Cognitive Radio Network for the
Smart Grid: Experimental System
Architecture, Control, Algorithm,
Security and Microgrid Testbed
Yujie Tang
Supervisor: Professor J. W. Mark
March 1st, 2012
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Introduction
Smart Grid: In a nutshell, smart grid amounts
to providing an Internet Protocol (IP) address
to every device that is connected to the
electricity grid.
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Advantages of smart grid:
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Reducing blackouts
Promoting renewable energy usage
Give families more control over their energy diet
Secure Communications in Smart Grid
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Physical layer and cybersecurity
Latency for time-sensitive data (CR)
Introduction
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Related work
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Using Cognitive Radio in the Smart Grid in [1]-[3]
Building a Cognitive Radio network testbed at
TTU, [4]: the overall picture of this project
[1]. R. Qiu, “A cognitive radio network testbed,” Proposal to Office of Naval Research
(ONR), Sep. 2010, currently funded.
[2]. R. C. Qiu, “Cognitive radio and smart grid,” presented at the IEEE Chapter,
Huntsville, AL, Feb. 18, 2010 [Online]. Available:
http://iweb.tntech.edu/rqiu/publications.htm
[3]. R. C. Qiu, “Smart grid research at TTU,” Argonne National Laboratory, Feb. 2010
[Online]. Available: http://iweb.tntech.edu/rqiu/publications.htm
[4]. R. C. Qiu, Z. Chen, N. Guo, Y. Song, P. Zhang, H. Li, and L. Lai, “Towards a realtime cognitive radio network testbed: architecture, hardware platform, and application
to smart grid,” in Proc. 5th IEEE Workshop Netw. Technol. Software-Defined Radio
White Space, Jun. 2010.
Introduction
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Main Contributions
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The application of Cognitive Radio to the Smart
Grid being addressed systemically
Applying a complex independent component
analysis (ICA) technique, in combination with
robust principle component analysis (PCA)
algorithm
Microgrid testbed: include various distributed
energy resources, different power loads or
appliances and control modules
Layered and hybrid control strategy
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Communication testbed for SG
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Hardware platforms for CRN
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Virginia Tech developed a testbed for CRN with
48 nodes.
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Each node consists of an Intel Xeon processor-based
high-performance sever, a USRP2 and a custom
developed radiofrequency (RF) daughterboard
It is not a low-power processing platform
It is not capable of mobility
Four kinds of hardware platforms
Communication testbed for SG
1. Universal Software Radio Peripheral 2 (USRP2)
Consists
of a motherboard and one or more selectable
RF daughterboard
Works with GNU radio
Has random response delay and needs multicore CPU
Communication testbed for SG
2. Small Form Factor Software Defined Radio
Development Platform (SFF SDR DP)
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Digital processing module, data conversion module and
RF module
Moved easily and full-duplex communications
Not easy to update and response time delay
Communication testbed for SG
3. Wireless Open-Access Research Platform
Development Platform (WARP)
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An FPGA (Xilinx Virtex-4 FX100 FPGA) board and one to
four radio boards
A SFF independent hardware platform, physical and MAC
Can not implement full-duplex communications
Communication testbed for SG
4. Microsoft Research Software Radio (Sora Platform)
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A radio control board (RBC) and a selectable RF board,
works with a multicore host computer
A high-throughput interface
Speedup trick is not easy, full-duplex is challenging and
lacks mobility
Communication testbed for SG
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Proposed Testbed for CRN and SG
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Performing time-critical tasks in the FPGA and
split MAC design with host and FPGA
implementations
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Ample power and upgradable
Minimum response time delay
Full-duplex communications
Proposed motherboard, functional architecture
and network testbeds
Communication testbed for SG
 Mortherboard for Hardware Platforms
Communication testbed for SG
Functional architecture
for the nodes
 Network testbed
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Communication testbed for SG
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Security of the network testbed
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The data sent out by the nodes should be
encrypted, to prevent unauthorized users from
intercepting the data over the air (cryptographic
algorithms)
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The reconfigurable FPGAs in the network testbed
should have the capability of protecting
themselves from being invaded or tampered (an
open question)
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Host computer with GPU
GPGPU: the various cores of a graphics
processor unit (GPU) can be utilized for
general purpose parallel computing
 CUDA: both a hardware and software
architecture by Nvidia
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Allows GPUs to run programs written by C, C++,
Fortran, etc
CULA is a linear algebra library which utilize to
Nvidia CUDA architecture for computational
acceleration
CULA offers more functions than GPUmat
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Microgrid testbeds for SG
 Microgrid: a localized grouping of electrical sources
and loads
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Contains distributed generators or distributed energy
sources
Increase the local reliability, reduce the power loss,
maintain the local power voltage and enhance power
utilization and efficiency
 Microgrid testbeds
 Integrated renewable or distributed energy sources, less
exchange of power
 Intelligent communications and efficiency power dispatch
 Battery and inverter technology, such as plug-in vehicles and
energy storage
Smart houses, microgrid
central controller, main electrical
power grid, one common energy
storage and common secondary
power sources
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Controller together with smart
meters: operation, maintenance,
administration and provisioning
of microgrid
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Action theory can be explored
in the microgrid central controller
to determine the trading price
and the trading quantity of
energy
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Fig. Microgrid testbeds for SG
Microgrid testbeds for SG
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Control strategy
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Layered and hybrid
Different subproblems solved by different functions
(different control layer and different control modules)
Requirement: loading balancing, electrical generation, the
limitation and efficiency of storage
The function of knowledge representation and reasoning
(means the representaion of knowledge in a manner that
helps in inferencing from knowledge)
 A presentation of related knowledge
 A cognition loop using artificial intelligence
Heuristic algorithm for the distributed control or
noncooperative control
Game theory in a complex system
Microgrid testbeds for SG
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Take one control problem in the single smart house as an
example
Fig. The total cost affected by the capacity of energy storage
Microgrid testbeds for SG
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Security consideration
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For information flow– date confidentiality, data
authenticity, data integrity, data freshness, data privacy,
public key infrastructure, trusted computing , attack
detection, attack survivability, intelligent monitoring,
cybersecurity, and so on
For energy flow– autonomous recovery is the main
security consideration
Deal with the optimization issue with uncertainty
 Robust optimization: the performance is stable with the
bounded errors
 Stochastic optimization: guarantee the performance in
average for the uncertainty information
Microgrid testbeds for SG
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Kernel GLRT for malicious data attack
[5] Y. Liu, M. K. Reiter, and P. Ning, “False data injection attacks against
state estimation in electric power grids,” in Proc. 16th Conf. Comput.
Commun. Security, 2009, pp. 21–32.
[6] O. Kosut, L. Jia, R. J. Thomas, and L. Tong, “On malicious data attacks
on power system state estimation,” in Proc. Universities Power Eng. Conf.
(UPEC), 2010, pp. 1–6.
[7] O. Kosut, L. Jia, R. Thomas, and L. Tong, “Malicious data attacks on
smart grid state estimation: Attack strategies and countermeasures,” in
Proc. 1st IEEE Int. Conf. Smart Grid Commun., Gaithersburg, MD, Oct.
2010, pp. 220–225.
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ICA for recovery of smart meter transmission
in the presence of strong interference
Outline
1. Introduction
2. Communication testbeds for Smart Grid
3. Host computer with graphics processing
4. Microgrid testbeds for Smart Grid
5. Conclusion
Conclusion
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The big picture is to sense, communicate,
compute and control
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This paper is the first to systematically investigate
the new idea of using the next generation wireless
technology, cognitive radio network, for the SG
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System architecture,algorithms and hardware
testbed are studied in detail
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A microgrid testbed is proposed
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Control strategies and security considerations are
discussed