Research And Implementation Of Aviation Arc Fault Detection Device

With the development of electrical technology and the emergence of multi electric all electric aircraft,the number of airborne electrical equipment has increased significantly,the aircraft power distribution system has become more complex,and the number of cables has also increased.Due to the limited space of the fuselage,different types of cables inevitably cross stack.Working in the working environment of high radiation,strong oxidation and vibration for a long time,the cables are prone to aging,damage and arc fault.Because of its small current amplitude and short duration,the series arc fault is difficult to be detected by the commonly used circuit protection device in the aircraft and cannot be protected in time and effectively.Therefore,it is very important to study the characteristics of series arc fault,find out the characteristics that can effectively represent the fault information,formulate accurate identification strategy,and design aviation arc fault detection device to realize series arc fault identification,which is of great practical significance for improving the safe and reliable operation of aircraft.In this paper,the series arc fault is selected as the main research object.Referring to the existing arc fault detection standards at home and abroad,the carbonization path test,point contact test and vibration test are carried out under different working conditions.With the aid of anti-interference experiment,the purpose is to improve the effectiveness of arc fault feature extraction and the reliability of detection device,including crosstalk interference experiment and feedback immune experiment.Based on the characteristic changes of normal and arc fault current signals collected by experiments,the characteristic values which can effectively reflect the amplitude change,distortion and high-frequency component change of current waveform are extracted by using the time-domain and frequency-domain characteristic calculation methods to represent the arc fault information.Analyze the applicability of each characteristic quantity to different experimental loads,combine them reasonably,construct multi degree characteristic vector,and make arc fault identification strategy.This paper analyzes the general requirements of Aviation series arc fault detection,determines the type of operation processing chip used in the detection device and the model of other key components,designs the hardware circuit and software flow of each functional module of the detection device,compiles data acquisition,analysis and arc fault determination algorithm,implants the arc fault detection prototype,and completes the preparation of the prototype.In order to test the arc fault detection ability and reliability of the prototype,a series arc fault test and anti-interference test are carried out.The test results show that the aviation arc fault detection prototype designed in this paper can detect the arc fault in pure resistive load and resistive capacitive load quickly and accurately;for resistive inductive load and nonlinear load,the fault identification can also be completed within the standard time,but the time used is longer and the accuracy is slightly lower;In addition,when the circuit under test is disturbed,the detection device can still work normally.