Automated Feeder and Recloser Control: Reducing Outages with Predictive Technology

Automated Feeder and Recloser Control - Automation of feeders and reclosers supports rapid fault isolation, improving grid uptime and reliability.

Automated Feeder and Recloser Control is the foundational technology for distribution network reliability. A recloser is essentially a smart, automated circuit breaker deployed along a feeder line. Its function is to automatically interrupt power when a fault occurs, and then test the line by re-closing after a set time. Since a high percentage of faults are temporary (e.g., a tree branch briefly touching a line), the recloser successfully restores power without a sustained outage.

The "automation" part involves coordinating multiple smart reclosers and sectionalizers in a scheme. When a permanent fault occurs, the system's logic isolates the fault between the nearest two devices, ensuring only the smallest possible line segment is de-energized, while power is re-routed around the fault to unaffected customers. This is the mechanism that delivers the self-healing capability.

FAQ on Automated Feeder and Recloser Control

Why do reclosers typically attempt to close the circuit multiple times after a fault? They attempt to close the circuit multiple times (often two to three) because the vast majority (upwards of 80%) of overhead line faults are transient or temporary (e.g., a bird or lightning strike). The temporary interruption allows the fault cause to dissipate. If the recloser successfully closes and the current remains normal, a prolonged outage is avoided.

What is the difference between a recloser and an automated sectionalizer in a DA scheme? A recloser is a protective device that can both sense and interrupt fault current. An automated sectionalizer is a switching device that can only open a circuit (it cannot interrupt the fault current) and is designed to open only after an upstream recloser has operated a pre-set number of times, thereby coordinating to isolate a permanent fault.

How does the automation of feeder control reduce the utility's operational costs? It significantly reduces operational costs by minimizing the need to dispatch maintenance crews for non-permanent (transient) faults. By automatically isolating permanent faults to the smallest area, it also helps crews quickly pinpoint the fault location, reducing fault-finding time, and ultimately speeding up the full service restoration.