New generator split-phase transverse differential protection based on wavelet transform

This paper presents a new split-phase transverse differential protection for a large generator based on wavelet transform. Research results show that there is almost no harmonic component on normal conditions, but it will produce great high-frequency current component when an internal fault occurs, which can be used to detect generator internal fault. With decomposition and reconstruction of the transient currents with wavelet transform, the high-frequency band fault currents are exploited in the new scheme. And the realization of the proposed protection device is also described in this paper, including the relay software and hardware design. The results from the experimental and field tests demonstrate that the new scheme is successful in detecting the generator internal fault. It has higher sensitivity and selectivity than the traditional protection scheme