Article
Secure and Time-Aware Communication of Wireless
Sensors Monitoring Overhead Transmission Lines
Katarzyna Mazur
1,
*
,†
, Michal Wydra
2
and Bogdan Ksiezopolski
1,3
1
Faculty of Mathematics, Physics and Computer Science, Maria Curie-Sklodowska University,
Lublin 20-031, Poland
2
Faculty of Electrical Engineering and Computer Science, Lublin University of Technology,
Lublin 20-618, Poland; m.wydra@pollub.pl
3
Department of Informatics, Polish-Japanese Academy of Information Technology, Warsaw 02-008, Poland;
bogdan.ksiezopolski@acm.org
* Correspondence: katarzyna.mazur@umcs.pl; Tel.: +48-81-537-29-38
† Current address: Pl. M. Curie-Sklodowskiej 5, 20-031 Lublin, Poland
Received: 17 May 2017; Accepted: 4 July 2017; Published: 11 July 2017
Abstract:
Existing transmission power grids suffer from high maintenance costs and scalability issues
along with a lack of effective and secure system monitoring. To address these problems, we propose
to use Wireless Sensor Networks (WSNs) as a technology to achieve energy efficient, reliable, and
low-cost remote monitoring of transmission grids. With WSNs, smart grid enables both utilities and
customers to monitor, predict and manage energy usage effectively and react to possible power grid
disturbances in a timely manner. However, the increased application of WSNs also introduces new
security challenges, especially related to privacy, connectivity, and security management, repeatedly
causing unpredicted expenditures. Monitoring the status of the power system, a large amount of
sensors generates massive amount of sensitive data. In order to build an effective Wireless Sensor
Network (WSN) for a smart grid, we focus on designing a methodology of efficient and secure
delivery of the data measured on transmission lines. We perform a set of simulations, in which
we examine different routing algorithms, security mechanisms and WSN deployments in order to
select the parameters that will not affect the delivery time but fulfill their role and ensure security at
the same time. Furthermore, we analyze the optimal placement of direct wireless links, aiming at
minimizing time delays, balancing network performance and decreasing deployment costs.
Keywords: wireless sensor networks; smart grid; overhead transmission lines; security; reliability
1. Introduction
A smart grid is an initiative to promote and transform the traditional power systems to modern
and automated power grids. An electrical power system is a set of many elements such as transmission
lines, transformers and generators connected together into a larger system, that can generate, transmit
and distribute electric power. Different kinds of electrical elements imply a large variety of dynamic
actions or responses to disturbances. Some power system disruptions can affect single element, others
can affect larger fragments. Some failures can spread and affect the system as a whole. As each
dynamic effect reflects certain unique feature of power system dynamics, some of them can be grouped
according to their cause, consequence, time frame, physical character or the place in the system that
they occur. Based on the physical character of the disturbance, different power system dynamics can be
divided into four groups, defined as: wave, electromagnetic, electromechanical and thermodynamic [
1
].
This classification also corresponds to the time frame involved (Figure 1 and Table 1). The fastest
transients are related to the wave effects or surges in high voltage transmission lines and correspond
Sensors 2017, 17, 1610; doi:10.3390/s17071610 www.mdpi.com/journal/sensors
