Research On The Digital Protection Of Coal Mine Anti-override Tripping System

The safe operation of power supply network in coal mine is an important precondition for normal production of coal mine,and relay protection system plays an essential role in protecting it.Influenced by various factors,when the power supply network is in actual operation underground the coal mine in China,it will often appear the switch tripping of the superior substation caused by the failures of the substation feeder at a lower level,and then expand the power supply interrupted districts underground,further affect safe operation as well as normal production of mine.Therefore,the study on causes of override trip and corresponding measures has great significance on improving production efficiency and reducing casualties.Components of power supply system in coal mine were analyzed,and causes of override trip underground the coal mine as well as traditional tripping protection methods were discussed in this paper.Further studies included fiber-optic current longitudinal differential protection,IEEE1588 clock synchronization technology theory,IEC61850 communication standard.Based on above research and analysis,three-tier network architecture combining process layer,spacer layer and control layer in accordance with IEC61850 communication standard was adopted,and protection system against override trip of power supply network in coal mine was designed.Thus,integration of network information sharing and control of electricity equipment were realized,and override trip problem of power supply in coal mine could be solved.Therefore,it created conditions for the coal mine substation unattended.After the test and debug,validity of the system is verified and the goal of safety power supply of coal mine were achieved.The study on digital system against override trip of power supply network in coal mine provides reliable protection for safety production underground the coal mine,and could effectively improve the efficiency of coal mine safety production and ensure the safety of the underground working personnel,baring great theoretical significance and engineering value.