Abstract:In order to study the degradation of oil-mpregnated insulation paper by microorganisms, the mass ratio of oil-aper sample is about 10∶1, and the comparative samples are pretreated by natural pollination, artificial inoculation and high temperature sterilization. Metal aluminum is added into samples 3 and 4, and metal copper is added into sample 5. The biodegradation test is carried out at 15~35 ℃ which is the most suitable ambient temperature. The products of biodegradable oil-mpregnated insulation paper and the change trend of gas content are analyzed by high performance liquid chromatography, gas chromatography and other instruments, and the changes of microstructure of oil-mpregnated insulation paper before and after the test are observed by scanning electron microscope (SEM). The test results show that after the biodegradation, characteristic products are generated such as furfural, CO and CO2, but the structure of cellulose of insulation paper has been damaged. The contents of CO and CO2 increases first then decreases, and then increases, and finally it tends towards stability with microbial degradation. The SEM shows that the crystals and amorphous structures of cellulose have changed, the crystalline region of cellulose surface becomes rough, loose and fractured, the amorphous region occurs small pores, and the crystalline region is not closely connected with the amorphous region. Characteristic products of degradation and the variation characteristics of their gas product are important reference basis for distinguishing whether microbial contamination occurs in insulation paper of non-perating power equipment.