Electric Energy T&D - Index

Electric Energy T&D - EE Magazine March / April 2009 - Index

Integrated SCADA/DMS/OMS: Increasing Distribution Operations Efficiency
figure 1 - Outage Management Systems Improve Reliability Through
Enhanced Outage Analysis, Fault Location, and Crew Management
3 I March-April 2009 Issue
Distribution Management Systems
In comparison to OMS, DMS functionality is relatively new. While
DMS applications are utilized in outage management processes, DMS
also extends to the efficient management of planned work and normal
electrical operations. DMS is also typically associated with receiving
real-time status and analog points from the distribution system,
and the generation of supervisory control commands to distribution
breakers, switches and reclosers, switched capacitor banks, voltage
regulators, and load tap changers (LTCs). The importance of DMS
will increase as additional amounts of customer generation, energy
storage, and demand response are placed on distribution systems.
DMS is receiving a lot of attention because it can provide solutions to
many challenges distribution organizations face today. Table 1 below
contains a listing of DMS applications, functionality and benefits.
Integration of OMS and DMS
Integrated DMS/OMS provides a number of benefits to the distribution
organization, as discussed below.
1. Integrated DMS/OMS Improves Operator Efficiency
An integrated DMS/OMS assists operators in performing their
responsibilities better, compared to separate DMS and OMS systems.
Displays have the same appearance and can provide a single intuitive
interface for navigation. Additional displays for separate systems are not
required in already-crowded operator workspaces. Operator training is
minimized, since operators only need to learn the features of one GUI.
DMS Application Functionality Benefits
Unbalanced Load flow
analysis
Load allocation & State
Estimation
Determination of the line currents and node voltages per phase
for the entire distribution system, either on-line or off-line in
simulation mode
Intelligent allocation of telemetered or historical measurements
over the network to calculate estimated power flows, voltages,
and limit violations based on real-time conditions
• Improved system awareness
• Higher asset utilization
• Improved contingency planning
• Improved load flow & state estimation
calculations
• Improved notification of overloaded
equipment and voltage violations
fault Location Identification of possible fault locations on system • Improved crew efficiencies in managing
outages
• Reduced CAIDI and SAIDI
restoration Switching
analysis
distribution volt/var
control
Evaluation of isolation and restoration switching schemes • Improved operator efficiencies during
outages
• Increased reliability
Monitoring and control of line capacitors, voltage regulators, and
LTC’s to reduce peak load and system losses
Line Unloading Computation and analysis of load transfer options, including
overload reduction
remote Switching &
restoration
Automatic feeder reconfiguration considering network operating
conditions
Table 1 - DMS – Improving the Management of Distribution Systems
• Reduced customer demand at system
peaks
• Lower system losses
• Improved voltage profiles
• Reduced thermal-mode failures
• Longer equipment life due to reduced
overloads
• Higher asset utilization
• Reduced CAIDI and SAIDI
• Lower system losses