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Security for Resilient Power Grids in
Resource Constrained Environment
Pacome Landry AMBASSA
HPI PhD Research School in CS4A
Department of Computer Science
University of Cape Town; South Africa
mailto:pambassa@cs.uct.ac.za
10th Annual Symposium on Future Trends in Service Oriented Computing 2015
Doctoral Symposium
Hasso Plattner Institut; Potsdam, Germany
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Outline
1 Introduction
2 Micro-grid Architecture
3 Preliminary Results
Power network Monitoring
Security against energy theft
4 Conclusion
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Introduction
Introduction: Context
Low resource environment
Computational limitations
Intermittent Network
connectivity
Unstable power connectivity
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Introduction
Introduction: Motivation
Inexpensive and efficient formation and operation of so-called
micro-grids, primarily based on renewable energy to ensure fair access
or distribution of electricity to disadvantaged communities.
Re-modeling the micro-grid architecture
Incorporate portable and cheap information
and communication technology
Mobile computing devices popular in
developing countries
Inexpensive sensors with limited trust
Wireless communication technology.
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Micro-grid Architecture
Secure Resilient Micro-grid Architectures
1 Micro-grids based on distributed generation ( on renewable
including PV or wind) and network management
2 Distributed generation (mix Smaller private generators and shared
generator) across small communities
3 Fluctuations in energy production may not allow instant satisfaction
of all demand
4 Power network model
Tree topology with branches to each house
5 Communication network
Hierarchical with three layered architectures
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Micro-grid Architecture
Problem Statement...
Research Problems
1 Problem #1: Power network monitoring ...
For monitoring and controlling small-scale electricity grids to
counteract fluctuations in energy production and consumption
2 Problem #2: secure the grid against energy theft, potential fraud,
and simple mistakes,
Limited trustworthiness of metering device and unreliability of the
network
3 Problem #3: Privacy and trust in the power use
data can be used to profile individual and their behaviors:
jeopardize privacy
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Preliminary Results Power network Monitoring
Household Network
« Ambassa, Kayem, Wolthusen & Meinel , “Secure and Reliable Power Consumption Monitoring in Untrustworthy Micro-grids”, In Proc.,
First international Conference, FNSS 2015 , pp. 166-180
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Preliminary Results Power network Monitoring
Collection of home power consumption data
Idea: Use Distributed
snapshot algorithm to compute
the global state of the
household power consumption
Use a k edges spanning
tree as a communication
graph
Use delay snapshot to
collect a vector of data
measured during an interval
of time
The global state represents
the lower bound of
household’s consumption
Figure 1: Communication Tree
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Preliminary Results Security against energy theft
Errors Characterization in Power Consumption Data
Errors
Measurement Errors
Systematic errors Random errors
Maliciously Induced Errors
random false
data injection
Targeted false
data injection
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Preliminary Results Security against energy theft
Errors Characterization in Power Consumption Data
Errors
Measurement Errors
Systematic errors Random errors
Maliciously Induced Errors
random false
data injection
Targeted false
data injection
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Preliminary Results Security against energy theft
Errors Characterization in Power Consumption Data
Errors
Measurement Errors
Systematic errors Random errors
Maliciously Induced Errors
random false
data injection
Targeted false
data injection
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Preliminary Results Security against energy theft
Power Consumption Modeling
Four Category of Loads
Resistive Loads
Deterministic ON-OFF model [Barker et al.,2013]
Inductive Loads
Piecewise polynomial function
Non-linear Loads
Non deterministic and vary randomly
Composite Loads
Piecewise function
Household aggregates Loads
Function That represent the summation of individuals loads over a
time interval: Monotonically increasing function
« Ambassa, Kayem, Wolthusen & Meinel , “ Modeling and Collection of Micro-Grids Power Consumption Data in the Presence of
Adversaries”,CRITIS, May 2015,(Under review)
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Conclusion
Conclusion
Micro-grids networks are a cost effective solution for providing
access to electricity service in rural communities
Privacy, security and trust in power grids are major problems
We proposed:
Framework for a cost efficient network for power sharing in
constrained resource environment
Delay snapshot algorithm to collect individual appliance
consumption
Power consumption modeling that serves as a baseline for normal
consumption
Errors characterization in data collection
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Thank you for your kind attention !!!
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