Baoji Converter station repairs underway

The ±500 kilovolt Baoji Converter Station's comprehensive renovation and annual maintenance project has recently entered the power-off construction phase, marking Shaanxi province's first DC converter station control and protection retrofit.

Running from Sept 20 to Nov 18, the 60-day project adopts a synchronized "annual maintenance plus system renovation" model to address aging equipment hazards and comprehensively enhance the safe and stable operation of the Northwest DC transmission channel.

The construction covers core areas such as the converter station's DC yard, converter transformers, alternating current filter yard, and the first three lines, with key tasks including the renovation and upgrade of the DC control and protection system and the annual overhaul of AC/DC primary and secondary equipment.

On-site resources include over 260 maintenance and commissioning personnel, 28 special operation vehicles, and more than 1,000 sets of various testing instruments and tools. The project scope encompasses the renovation of 233 panels, the installation of 126 new panel cabinets, and the laying of nearly 200,000 meters of power and optical cables. This undertaking is characterized by its extensive scope, high technical difficulty, and complex cross-operation coordination, with no prior reference experience from similar projects within the province.

To ensure construction safety and quality, the site has implemented zoned operations and dedicated responsibility management, refining safety, technical, and quality accountability for each work area. Strict adherence is maintained to standardized work ticketing and operational protocols and secondary safety protection measures. Comprehensive isolation and item-by-item verification are conducted for neighboring live equipment, operational panels, terminals, and optical fiber interfaces, while critical processes are subject to full-time witness supervision to prevent various operational risks.

Throughout the site, requirements for civilized construction are enforced to ensure that work areas are cleared of materials and debris upon completion.

The renovation is being overseen by Shaanxi Power Transmission and Transformation Engineering Company, which is responsible for the entire process of construction and commissioning. Technical personnel were involved in preparatory stages such as drawing reviews and technical briefings, planning phase-based acceptance inspections in advance. Every process strictly implements self-inspection and mutual inspection to achieve synchronous closed-loop progress of construction and acceptance, ensuring zero defects in renovation quality.

It is reported that the control and protection system of the converter station has been in operation for over 15 years, with prominent issues such as equipment aging and frequent component failures. This comprehensive renovation will eradicate long-term operational hazards, improve equipment health and grid stability control capabilities, provide a safeguard for the long-term safe operation of the Deyang-Baoji DC transmission line, and accumulate valuable construction and technical experience for subsequent converter station control and protection renovations in Shaanxi.