The 500kV-3x300MVA transformer is a product of a national-level science and technology project assigned to EEMC by the Ministry of Science and Technology. After being rated as excellent by the State Acceptance Council and receiving approval from Vietnam Electricity (EVN) for operation, EEMC proceeded with the transportation and installation at the AT2 position of the Hoa Binh 500kV Substation. Under the direction of EVNNPT and with the coordination of relevant units, the transformer was completely installed, tested, and calibrated on December 8, 2025.

AT2 transformer at  Hoa Binh 500kV Substation before the moment of energizing.

The Hoa Binh 500kV Substation Capacity Upgrade Project is a special-grade energy project, Group B, with an investment scale of replacing two existing 500/220/35kV-450MVA transformers with two 500/220/35kV-900MVA transformers, increasing the total substation capacity from 900MVA to 1,800MVA. Phase 1 involves replacing the AT2 transformer from 450MVA to 900MVA; Phase 2 involves replacing the AT1 transformer from 450MVA to 900MVA, which is expected to be completed in the coming period.

Relevant units witnessed successful energizing moment of AT2 transformer.

In the context where the 450MVA transformers at the Hoa Binh 500kV Substation frequently operate under overload conditions, upgrading the substation's capacity will contribute to ensuring operational safety as well as enhancing the power transmission capacity from large and small hydropower sources in the Northwest region. This ensures a stable power supply for Phu Tho province, the capital Hanoi, and other Northern provinces, especially in the context of high load demand. This is an urgent project that plays a vital role in ensuring national energy security.

For Dong Anh Electrical Equipment Corporation, this is a significant step forward, marking the first time a domestic enterprise has mastered the design and successfully manufactured a 500kV transformer with the largest capacity on Vietnam's transmission grid. Simultaneously, it helps EEMC train a team of design engineers, technology engineers, managers, and skilled technical workers to master the technological equipment line for 500kV transformer manufacturing. This success also serves as a premise for EEMC to continue striving for research and development of new products, contributing to the localization of key electrical equipment on Vietnam's power grid.

Translator: Vân Ly