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ELECTRIC LOAD MANAGEMENT

SCADA, with its relatively expensive RTUs installed at distribution substations, can provide status and measurements for distribution feeders at the substation. Distribution automation equipment is now available to measure and control at locations dispersed along distribution circuits. This equipment can monitor sectionalizing devices (switches, interrupters, fuses), operate switches for circuit reconfiguration, control voltage, read customers’ meters, implement time-dependent pricing (on-peak, off-peak rates), and switch customer equipment to manage load. This equipment requires significantly increased functionality at distribution control centers.

Distribution control center functionality varies widely from company to company, and the following list is evolving rapidly.

• Data acquisition: Acquires data and gives the operator control over specific devices in the field, Includes data processing, quality checking, and storage.

• Feeder switch control: Provides remote control of feeder switches.

• Tagging and alarms: Provides features similar to SCADA.

• Diagrams and maps: Retrieves and displays distribution maps and drawings. Supports device selection from these displays. Overlays telemetered and operator-entered data on displays.

• Preparation of switching orders: Provides templates and information to facilitate preparation of instructions necessary to disconnect, isolate, reconnect, and reenergize equipment.

• Switching instructions: Guides operator through execution of previously prepared switching orders.

• Trouble analysis: Correlates data sources to assess scope of trouble reports and possible dispatch of work crews.

• Fault location: Analyzes available information to determine scope and location of fault.

• Service restoration: Determines the combination of remote control actions that will maximize restoration of service. Assists operator to dispatch work crews.

• Circuit continuity analysis: Analyzes circuit topology and device status to show electrically connected circuit segments (either energized or de-energized).

• Power factor and voltage control: Combines substation and feeder data with predetermined operating parameters to control distribution circuit power factor and voltage levels.

• Electrical circuit analysis: Performs circuit analysis, single-phase or three-phase, balanced or unbalanced.

• Load management: Controls customer loads directly through appliance switching (e.g., water heaters) and indirectly through voltage control.

• Meter reading: Reads customer’s meters for billing, peak demand studies, time of use tariffs. Provides remote connect/disconnect.

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