On the 24th, a new generation of relay protection system (Huaneng Ruiwo relay protection system) independently developed by Chinese enterprises was officially put into operation at Xiaowan Hydropower Station in the middle and lower reaches of the Lancang River. This means that the core control system known as the "brain" of hydropower stations has been fully localized, which is also a major technical breakthrough in China's hydropower control system. The computer monitoring, governor, excitation and relay protection systems are the core control systems of hydropower stations and the important basis for ensuring the stability of units and power grids. Among them, the computer monitoring system is equivalent to the "nerve center" of the hydropower station, the governor and excitation system are the actuators to ensure the voltage and frequency stability, and the relay protection equipment is the "first line of defense" to ensure the safe and stable operation of the power system. Previously, the key components of the hydropower core control system were imported. China Huaneng Group took the lead in setting up a joint R&D team to carry out a large amount of adaptation, comparison and R&D work on the software and hardware of the hydropower core control system, realizing 100% national production of software and hardware. The team completed 34 major technological innovations, and 17 key technologies filled the domestic gap. The Huaneng Ruiwo Hydropower Relay Protection System put into operation this time marks that the core control system in the field of high water head and large capacity hydropower generation in China is fully autonomous and controllable, further improving the operation level and intrinsic safety of China's power infrastructure. It is verified by the third-party authority that the performance indicators meet the requirements of the industry standards, which is of great significance to ensure the security of the power infrastructure network and the national energy security. (Liu Xinshe)