Honggou Substation is a hub substation of the Sichuan-Chongqing power grid and also a key AC support point for the ±800 kV Fufeng, Jinsu, and Binjin Ultra-High Voltage Direct Current (UHVDC) projects. Through precise voltage transformation, the main transformers in the substation undertake the critical task of transmitting hydropower from the Ertan Hydropower Station to regions such as Chengdu and Chongqing. The 500 kV Hongban Line connected to this substation is one of the 8 interconnection lines between the Sichuan and Chongqing power grids; equipped with circuit breakers that can quickly cut off fault currents to ensure line safety, the line has a maximum transmission capacity of 3.2 million kW. As a key channel for transmitting electricity from Sichuan to eastern regions, it can deliver over 8 billion kWh of clean electricity to Chongqing's load center annually.
Since its commissioning, Honggou Substation has completed a number of major technological transformations to continuously optimize equipment performance. In 2006, it put into operation the first static var compensator (SVC) in the Sichuan power grid and upgraded the opening and closing control logic of supporting circuit breakers, further improving the system's voltage stability and fault response speed; in 2013, it completed the comprehensive automation transformation of the entire substation, realizing remote monitoring, status data collection, and automatic operation of key equipment such as disconnectors and circuit breakers, which laid a solid technological foundation for the "unattended" operation mode; in 2014, it finished the transformation of the Hongban Line, adding drop-out fuses at the line's branch nodes to enhance the on-site protection capability against line overloads and short-circuit faults while optimizing the parameters of conductor cross-sections to significantly improve the outward power transmission capacity; in 2019, it was connected to the Southwest AC-DC Coordinated Control System, and through the coordinated regulation of equipment such as main transformers and circuit breakers, it further supported the stable operation of the regional power grid; in 2022, it replaced the 500 kV high-voltage reactors on the Puhong I, II, and III Lines that had been in operation for 24 years, and simultaneously overhauled the supporting disconnectors and circuit breakers, comprehensively raising the intrinsic safety level of the equipment.
Over the years, the operation and maintenance (O&M) team of Honggou Substation has adhered to the "strict, meticulous, and pragmatic" work style, implemented dynamic assessment and full-process safety management, and continuously carried out technical training. The O&M personnel conduct special accident prevention drills for main transformers, circuit breakers, and disconnectors every month, conduct line-side safety analysis every week based on the operating temperature and action records of drop-out fuses, and implement daily pre-control measures for potential hazards such as equipment joints and insulating parts. Adhering to the principle that "Minor defects are addressed within a shift, and major defects are resolved within a day," the team ensures the safe and stable operation of all equipment in the substation.