China has officially launched its first self-developed large-scale variable speed pumped storage unit's AC excitation system, located at the 300MW variable speed pumped storage facility in Langjiang, Zhaoqing, Guangdong Province. This milestone signifies a groundbreaking advancement in the unit's core components, endowing it with enhanced stable regulation capabilities. Leveraging cutting-edge technology, the excitation system boasts a capacity tenfold that of conventional fixed-speed units, effectively breaking the monopoly held by foreign technologies. With the ongoing construction of pumped storage projects, domestic variable speed units are anticipated to commence operations and generate electricity from 2026 to 2027, thereby accelerating the development of a new-type power system in China.