Digital dispatching brings order to Nanjing's low-voltage grid

Staff members from State Grid Nanjing operate the low-voltage mobile terminal. [Photo provided to chinadaily.com.cn]

A low-voltage busbar fault on a pole‑mounted transformer required urgent repair on July 24. Frontline staff uploaded the outage plan via a mobile terminal, and the dispatcher quickly approved it, cutting customer outage time by two‑thirds compared with conventional procedures.

This routine operation reflects the new low‑voltage dispatch management system established by State Grid Nanjing Power Supply Company.

Low‑voltage networks are the part of the grid most visible to customers. Nanjing has over 60,000 such service areas — 15 times the number of medium‑voltage zones. Frequent equipment changes and outdated data previously made it hard to manage massive work plans, limiting reliability improvements.

In 2025, State Grid Nanjing was named a national low‑voltage reliability pilot by the National Energy Administration. Starting in January, it systematically built a low‑voltage dispatch system, shifting from decentralized response to unified control.

During development, it issued citywide dispatch notices and detailed command rules. In March, it launched a dispatch management platform that aggregates maintenance information and visualizes the entire low‑voltage network from substation to customer.

Using metering devices, the platform cleans large volumes of operational data, giving real‑time visibility across the city.

In May, mobile terminals were deployed, enabling field teams to report plans and progress in real time, ensuring full interaction with dispatchers and repair crews and standardizing workflows.

To date, the system has managed 450,000 low‑voltage work orders and preemptively handled over 300 fault defects.

As a result, frequent‑outage service areas fell 34.4 percent year‑on‑year, unexplained outage customer‑hours dropped 11.8 percent from the start of the year, and average outage duration per customer decreased 48.8 percent year‑on‑year. The low‑voltage network now operates more efficiently, with a clear and transparent record that provides a full, traceable picture.