Project Kickoff Presentation
Energy-Efficient Signal Processing
Techniques For Smart Grid Heterogeneous
Communication Networks
Prof. Naofal Al-Dhahir
Univ. of Texas at Dallas
Prof. Brian L. Evans
Univ. of Texas at Austin
SRC GRC ICSS S7.1 Smart Grid Applications
Task ID: 1836.133
May 7, 2014
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Task Description:
Improve rate, reliability, and energy efficiency of two-way wireless and powerline
communications (PLC) between smart meters & data concentrators in smart grids
Anticipated Results:
Signal processing algorithms and real-time prototypes to demonstrate enhanced
performance of wireless and PLC transceivers for smart grids
PI/Co-PI:
Prof. N. Al-Dhahir (UT-Dallas) and B. L. Evans (UT-Austin)
Current Students (with expected graduation dates):
Ms. Jing Lin
Ph.D. (May 2014) Summer 2013 intern at TI
Mr. Karl Nieman
Ph.D. (May 2015) Summer 2013 intern at Freescale
Mr. Mostafa Ibrahim
Ph.D. (May 2017) Summer 2014 intern at TI
Industrial Liaisons:
Dr. Anuj Batra (TI), Dr. Anand Dabak (TI) and Dr. Khurram Waheed (Freescale)
Starting Date:
February 1, 2014
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
Smart Grid
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Wind farm
HV-MV Transformer
Central power plant
Grid status monitoring
Utility control center
Smart meters
Integrating distributed
energy resources
Houses
Offices
Device-specific billing
Automated control for
smart appliances
Medium Voltage (MV)
1 kV – 33 kV
Industrial plant
High Voltage (HV)
33 kV – 765 kV
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ISTOCKPHOTO.COM/© SIGAL SUHLER MORAN
Task Summary | Smart Grids | Focus | Tasks | Highlights
Smart Grid Goals
• Accommodate all generation types
• Improve operating efficiencies
Scale voltage with energy demand
Bill customer using real-time rates
Reduce peak demand (duty cycling)
Analyze customer load profiles
Analyze system load snapshots
• Improve system reliability
Monitor power quality
Disconnect/reconnect remotely
Notify outage/restoration event
Enabled by
two-way
smart meter
communications
• Inform customer
Source: Jerry Melcher, IEEE Smart Grid Short Course, 22 Oct. 2011, Austin TX USA
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Project Focus
PLC example:
transformer in USA
and rare elsewhere
Focus: neighborhood-area smart utility network between a
data concentrator and smart meters along two paths:
1) Low-voltage power lines in 3-500 kHz band
2) Unlicensed 902-928 MHz wireless band
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Task Deliverables
Date
Task
June
2015
Algorithms/software for low-complexity interference
cancellation methods that exploit channel and
interference characteristics to reduce bit error rate by 10x
Architecture/algorithm for PLC-wireless diversity
August
combining method with at least 2x improvement in
2015
energy efficiency over state of the art
January Efficient wireless coexistence mechanisms in the
2017 unlicensed 902-928 MHz frequency band
January Demonstrations on UT Austin wireless and PLC testbeds
2017
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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PLC/Wireless Diversity
• Simultaneous PLC/wireless transmissions are independent
and experience different interference characteristics
• Goal: Improve reliability of smart grid communications
using PLC/wireless receive diversity combining methods
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Unlicensed Wireless Comm. vs. PLC Systems
Unlicensed Wireless
Communications
Narrowband Powerline
Communications (3-500 kHz)
d –n/2
n is propagation constant
e – a(f) d
plus attenuation from transformers
Dynamic
Static (fixed grid topology)
Additive noise/
interference
model
Gaussian noise
Gaussian noise +
Cyclostationary interference
Asynchronous
interference
Uncoordinated users in
unlicensed bands using
same/other standards
Power electronics and
uncoordinated users
using other standards
Multi-Input
Multi-Output
(MIMO)
Enhance data rate
(spatial multiplexing) &
reliability (diversity);
Adopted in Wi-Fi and
cellular standards
Enhance data rate through spatial
multiplexing (not much diversity);
Adopted in G.9964 standard for
in-home broadband PLC
Power loss vs.
distance d
Propagation
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Wireless Coexistence Mechanisms
• Interference avoidance and/or management
• Between IEEE 802.11ah and IEEE 802.15.4g smart utility networks
in the unlicensed 902-928 MHz band
• Receiver-based: channel sensing
• Enhanced low-power algorithms that exploit signal waveform
properties
• Transmitter-based: dynamic spectrum management
• Adjust transmit power/bandwidth dynamically to reduce mutual
interference
• Long successful track record in DSL and other standards
• Goal: Enable coexistence of IEEE 802.11ah and IEEE
802.15.4g smart utility networks
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Interference Cancellation
• Interference limits performance
• Cyclostationary noise for PLC
• Period is half AC power cycle
• Spectrum varies with time
• Modeled as Gaussian noise
feeding three different filters
• Asynchronous noise in
unlicensed wireless bands
• Modeled as Gaussian mixture
• High-complexity receivers reduce bit error rates 10x-100x
• Goal: Find low-complexity methods using joint transmitter-
receiver processing with similar reduction in bit error rates
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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PLC and Wireless Testbeds
• Three PLC testbeds for earlier SRC GRC Task 1836.063
• TI PLC modems controlled by NI hardware/software
• Collected and analyzed field measurements
• Demonstrated lack of diversity for transmitting over two phases
• Freescale PLC modems controlled by PC
• Collected and analyzed field measurements
• Developed bit allocation based on previous estimates of interference
• Xilinx FPGAs controlled by NI hardware/software
• Mapped interference cancellation algorithms onto FPGAs in realtime
• Goal: Develop testbeds to evaluate communication
performance vs. complexity tradeoffs for the other tasks
SRC GRC Task 1836.133 Al-Dhahir and Evans
Task Summary | Smart Grids | Focus | Tasks | Highlights
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Project Highlights
• PLC-wireless diversity combining task
• Completed characterization of wireless link and PLC link
• Investigating diversity combining schemes based on both average
and instantaneous SNR measurements
• Low-power interference cancellation task
• PLC case: Ms. Lin completed PhD dissertation May 2014: Robust
Transceivers for Combating Impulsive Noise in Powerline Comm.
• Plans for investigating wireless case in fall 2014 and spring 2015
• Conference calls: TI (monthly) and Freescale (to start)
• Synergistic Activities
• Drs. Al-Dhahir, Batra (TI), Dabak (TI), Evans, Waheed (Freescale)
organizing 2015 IEEE International Symposium on Power Line
Communications and Its Applications in Austin, Mar. 29-Apr. 1
SRC GRC Task 1836.133 Al-Dhahir and Evans
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Thank you for your attention…
Questions?