Loren Smith, Electric Utility Director
Stillwater Electric Utility (SEU) staff has designed and are deploying DA technologies into the SEU electric distribution system.
DA is a family of technologies including sensors, processors, communication networks, and switches that can perform a number of distribution system functions depending on how they are implemented.
In particular staff is working to deploy self-healing systems that are designed to perform automatic switching, reactive power compensation coordination, and other feeder operations/control.
There are three key components of DA and a self-healing system are: Reclosers, Controllers, and Electrical substation relaying equipment.
Reclosers: Reclosers are installed to protect the distribution system by interrupting electrical currents during fault conditions. They are pole mounted three phase switches designed to quickly open or close dependent upon how they are programmed in the system
Controllers: Modern distribution system reclosers/switching devices use computer controls that are mounted at the ground level with user controls. The controllers act as the “brains” of the recloser/switching device. Through the use of sensors, processors, and communication networks they operate based on how they are programmed in the DA network, and what they are sensing.
Electrical substation relaying equipment: SEU operates nine electric substations. Protective relays are a critical component of electric substations. They continuously monitor the power system, to react to abnormal conditions and cause circuit breakers, and other protective devices, to operate and safely control the flow of power.
In a self-healing system, when there is an outage in a particular area the DA technologies communicate quickly to isolate the problem and restore power to the majority of the customers, while manual restoration is performed on the isolated area.
With the implementation of DA, staff expects to improve reliability, service quality, and operational efficiency.
Aug. 10, 2017: The first set of DA technologies has been installed and is being tested to allow for automated switching to provide a backup power source to the water treatment plant and the airport––which also includes many residential customers.
Once installation is complete, crews will begin installing DA technologies in the area of downtown, which will provide multiple backup sources to ensure the area is restored quickly should there be an outage.
Sept. 17, 2018: Crews are working with contractors to improve network connectivity. Crews are also deploying controllers in the northeast part of town to improve power quality and reliability.