Evaluation On Performance And Research On Application Of New Grounding Material

In power system,grounding network provides channels for fault current and lightning current to rapid discharge,and plays a balanced role in the vicinity of the potential equalizer.Grounding network is an important guarantee for person and equipment safety.Traditional ground material was often seriously corroded,which cost a lot.Thus,many new ground materials were developed to deal with this problem.In order to provide guidance for the selection and utilization of new grounding materials,it is necessary to make the actual construction of the substation grounding system engineering more feasible and normative.Therefore,it is necessary to evaluate the electrical properties,corrosion resistances and economical properties of those new grounding materials.This paper studied the current situation of the utilization of the grounded materials in China,and analyzed the advantages and disadvantages of the commonly used copper-plated steel,nanocomposites and zinc-magnesium alloys.Furthermore,the paper figured out the physical and chemical parameters of the flexible graphite.Additionally,the advantages and disadvantages of flexible graphite were compared in this paper.In this paper,the author studied the metal corrosion and protection of metal grounding materials.Thereafter,the role of soil type,water content and groundwater level,soil resistivity and soluble ion content,soil pH and microorganisms in soil corrosion were analyzed.The corrosion of carbon steel can be divided into three types: disturbed comprehensive corrosion,disturbed local corrosion and undisturbed corrosion.This paper forwarded the protective measures of organic coating corrosion control and catholic protection.Also,this paper analyzed the performance of flexible graphite materials,and tested the mechanical properties of graphite materials,resistivity,permeability,temperature tolerance,continuous power frequency current tolerance.Through experiment,the paper calculated the thermal stability coefficient of flexible graphite.In addition,we studied the change of impact coefficient under the action of graphite current.Furthermore,the economic analysis was conducted on various type of grounding material.This paper studied the field application of flexible graphite grounding material,then measured the field resistance and resistivity.Thereafter,the obtained data were analyzed on the field of flexible graphite grounding in the 500 kV YongQi line of INNNER MONGOLIA EHV Electric Power Branch.