Fault Location, Isolation and Service Restoration

The need for fast and effective fault location, isolation and service restoration lies at the heart of distribution feeder automation.

Locating faults a multi-step and time-sensitive process. The general ability to sense feeder faults is normally available as awareness of the fault comes from a nearby switch or other piece of protection equipment—and also from the sudden rise of customer calls to the service center. However, determining the precise location of a fault usually involves the deployment of one or more lines-people to check the connecting circuits and equipment. Sometimes this may have to be done in very bad weather conditions.

Even so, requirements are being placed upon utilities by their regulators to improve upon their 'outage time to power restoration' results. Penalties are being applied for poor outage frequency numbers and excessive outage durations.

NATIS Solution
The Natis Secure Distribution Automation Platform (SDAP) provides utilities with the ability to locate and isolate faults with greater accuracy. The SDAP provides direct communications with the remote fault sensors that are placed on the circuits and reports those faults directly back to the monitoring SCADA application to identify the exact location of the fault. If the SDAP is also deployed for providing operation and control of the remote feeder switches, sections of the circuit can be opened and closed to re-establish power and isolate the fault.

In addition, if the Natis products are implemented with our Smartgroup^TM software, then it is possible for groups of devices on the feeders to communicate with each other locally and to take pre-determined, corrective action automatically. In other words, conduct auto-sectionalizing operations.

Using Natis products for fault location and sectionalizing can minimize the impact and duration of outages, both in terms of the numbers of customers affected and the time taken to locate faults.