Research On Security Vulnerability Assessment Method Of Petrochemical Plants

In recent years,because of the defects to the grounding device,the electrical equipment is damaged,causing a major accident,and accidents that cause economic losses occur from time to time.For example,accidents caused by poor grounding occurred in Guangxi Heshan Power Plant,Hubei Qianjiang Substation,and Sichuan Huayingshan Power Plant.These accidents led to major accidents which defects in grounding devices have caused people to attach importance to grounding devices.The grounding resistance value is an important parameter to confirm the validity of the grounding device and to judge whether the grounding system meets the design requirements.It is a very important technical index for the grounding device.Because of the coefficient values in the relative calculation formula,especially the value of the seasonal coefficient,the inhomogeneity of soil resistivity and the inaccurate measurement of soil resistivity,the calculation value of grounding resistance in grounding device can only be used as a reference.In order to better reflect the operation status of the grounding device and reduce the workload of manual detection,it is necessary to carry out on-line resistance testing technology.Therefore,this paper studies a grounding resistance on-line detection system,real-time monitoring of the grounding device operating conditions,to achieve the tank grounding online monitoring function,to obtain more accurate test results,improve detection efficiency.The research and development work of the grounding resistance on-line detection system was completed,and the prototype technology and prototype were formed,and the on-line resistance on-line detection system was installed and used.Through comparison tests,determine the error value of the grounding resistance on-line detection system and the 4105 grounding resistance tester.A kind of permanent auxiliary grounding electrode is obtained by comparing with the existing grounding resistance on-line monitoring instrument,which makes it form a loop with the monitored grounding system to ensure that it is not restricted by the diagonal length of the grounding system and the surface hardening treatment.The impulse grounding resistance of the high energy waveform lightning current passing through the grounding system in the simulated lightning current makes the measured resistance more realistic.The grounding device change monitoring technology and the grounding system grounding resistance on-line monitor can be used to monitor ground network operation status intuitively and quickly.The response speed is fast and saturation is not realized.Real-time detection can be realized,and the 10000m~2earth network resistance amplitude and waveform can be tested;Anti-stray current,electromagnetic interference function,and wireless transmission data performance,timely rectification of the problem of the ground network,so as to ensure the normal operation of the tank ground network.