Feeder automation is the core component of distribution network automation, referring to the use of technical means to implement intelligent monitoring and management of the feeder lines from the substation outgoing lines to the user equipment. It covers functions such as operation monitoring, fault location and isolation, and power restoration, aiming to enhance the reliability of the power grid.
This system is based on feeder terminal equipment (FTU) to achieve distributed and centralized collaborative control. It conducts remote switch operations by real-time collection of parameters such as voltage and current. In the event of a fault, it uses the longitudinal differential protection principle to quickly cut off the faulty section and relies on ring network reconfiguration to restore power supply to the non-fault areas. The communication network adopts a multi-level architecture of optical fibers and RS485 to support interaction between the main station and the terminal. Typical cases show that it can reduce the fault handling time from several hours by humans to seconds [1], and in the fully automatic mode, it can achieve power restoration within 1 minute [2]. In 2024, Fuzhou established an automatic FA operation and maintenance team, using AI technology to analyze the defect types of distribution automation terminals and successfully achieved automatic isolation of 250 grid short-circuit faults, quickly restoring 1047 transformers [3]. In 2024, Xiamen was the first to achieve 100% coverage of feeder automation in A+ power supply areas, and plans to complete 1098 feeder automation constructions in 2025 to achieve full coverage [4].
This technology has developed along with the ring network power supply structure. Initially, it achieved hardware upgrade by deploying remote controllable ring network switches and FTUs. Later, it combined communication technology innovations to form a mixed mode of closed-loop dominance and open-loop compatibility. Specialized equipment such as the DF9311 series products in the cable network has promoted the practical application of the technology. In 2025, the Shanxi power grid upgraded adaptive intelligent feeder automation devices, with the equipment response time shortened from 10 minutes to 2 seconds, and through protection coordination between sectional breakers, local rapid fault isolation was achieved [5]. Zhengzhou adopted the “graded protection + centralized feeder automation” self-healing mode, reducing the fault handling time to seconds [6].