The "Distributed Small Current Grounding Line Selection System" developed by Xiangyang Keneng Electromechanical Equipment Co., Ltd. according to the principle of "fuzzy theory" has applied for invention patents and utility model patents, and passed the ISO system certification, and the accuracy of line selection has reached over 98%. It not only solves the need of protection line selection for neutral point ungrounded system; It also solves the need of neutral point protection line selection through arc suppression coil or resistance grounding system; It can also meet the protection line selection when multiple lines are grounded at the same time when multiple buses are connected in parallel or in combination with segmented operation modes. When the transition resistance is high when grounding or the system has resonance, the line selection can be accurate. The device has been installed and used in more than 300 substations. From the feedback of users, the effect is very good, which meets the requirements of power system for reliability and has the world-leading level. It has completely solved the worldwide problem of single-phase grounding fault, which has epoch-making significance! It has made innovative contributions to power system automation!
The company has obtained dozens of qualification certificates! A variety of products won the electric power technology progress award; Bus-type zero-sequence current transformer passed the test of power equipment quality inspection and testing center in power industry; The research achievements of distributed single-phase grounding fault computer comprehensive line selection device have been supported by the Innovation Fund of the Ministry of Science and Technology of China, and have passed the testing and certification of various technical indexes of the State Grid Electric Power Research Institute.