IEEE Communications Magazine • May 2012
142
0163-6804/12/$25.00 © 2012 IEEE
INTRODUCTION
The ever increasing global population imposes
demanding requirement on the electric power
supply. Nevertheless, the global warming and the
sustainability of the cities render constraints on
the power generation by the traditional environ-
ment-hostile power plants. Viable measures for
supporting the continuously increasing global
economy is to upgrade the current power grid to
a smarter grid. The smart grid can deal with the
problem by two strategies. One is to improve the
efficiency of the current power grid through
smartly managing the production, distribution
and consumption of electricity. The other is to
incorporate the renewable energy resources, like
solar, tide and wind sources, into the whole
power grid. The green energy lowers the energy
price and reduce the greenhouse gas emission.
To achieve above goals, the technologies,
including communication technologies, net-
worked control and optimization technologies
have to be incorporated into the energy manage-
ment system (EMS). A fundamental part of such
a system is a wide area monitoring system
(WAMS) based on a comprehensive communi-
cation network [1], including sensor network,
WiFi, satellite communication, cellular network,
and Internet, etc. The communication network is
responsible for information collection and con-
trol message transmission, especially when the
volatile renewable energy sources are connected
to the smart grid. The knowledge of the state
information enables the grid operators to adapt
their power production and distribution dynami-
cally in real-time. Unlike the communications in
the traditional power grid, in the smart grid the
ubiquitous communication network extends the
system monitoring and control to the end-user
level. The end users will be liberated to choose
different power suppliers or manipulate their
energy usage dynamically. For example, the
General Electric’s (GE’s) smart-grid refrigerator
can reduce the consumption significantly by
adjusting its working cycle as response to the
price signal from the smart grid.
Two types of important nodes in the smart
grid are the phasor measurement unit (PMU)
and the smart meter (SM). The PMU was first
invented at Virginia Tech. Nowadays there are
less than 200 PMUs deployed distributedly in
ABSTRACT
An efficient dependable smart power grid
relies on the secure real-time data collection and
transmission service provided by a monitoring
system. In such a system, the measuring units,
such as phasor measurement units (PMUs) and
smart meters (SMs), are critical. These measur-
ing equipments function as sensors in the smart
grid. Data exchanges between these sensors and
the central controller are protected by various
security protocols. These protocols usually con-
tain computationally intensive cryptographic
algorithms that cause heavy energy overhead to
the sensor nodes. Since PMUs and SMs are
mostly energy-constrained, the problem of how
to ensure the secure communication with mini-
mum energy cost becomes a critical issue for the
functionality of the whole smart grid. In this arti-
cle, we focus on the low power secure communi-
cation of the PMUs and SMs. We take two
wireless sensor platforms as examples to experi-
mentally investigate the approaches and princi-
ples of reconciling the two conflicting system
requirements–communication security and low
energy consumptions. The proposed methods
are general ones and applicable to other energy-
constrained yet security sensitive systems.
COMMUNICATION PROTOCOLS AND
ALGORITHMS FOR THE SMART GRID
Meikang Qiu, Huazhong University of Science and Technology and University of Kentucky
Hai Su, University of Kentucky
Min Chen, Huazhong University of Science and Technology and St. Francis Xavier University
Zhong Ming, Shenzhen University
Laurence T. Yang, Huazhong University of Science and Technology and St. Francis Xavier University
Balance of Security Strength and
Energy for a PMU Monitoring System in
Smart Grid
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