On the evening of October 27, 2024, a new Chinese-made 500kV transformer was successfully delivered to the 500kV Shangdang Substation in Zhenjiang, Jiangsu Province. This marks a significant step in the capacity expansion and replacement project for the main transformer at this vital regional hub. Upon completion, the project will enhance grid infrastructure and better meet the electricity demands driven by regional economic growth.
Earlier this year, on August 3, the National Development and Reform Commission (NDRC) and the National Energy Administration (NEA) announced the “Large-Scale Equipment Upgrade Plan for Key Energy Fields,” which aims to modernize equipment and technology in power transmission and distribution to support the development of a new energy system. The 500kV Shangdang Substation is crucial for transmitting electricity across China, being the first 500kV substation in Zhenjiang. It currently has four main transformers, with the No. 1 transformer, operating at 750 MVA, having been in service for 29 years. Its age has led to severe deterioration, and many of its accessories are imported, making maintenance challenging due to long replacement times.
In response to the NDRC’s requirements and to improve the infrastructure of essential hub substations, the State Grid Zhenjiang Power Supply Company is executing this capacity expansion project using a “demolish old before installing new” approach, following a phased power outage plan. The old 750 MVA No. 1 transformer will be replaced with a new 1000 MVA Chinese-made unit. Currently, the dismantling of the No. 1 transformer, along with its switches, protections, and cables, has been completed, and the entire project is set to be fully operational by December this year.
