A Fault Location Method of Stator Winding Inter-turn Short Circuit for Synchronous Condenser Based on Phase Angle Difference

In order to enhance the maintenance efficiency, a fault location method based on the phase angle difference is proposed to cope with the inter-turn short circuit fault in the stator winding of synchronous condensers. First, the phase angle of three-phase current, the magnitude and the phase angle of the fundamental zero-sequence voltage are obtained. If the fundamental zero-sequence voltage magnitude exceeds the threshold value, the inter-turn short circuit fault in the stator winding is detected. To locate the faulty phase, the phase of the fundamental component of zero-sequence voltage is compared with each phase of the three-phase current, respectively; thus, three groups of phase differences can be obtained. Then the turn-to-turn short-circuit fault occurs in the stator winding of the phase to which the minimum of the three groups of phase differences belongs, so as to realize fault location. To validate the effectiveness of the proposed fault location method, the simulation model is established by using a TTS-300-2 synchronous condenser, while a small synchronous machine develops the experimental platform to obtain the simulation and experimental results. The experimental results show that the amplitude of the zero sequence voltage fundamental wave can be used to diagnose whether the synchronous condenser has an inter turn short circuit fault, and the phase difference between the zero sequence voltage fundamental wave and the stator current fundamental wave of each phase can be used to achieve the fault location. ©2023 Chin.Soc.for Elec.Eng.