Research And Application Of Differential Faulty Line Detection In Coal Mine

This paper analyzes the leakage model of underground power system and the logicalrelation of zero sequence current in each branch,expounds the fault feature algorithmbased on this logical relationship and differential theory, put forward a differentialleakage protection method.Discusses by meanings of double eigenvalue positioninglong-line leakage fault location method based on the value of differentialcharacteristics,made this mathod of differential protection has ability to line selectingand locating advantages.Discusses the possible existence of a series of limitations of this method,andoptimal designes based on the characteristic of leakage fault system which has artificialneutral point grounding by reactance coil to inductive compensation. Builds a mineelectric leakage fault system model in MATLAB,the simulation and experiments resultsshow that this mathod of differential protection has effective line selection andjudgment ability. Discusses the the performance limitations and and solutions ofdifferential protection device,it is proved that this method has a strong practical value.