© ABB Group
April 15, 2020 | Slide 1

Self healing grid strategies
Cleber Angelo
Outdoor Medium Voltage
Global Product Manager
© ABB Group
April 15, 2020 | Slide 2

Self healing grid strategies
 Challenges facing utilities today
 Situational analysis
 Improvement goals for self healing strategies
 Introduction to self-healing grid business models
 device level and /or peer to peer
 substation level
 centralized
 Detailed explanations of each business model including
 The type of investment required
 Expected reliability improvements
 Options to determine the best implementation strategy for your budget
 Summary
© ABB Group
April 15, 2020 | Slide 3

Self healing grid strategies
 The industry is moving toward a deregulated, competitive environment requiring accurate information about system performance to ensure maintenance money are spent wisely and customer expectations are met
 CAIDI and SAIDI scores are under close scrutiny from government agencies


System reliability pertains to both sustained interruptions and momentary interruptions
Any interruption of greater than five minutes is generally considered a reliability issue in some countries.
 Limited capital budgets for continued improvements in grid reliability
© ABB Group
April 15, 2020 | Slide 4

Self healing grid strategies
 Momentary interruption – A single operation of an interrupting device that results in zero voltage.
 Momentary interruption event - An interruption of duration limited to the period required to restore service by an interrupting device. This must be completed within 5 minutes or any other period determined by regulation agencies.
 Sustained interruption – any interruption not classified as a momentary interruption
© ABB Group
April 15, 2020 | Slide 5

Self healing grid strategies
 Implementing self healing or fault detection isolation and restoration
(FDIR) can help utilities:
 Improve CAIDI and SAIDI metrics by up to 33%
 Decrease restoration time to less than 30 seconds
 Reduce the cost of restoration
 Prevent lost revenues

Boost the utility’s reputation with customers, stockholders and government regulators
© ABB Group
April 15, 2020 | Slide 6

Self healing grid strategies
st
 Device level and/or peer-to-peer
 A group of reclosers, load break switches, and feeder circuit breakers operate together to restore power in the most optimal manner
 Benefits
 Allows utilities to focus investments on feeders that experience the most outages
 Fast implementation
 Initial low capital investment
 Target solution appropriate for problem feeders
 Improves SAIDI and CAIDI scores
© ABB Group
April 15, 2020 | Slide 7

Self healing grid strategies
Requirements for device level (no communications required)
 System topology representation

Feeders with single restoration path, generally open “tie switch”
 Pre-fault system status
 Normal voltage measurements at each node and on both sides of “tie switch”
 Pre-fault system loading (capacity check for the restoration done by protection or planning engineers)
 Fault detection and isolation
 Coordinated protection devices using standard protection curves and predetermined reclosing intervals
 Load restoration

Loss of voltage detected on one side of “tie switch” and on source side of reclosers on faulted circuit
 Timing sequence initiated
 If loss of voltage is sustained for predetermined interval, other reclosers open if necessary to continue isolation and “tie switch” closes restoring power

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
1 VT
Sectionalizing
Recloser
52
GridShield
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
Sectionalizing
Recloser
52
GridShield
Fault
X
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT 1 VT

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
Sectionalizing
Recloser
52
GridShield
Fault
X
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT 1 VT

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
Sectionalizing
Recloser
52
GridShield
Fault
X
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT 1 VT

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
Sectionalizing
Recloser
52
GridShield
Fault
X
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT 1 VT

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
1 VT
Sectionalizing
Recloser
52
GridShield
Fault
X
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
3
VT’s
1 VT
Midpoint
Recloser
52
GridShield
Tie Point
Recloser
52
GridShield
3
VT’s
1 VT 1 VT

Self healing grid strategies
Requirements for peer-to-peer (requires communications)
 System topology representation

Feeders with single restoration path, generally open “tie switch”
 Pre-fault system status
 Switch status (upstream and downstream information for devices)
 Pre-fault system loading (capacity check for the restoration)
 Fault detection
 Based on recloser lockout status and reclosing counter value change, or substation breaker trip signal
 Downstream node of the lockout switch is the fault location
 Fault isolation
 Downstream switch(es) of the fault location
 Load restoration
 Start from the downstream node of the isolation switches

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
Sectionalizing
Recloser
52
GridShield
Midpoint
Recloser
52
GridShield
IEC 61850 Communications
Sectionalizing
Recloser
Midpoint
Recloser
52
GridShield
52
GridShield
Tie Point
Recloser
52
GridShield

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
Sectionalizing
Recloser
52
GridShield
Fault
X
Midpoint
Recloser
52
GridShield
IEC 61850 Communications
Sectionalizing
Recloser
Midpoint
Recloser
52
GridShield
52
GridShield
Tie Point
Recloser
52
GridShield

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
Sectionalizing
Recloser
52
GridShield
Fault
X
Midpoint
Recloser
52
GridShield
IEC 61850 Communications
Sectionalizing
Recloser
Midpoint
Recloser
52
GridShield
52
GridShield
Tie Point
Recloser
52
GridShield

Device level
Substation
Circuit
Breaker
Source 1
Substation
Circuit
Breaker
Source 2
Sectionalizing
Recloser
52
GridShield
Fault
X
Midpoint
Recloser
52
GridShield
IEC 61850 Communications
Sectionalizing
Recloser
Midpoint
Recloser
52
GridShield
52
GridShield
Tie Point
Recloser
52
GridShield

Summary device level
 Initial low capital investment
 Target solution appropriate for problem feeders
 Best fit for single restoration path circuits
 Improves SAIDI and CAIDI scores
 Loop schemes requires voltage sensors
 Peer-to-peer requires high speed communications –
IEC61850 is only standards based peer-to-peer solution available with open protocol environment
 Protection/coordination engineers manage logic
© ABB Group
April 15, 2020 | Slide 20

Self healing grid strategies
 Substation level
 Coordinated control between groups of reclosers, load break switches, and substation circuit breakers within a substation and possibly with adjacent substations
 Benefits
 Avoids overloading of adjacent substations
 Reduces engineering support and recurring costs
 Target solution appropriate for problem feeders
 Supports future communications investments for applications such as asset health and volt/Var control
 Utilities realize benefits on groups of substations and the feeders they control
 Increases improvement in SAIDI and CAIDI scores
© ABB Group
April 15, 2020 | Slide 21

Self healing grid strategies
 IEDs monitor and control switches
 Substation computer collects data from IEDs
 FDIR active logic resides on substation computer
 Automatic identification and isolation of a fault
 Automatic power restoration
 Generally faster response than control centerbased FDIR
© ABB Group
April 15, 2020 | Slide 22

Substation level
Substation
Circuit
Breaker
Source 1
Sectionalizing
Recloser
52
GridShield
Fault
X
Midpoint
Recloser
52
GridShield
Substation
Circuit
Breaker
Source 2
DNP/IEC Communications
Sectionalizing
Recloser
Midpoint
Recloser
52
GridShield
52
GridShield
Tie Point
Recloser
52
GridShield

Substation level

Substation level

Substation level
Start
Obtain IED Information
Poll IED information
-Sw status (open, close, lockout)
-Sw recloser counter value
Sw Current …
No
Permanent Fault
Occurs ?
Yes
Generate Isolation Logic
Implement isolation control
Generate Restoration Logic
Implement restoration control
- Identify fault location
- Identify isolation switches
- Send isolation control command
- Confirm isolation actions
- Search alternative sources
- Obtain restoration solution
- Send restoration control
command
- Confirm restoration actions
© ABB Group
April 15, 2020 | Slide 26

Substation level
 Dynamic system configuration update
 Represent system topology through system single line
 Automatically generates logic for isolation and restoration via single line model
 System incidence matrix is dynamically generated based on
 System connectivity model
 Real-time system switch status
 Depth-first search strategy (traces all paths available to determine the optimal solution to restore power)
 Fault restoration
 Load current-based capacity check (pre-fault load current)
 Single or multi-path restoration supported
 Multi-path restoration
– unserved loads picked up by multiple feeders
© ABB Group
April 15, 2020 | Slide 27

Summary Substation Level
 Initial low capital investment
 Target solution appropriate for problem feeders
 Can provide multiple paths for restoration, but generally best fit if all sources for restoration are from same substation
 Improves SAIDI and CAIDI scores
 Requires communications (lower baud, i.e., 9600) but possibly already in place
 Protection/coordination engineers must work with SCADA engineers.
 Should reduce customized logic in protection devices
 Utilities realize benefits on groups of substations and the feeders they control
© ABB Group
April 15, 2020 | Slide 28

Self healing grid strategies
rd
 Centralized
 Coordinated control between groups of reclosers, load break switches, and high voltage circuit breakers across the distribution grid
 Benefits
 Takes advantage of load profile forecasting
 Allows utilities to take a proactive approach to power management
 Highest level of worker safety
 Supports smart grid initiatives
 Utilities realize benefits across the grid
 Maximum improvement in SAIDI and CAIDI scores
© ABB Group
April 15, 2020 | Slide 29

Self healing grid strategies
 IEDs monitor and control switches
 Substation computer collects IED data
 Substation computer acts as gateway – serves IED data to control center
SCADA and DMS
 Restoration Switching Analysis (RSA) run on DMS
 Load flow analysis as part of RSA, i.e., full network model used
 Automated or advisory FDIR
 Generally slower response than substation-based FDIR, but more comprehensive solution
© ABB Group
April 15, 2020 | Slide 30

Centralized control
Source 2
52
52
( GridShield
52
Source 1
52 52
GridShield
Fault
X 52
GridShield
52
GridShield
52
GridShield
52
GridShield
52
GridShield
52
GridShield
Source 4
52
52
GridShield
52
GridShield
52
GridShield
Source 3
52
Source 4
52
B
52
GridShield
52
GridShield

Centralized control

Centralized control

Centralized control

Centralized control

Summary centralized control level
© ABB Group
April 15, 2020 | Slide 36
 Requires SCADA applications, generally DMS with load flow and short circuit capability
 Target solution appropriate for all feeders
 Can provide multiple paths for restoration from multiple substations
 Improves SAIDI and CAIDI scores
 Requires communications (lower baud, i.e., 9600) but possibly already in place.
 Protection/coordination engineers must work with SCADA engineers
 Should reduce customized logic in protection devices
 Utilities realize benefits on groups of substations and the feeders they control

Summary
 Electric System performance and reliability are continually being scrutinized by customers and regulators
 Performance indices are becoming more difficult to meet
 Bottom line is that utilities need flexible and adaptable solutions to reduce outage restoration times

No single solution meets every customer’s needs

Device level solutions are generally “low cost”, easy to pilot and can be implemented by protection and control group
 Substation level solutions provide multi-feeder restoration paths, again are easy to pilot and can re-use existing equipment and communications infrastructure
 Centralized solutions offers most flexible and comprehensive restoration options.
© ABB Group
April 15, 2020 | Slide 37

© ABB Group
April 15, 2020 | Slide 38

© ABB Group
April 15, 2020 | Slide 39