In order to early detect and locate circuit damage corona discharge, in accordance with its ultraviolet imaging features, the use of FPGA core processing platform is designed to ultraviolet and visible two-way signal acquisition, registration and fusion the real- time detection system. By optimizing the design of the hardware structure and fast image registration algorithm based on MicroBlaze soft- core control module, a method is proposed to achieve fast FPGA- based image registration, the realization of different focal lengths UV/visible real-time processing of video data fusion. The results show that this method can effectively improve processing speed and image fusion system efficiency, meets the UV signal detection and localization requirements. This method has been used in China Southern Power Grid line inspection.