February 24, 2003

IntelliTEAM^® Improves Reliability of Remote Substation.

Background

A large Western utility has a problem faced by many utilities with substations in remote areas. Their substation was served by preferred and alternate 25-kV sources, using manually operated load-break switches. The primary source runs through a rural river delta area dedicated almost exclusively to agriculture. In a typical year, customers served by this substation would experience several outages, attributable to large birds and accidents involving agricultural implements. Because of delays in outage reporting and the commute time for service crews, several hours might pass before a crew could troubleshoot a problem and transfer the load. The slow response in restoring service was causing customer complaints.

What did they do?

The utility decided to use the S&C IntelliTEAM® Automatic Restoration System to address the issue. They installed a two-member team: two Model 5801 Switch Controls with IntelliTEAM software, set to transfer load on loss of the primary source. They configured the controls to transfer immediately to the alternate source on the second loss of voltage (the second source-side recloser operation). A major benefit of the IntelliTEAM system is its ability to detect faults on the load side of the switches, which prevents the alternate source from closing into a fault.

The Model 5801 Switch Controls were paired with two 25-kV S&C Scada-Mate® Switches that replaced the old air-break switches. The Scada-Mate Switches were equipped with voltage and current sensors on all three phases.

Because the switches were located within the substation fence, approximately 100 feet apart, the utility chose Dymec Fiber-Optic Transceivers to provide peer-to-peer IntelliTEAM communication. They ordered one of the switch controls with PG&E gateway software and a 900-MHz radio, so the team could communicate back to their distribution operations center using PG&E protocol.

Results

Within the first 18 months, the IntelliTEAM operated four times, significantly reducing the outage time for customers and saving emergency trips to the field. Since IntelliTEAM automatically accounts for any fault on the load side before transferring, it is considerably faster than SCADA operation would be. The utility configured the IntelliTEAM to automatically return to the preferred source once the problem is fixed, so there’s no need for a second trip to the field.

Complaints have essentially been eliminated — customers see only a blink of their lights instead of an extended outage.