State Grid Shangqiu Power Supply Company: Maintenance Without Power Interruption, Users Experience "Zero Awareness"

On March 26, the 110 kV Gangwang Substation in Zhecheng County underwent a comprehensive equipment maintenance. At the 10 kV Gangding Line grid-connected power generation site, a bustling scene unfolded as State Grid Shangqiu Power Supply Company deployed three medium-voltage power generation vehicles to ensure uninterrupted power supply during the substation overhaul. This marked the company’s first application of a combined “live-line operations + medium-voltage generators” mode in Zhecheng County, achieving a seamless transition for users and providing reliable power support during the substation’s spring maintenance.

The 110 kV Gangwang Substation’s spring maintenance involved critical equipment such as transformers and circuit breakers, requiring a full shutdown. However, the 10 kV Gangding Line, serving a wide area with concentrated user loads, could not transfer its load through conventional switching operations. A traditional outage would have left local businesses and residents without power for nearly 10 hours. After multiple on-site assessments and technical reviews, State Grid Zhecheng County Power Supply Company adopted the integrated strategy of “live-line operations + medium-voltage generators.”

At 5 a.m., three medium-voltage generators and insulated bucket trucks arrived on site. Teams specializing in safety control, load monitoring, and equipment operations collaborated to complete tasks such as device calibration, insulation checks, and phase verification. Using live-line techniques, they connected the generators’ three cables to the grid.

“All systems ready—initiating operation…” The orange generators hummed steadily, achieving seamless synchronization between the grid and backup power. By precisely aligning voltage, frequency, and phase angles, the transition occurred without user disruption, ensuring “zero awareness” of the outage.

Moving forward, State Grid Shangqiu Power Supply Company will expand the use of “live-line + generator” hybrid models, leveraging smart technologies to minimize outages and enhance grid reliability.(By Zhou Zhikun)