high frequency signals of arc fault and widen the frequency band of the signals to a certain extent.It is of great significance to improve the accuracy of arc fault detection.