Research and Application on the Method of Rotor Winding Sweep Frequency Impedance Measurement

To increase the sensitivity of detecting the rotor winding inter-turn short circuit fault, we developed a new rotor winding deformation detection system based on sweep frequency impedance(SFI) method, a double water internal cooling condenser and a fault simulator generator was tested separately by the system, and a 660MW generator rotor was detected and analyzed by artificial short circuit fault. The results show that the SFI detection system has a high repeatability, the rotor winding inter-turn short circuit fault will change the data of low frequency including the value of SFI curve at 50 Hz, it will significantly change the value of maximum resonance peak, and its degree of change is significantly higher than the other resonance peaks.