1. Distribution Automation: Fault Detection, Isolation, and Restoration
Jeremy Blair, P.E. 8/31/2012

2. The Evolution of Sectionalization
Install Fuses to reduce Exposure to Trunk
Radial Recloser reduces Trunk Line Mile Exposure and Customer Count risk. ~25% reduction in Breaker CI.
Feeder Breaker R
New Radial Breakers reduce Trunk Line Mile Exposure and Customer Count risk
Feeder Breaker R
Tie Recloser can reduce breaker CI by another 25%!

3. FDIR Basics FDIR = Fault Detection Isolation Restoration
Automatically:
Isolates faulted line sections
Switches to restore power to unfaulted sections
Makes decisions using
Overcurrent/reclosing
Loss of Voltage (any phase typical)
Loading prior to outage (typically)
Preset capacity limits (typically)
What the other switches see (typically)
Does not typically LOCATE fault.

4. Variations & Considerations for FDIR Systems
Switching Equipment & Coordination (Motor Operated Switchgear, Reclosers, etc.)

5. Equipment Assessment for Cost Effective FDIR systems
Environmental
Regular Maintenance
Mechanical Speed
Interrupt Requirements
Motor Operated Switches
Corrosion, Ice loading
-Motor Operator
-Mechanism
-Blades
Seconds
Load Break
Enclosed / Padmounted Switchgear
Enclosed Mechanism
Electronic Sectionalizer
-Batteries
Cycles
Electronic
Recloser
Fault Break

6. Variations & Considerations for FDIR Systems
Switching Equipment & Coordination (Motor Operated Switchgear, Reclosers, etc.)
Logic Architecture (Centralized, Distributed)

7. Logic Architecture for FDIR systems
Distributed logic provides:
SCADA independence
Ability for targeted deployments of switching and telecom equipment
Avoid single points of failure without redundancy
Centralized logic provides:
One time large investment with low cost scalability
Possibility for FDIR as a SCADA/OMS add-on
Possibility for centralized support/programming
Ease of system visibility within logic (capacity, multiple sources, multiple contingencies)
Hybrid systems
Centralized logic on localized controllers like RTU’s or compact hardened computers.
Can be distributed to whatever level necessary…regional SCADA host, substation, switch controller

8. Variations & Considerations for FDIR Systems
Switching Equipment & Coordination (Motor Operated Switchgear, Reclosers, etc.)
Logic Architecture (Centralized, Distributed)
Communication
Centralized, Peer-Peer, None
IP, serial
Public, Private
Licensed Wireless, Unlicensed Wireless, Fiber, Copper

9. Variations & Considerations for FDIR Systems
Switching Equipment & Coordination (Motor Operated Switchgear, Reclosers, etc.)
Logic Architecture (Centralized, Distributed)
Communication
Centralized, Peer-Peer, None
IP, serial
Public, Private
Licensed Wireless, Unlicensed Wireless, Fiber, Copper
Deployment (Targeted, Risk-based, Systemwide)
Utility Footprint
Known Exposure zones
Regulatory cooperation
Operating rules (safety, capacity risk, switching procedures, etc.)

10. Value of Radial Sectionalization vs
Value of Radial Sectionalization vs. FDIR assuming even customer & fault distribution
Cust/2
Cust/2
Feeder Breaker R
Miles/2
Miles/2
Sectionalization Risk Reduction= 1-{[(Cust/2)(Miles/2) + (Cust/2)(Miles)]/(Cust*Miles)}
-for the cost of 1 Recloser per feeder: 25% CIAV
1-way Transfer Risk Reduction= 1-{[(Cust/2)(Miles/2) + (Cust/2)(Miles/2)]/(Cust*Miles)}
-for the cost of 2 Reclosers per feeder: 50% CIAV R
2-way Transfer Risk Reduction= 1-{[(Cust/2)(Miles/2) + (Cust/2)(Miles/2)]/(Cust*Miles)}
-for the cost of 1.5 Reclosers per feeder: 50% CIAV
Cust/2
Cust/2
Feeder Breaker R
Miles/2
Miles/2

11. Maximizing FDIR Effectiveness
Targeted deployments based on historical feeder performance can be deployed anywhere
Urban
Rural
High CIAV opportunity
High CMAV opportunity
Capacity Limits with full visibility allow for use of multiple sources
Capacity limits allow for load or voltage constrained installations
Scalability
Distance & vegetation may require point to point, low throughput comm’s
Can use meshing or short range comm’s

12. Maximizing FDIR Value Optimal Configuration
3 breaker, 2-way default = 50% CI reduction on two feeders
Case by case:
Goal is lowest $/CIAV and highest Customer Inclusion
More than two sources not beneficial (high $/CIAV) unless needed for capacity/visibility
Value of automation on second feeder
Customer & Exposure Distribution
Use of existing equipment provides low $/CIAV opportunities
Use of capacity limits allow beneficial installation of FDIR systems in more scenarios.

13. Capacity considerations for FDIR systems
90% of hours
at or below
70% of peak
-Equipment/System Intelligence:
-Entergy’s rule
-Visibility to support Capacity Limitations
-Prevent or limit scope of transfer

14. FDIR Program Value: Real Entergy Numbers
117 Automated Load Transfer (ALT) systems in service at 2011YE
265 individual switches installed
$13.25M in installed equipment
108,000 CI & 13,000,000 CM saved in 2011
~$123/CIAV annually for one year program value
~$31/CIAV annually for four years program value
Little maintenance required using magnetically actuated vacuum bottle switches & reclosers, so value grows with time!

15. Questions? Jeremy Blair, PE Entergy Jackson, Mississippi