Test And Evaluation Of Insulation Characteristics Of Typical Electrical Components In Alpine Plateau Environment

As a common failure mode,insulation failure often has a fatal impact on electrical components in the equipment,especially in harsh natural environment such as alpine plateau regions.It is very easy for insulation aging to lead to the performance degradatation of electrical components,while insulation breakdown will have irretrievable consequences on electrical components,circuit systems and even the whole equipment due to different degrees,which seriously threatens the safety of electrical equipments and personnel.With the support of National Key R&D Program of the 13 th Five-Year Project,this paper has carried out the research on insulation characteristics test and evaluation of typical electrical components in alpine plateau environment,and the purpose of this paper is to provide reference and technical support for the reasonable selection,evaluation and analysis of key components of the equipments serving in alpine plateau environment as well as the safe and stable operation of electrical systems.The main contents of this paper are as follows:1.The insulation breakdown of electrical components under low air pressure,the insulation aging under high altitude environment and the evaluation methods of insulation characteristics were reviewed and analyzed.Apart from that,the contents that could be further studied in the current insulation characteristics test and evalation research were summarized as well.2.The electromagnetic relays were chosen as the typical electrical component,and the insulation breakdown test based on the low pressure and low temperature environment was carried out by using the principle of orthogonal experiment.The regression equation of AC Withstand Voltage and Air Pressure of the electromagnetic relays in alpine plateau environment was obtained by the analysis of test data.Apart from that,the insulation breakdown failure mechanism of the electromagnetic relays under low air pressure was revealed.3.The cables used for equipment were selected as the typical electrical component,and the insulation aging test based on strong solar radiation and large temperature difference environment was carried out.According to the test results,the changes of electrical performance,mechanical performance and exterior appearance of the cables used for equipment were obtained,and the life prediction model of cables in specific environmental profile in alpine plateau regions was established.At the same time,the thermal performance of insulation aging was also analyzed by environmental simulation,and the fitting equation of thermal indexes about radiation time was obtained.Insulation aging failure mechanism under strong radiation was revealed as well.4.A comprehensive evaluation method of insulation characteristics of typical electrical components in alpine plateau environment was put forward,and an example was analyzed by taking the relevant data of insulation aging test into consideration.The calculation results could quantitatively reflect the changes of insulation characteristics of electrical components in alpine plateau environment.