SST-Sensor Network Design For A Secure National Electric Energy Infrastructure

The events of September 11, 2001, have highlighted the impact of malicious attacks on critical national

infrastructure components. This has resulted in an increased appreciation for improving the physical security of

critical electric power system components like substations, transmission lines, and generators. These observations

together with the major North East blackout of August 14 th , 2003 highlight the importance of the electric grid as an

energy transport medium and its critical importance to the nation's economy and global competitiveness.

The electric power grid is a highly automated network. A variety of information networks are interconnected to the

electric grid for the purpose of sensing, monitoring, and control. Any disturbance or dislocation in the electric

network is sensed primarily by observing the electrical behavior of the power system via the observations and

analysis done using the data obtained using measurements of electrical quantities. The sensor technology that

aids the deployment of distributed sensing systems has improved vastly in the recent past. However, even though,

standards do exist for physical security of substations, very few modern sensing mechanisms have been utilized to

meet the physical security standards.

With this scenario in mind we will undertake the following research in the sensing and information processing of the

electric grid: (1) examine new sensors to sense physical quantities in power systems; (2) design a wireless sensor

information network to transmit these measurements to the central control center; (3) develop algorithms for sensor

placement, data aggregation, fault diagnosis, and load balancing for the sensor information network; and (4) fuse the

physical sensor data with conventional electrical sensor data to devise more effective control strategies following

large disturbances. We will demonstrate the developed techniques and validate them on a test bed that we have

created to emulate a large power system using an operator training simulator. The key elements of the proposed

approach consist of the following steps:

1. Design structure of the wireless sensor information network that maintains connectivity under a variety of

contingency scenarios in two modes, a) Partial mode that helps in detection of failures, and b) Full mode which

helps in diagnosis of the problem.

2. The sensor network in Partial Mode will be used to zero in on portions of the power grid where the system

would like to get physical sensor information to fuse with existing electrical sensors to detect disturbance, and

or catastrophic failures based on: a) On-line risk based engine, b) Unusual or abnormal measurements from

certain sensors like temperature, motion, or chemical sensors, or c) Weather and unusual conditions.

3. This leads to a decision on transferring to Full Mode operation where more information collection via sensor

activation and deactivation, communication network connectivity, and power usage considerations will be made

from the critical local portion of the power grid identified by the above analysis.

4. This information leads to further diagnosis of the network condition that is used by central control center to

invoke appropriate control action to safeguard the power network.

Intellectual merit of the proposed research lies in developing novel concepts for integrating a broad range of

sensors that monitor both physical security and operational security of the nation's most critical infrastructure the

electric grid. The project aims at using the combined data from these sensors together with the detailed development

of the associated communication and information network to enhance the security and reliability of the power grid.

The team has combined their expertise to take a fresh view at the different kinds of sensors currently available and

extract appropriate data from them for several key issues related to power system physical security.

The broader impact of this research will be two fold. First, it will enhance the state of art in sensing, monitoring,

and controlling the electric power grid by combining the multidisciplinary expertise of the investigators. Second, the

new sensor network will be applied to develop an emergency response system for the national electric grid, which is

essential to the vitality of the nation's economy, and will provide protection to it.

Education: Our educational goal is to train the next generation of students, train new cadres of doctoral researchers

and most importantly, share the excitement that comes with working in engineering with the youngest of students, in

the K-12 program, to attract them into science and engineering. The college of engineering at Iowa State University

has a dedicated effort to attract minority scholars into the graduate program and the university has an ongoing

program to employ high school students and teachers in research programs during the summer. We will leverage

these efforts.