One of the ten largest electrical power producers in the United States implemented RealFlex as a key component in its first distribution automation project.
PROBLEM DESCRIPTION AND SYSTEM REQUIREMENTS:
The firm had been investigating centrally controlled Distribution Automation (DA) for a number of years. From previous pilot experiences, the client recognized the traditional “point to point” wiring between the equipment controller and the RTU was expensive, difficult to maintain and impossible to migrate into future technologies. In addition, they were looking for an inexpensive SCADA solution that would allow:
Remote monitoring and control
The ability to address multiple communications ports with different drivers/protocols
Handling a large number of points while maintaining realtime performance
They had to find the right combination of SCADA software, field equipment, system integration, communications and feeder design to install DA on twenty-three 13kV distribution feeders with the primary goal of reducing customer outage durations.
Utilizing a combination of RealFlex and FlexView, the system is monitored and controlled from locations around the state. Twelve 900 Mhz master radios operating on different licensed frequencies are installed throughout the service territory to provide coverage. Utilizing Cooper reclosers (which were chosen after evaluation of motor operated switches, load interrupters, reclosers and sectionalizers), faults are isolated and power re-routed, re storation is controlled by the RealFlex operator. With cooperation from Cooper and Motorola, the client was able to integrate the Cooper 4C/LS controller with the Motorola MOSCAD RTU utiizing protocol transmission software. This software, which resides on the MOSCAD RTU, polls the 4C/LS controller in PGE-2179 protocol, recognizes exceptions and translates them into Motorola’s MDLC protocol for transmission through the 900 Mhz system back to the RealFlex server. RealFlex accesses the data utilizing a MODBUS protocol scanner that was customized for the MOSCAD RTU interface. The system allows remote personnel to monitor over 9000 points. Control Sequence Language (CSL) is used to automatically test radio batteries and other field equipment. Hot Standby with Automatic Failover insures redundancy at the SCADA master station.
The client has an extremely inexpensive system that is maintained by operators. Field personnel are able to send controls and make adjustments to the system remotely. Customer outage duration rarely lasts longer than 5 minutes and is often avoided completely, thanks to the Distribution Automation System.
REALFLEX SYSTEMS SOFTWARE:
RealFlex, Hot Standby with Automatic Failover, MOSCAD I/O Driver
Motorola MOSCAD RTUs, Cooper Type VSA recloser, 900 Mhz radio communications