Research On Cable Burning Mechanism Caused By Power Harmonics

With the popularization and application of power cables, people are graduallyshowing solicitude for fire accidents caused by the cable fault. Harmonics has beenfocused by domestic and foreign scholars because it has been become major hazards ofpower environmental pollution. Power cable is as the object of study in this paper, it isspecific studies the power harmonic lead to the cable thermal breakdown mechanism ofaging process. First, the harmonics harm is studied and analyzed to the cable line in thepower network. It completes the harmonic impedance of the cable model and in-depthstudies of the cable line harmonic amplification mechanism and the application of casestudy of mining grade XLPE cable6kV maximum current carryingcapacity.Second,harmonic current amplification is simulated by using Matlab in thecable lines. Harmonic current amplification will not only increase the line impedanceand power loss, but increase the cable line load currents. In order to study the change oftemperature caused by harmonic current in XLPE cable, it establishes a finite elementanalysis model by use of AutoCAD, MagNet and ThermNet and adopts co-simulationmethod to analyze the change of cable lines temperature under harmonic hazards. Thesimulation results show that increase of harmonic content will result in the cable linestemperature rise. It is the higher harmonic frequency, the higher temperature in the cablelines.From the harmonic content to analysis, if addition of the same harmonic content, itwill lead to the high temperature in the cable lines. From the harmonic frequency toanalysis, the different kinds of harmonic frequencies will lead to high temperature withincreasing the harmonic frequency.