The Research Of Hydeo-generator Rotor Winding Inter-turn Shoft Circuit Fault

Hydro-generating unit is the key power equipment in the hydropower plant. The reliable operation of hydro generator is directly related to the hydropower plant to provide electricity reliably. The hydro-generator inter-turn short-circuit of rotor windings is a common fault, so it’s necessary to research the hydrogenerator rotor winding inter-turn short circuit fault.This paper analyses the reason of fault, the fault features, and the electromagnetic properties after rotor winding inter-turn short circuit, get the fault characteristic that is stator phase windings internal appear the fractional harmonic circulation, and the amplitude grows with the severity degree of short circuit. Based on multi-loop theory build the multi-loop mathematical model of hydro generators with inter-turn short circuits fault of field windings, the value of the circular current in stator winding parallel branches of same phase for different short circuit turns of rotor winding are calculated quantitatively. The simulation results are consistent with the theoretical analysis, the validity of the model is verified. So the fault electric parameters can be calculated quantitatively by the model, the protection basis for the inter-turn short-circuit of rotor windings has been provided.