China: China announces it has brought the world’s largest smart direct current (DC) transformer into operation, marking a major step for its power grid. Power lines and transformers remain essential to modern electricity systems, and this new unit highlights how important they still are, even in a high-tech age.
Revealed in late 2025, the transformer is rated at 750 million volt-amps, according to its maker, Changzhou Xidian Transformer. It works with DC power, which is better than alternating current (AC) for sending large amounts of electricity across long distances.
What makes the transformer “smart” is its use of real-time digital controls. These allow operators to adjust current, temperature and voltage as needed. The unit is part of a high-voltage direct current (HVDC) system and is designed to improve the stability and reliability of long-distance power transmission. It can also respond more effectively to changes in output from renewable energy sources.
The new transformer replaces earlier HVDC units rated at 587.1 MVA. Those older models once held the world record for capacity, but China’s latest system goes significantly further.
The upgrade follows problems in the northwest power grid, which suffered an unexpected failure in autumn 2024. The issue was linked to low-frequency power oscillations, where short-term changes in supply and demand caused instability. This was a serious risk in regions like Xinjiang, home to huge wind and solar farms, where power output depends heavily on weather conditions.
As China continues to expand renewable energy, making sure electricity can be safely and efficiently delivered across the grid has become a top priority.
Source: MSN
