This project belongs to the field of laser technology in electronics and communications science. The power grid is the core foundation supporting the rapid development of the city, and high-voltage power cables are the lifeblood of the entire power grid's efficient operation. Therefore, how to achieve early warning of urban high-voltage cable operation faults and online monitoring of its safety has always been an urgent problem in the power industry. Acoustic emission monitoring based on partial discharge is one of the important technical means to achieve power system safety monitoring. Optical fiber acoustic emission sensing technology is an emerging technology industry that supports high-voltage power safety because of its advantages of resistance to electromagnetic interference, intrinsic safety, remote online real-time measurement, high sensitivity, and low cost. The project is aimed at the needs of online monitoring of partial discharge safety parameters of high-voltage power cables. It has been funded by the National Natural Science Foundation of China, key projects of Shanghai City Science and Technology Commission, and science and technology projects of State Grid Shanghai City Power Company. The R & D team consists of ldquo; National Outstanding Youth Rdquo;, ldquo; Shanghai City May 1st Labor Medal Winner rdquo;, ldquo; Shanghai Leading Talent rdquo;, ldquo; Shanghai Young Oriental Scholar rdquo; etc. Carry out research and development from special sensing optical fibers, sensor design and preparation, photoelectric detection systems and software development and engineering applications, forming an optical fiber sensing technology system for high-voltage power cable safety monitoring with independent intellectual property rights, solving practical problems in online monitoring, and playing an important role in urban power grid safety monitoring. The main technical innovations of this project include: (1) Proposed a coaxial double-clad structure optical fiber technology for local sound emission vibration sensing, which solves the problem that the parameters of traditional optical fiber interferometers are not easy to control, and achieves high sensitivity to local sound emission vibration signals. and broadband monitoring. (2)A high-sensitivity partial discharge acoustic emission vibration sensing head technology is proposed. Based on a high Poisson ratio silicone rubber elastomer, the optical fiber sensing sensitivity is enhanced, thereby breaking through the core problem of direct sensing of weak partial discharge acoustic emission signals by optical fibers and realizing high-voltage cable partial discharge early warning. (3)An accurate phase extraction technology for a phase-sensitive optical time domain reflection sensing system is proposed, which breaks through the problem of identifying false alarm signals in system fading and realizes accurate testing of local sound emission signals. The project has obtained a total of 6 authorized patents, applied for 4 invention patents, and 1 software copyright. The research results have been highly recognized by domestic and foreign counterparts in the field of optical fiber sensing technology, and 20 papers have been published in high-level academic journals and conferences. The scientific and technological novelty search conclusion of the national scientific and technological novelty search agency pointed out: quot; The comprehensive technical level of the project has reached the international advanced level quot;. This achievement was developed by Shanghai University, State Grid Shanghai City Power Company and Shanghai Sanyuan Cable Accessories Co., Ltd. in industry-university-research cooperation. It has been used in more than ten high-voltage cables such as the World Expo Tunnel, Longyang Road Section Tunnel, and Xueye Road of State Grid Shanghai City Power Company. Applied on the line. The new output value was 218.4 million yuan; the new profit was 35.12 million yuan; the new tax revenue was 12.29 million yuan; and the savings were 56.23 million yuan; the system developed by the project was also applied in high-voltage cables such as Changshu and Zhangjiagang in Jiangsu Province, involving indirect economic benefits of 17.2 million yuan. The project has achieved major breakthroughs and innovations at the international advanced level, and has played a leading role in the fields of optical fiber partial discharge acoustic emission detection and high-voltage power cable safety monitoring, with significant social and economic benefits.