This project examines the application of phasor measurement units (PMUs) for on-line transient stability assessment in an operational decision-making environment. The primary motivation for the project arises from the critical need to develop analytical tools to enhance power system reliability, from the goal to provide superior operational situation awareness using accurate real-time measurements, and from the search for innovative applications for measurements made using PMUs.

Final report for PSERC project "A Tool for On Line Stability Determination and Control for Coordinated Operations between Regional Entities Using PMUs" (S-27). Uploaded: January 10, 2008.

In recent years, renewed emphasis has been placed on vegetation management of transmission right-of-way to avoid tree contacts that could put system reliability at risk. At the same time, new approaches to vegetation management have been sought to be able to achieve the needed tree clearances as cost-effectively as possible. One possible approach is to process satellite images to prioritize tree maintenance work. For this approach to work, new computational tools will be needed to convert satellite image data into useful information for vegetation management scheduling. This project's objective was to develop such computational tools for determining the location of trees interfering with overhead transmission lines. The input data were derived from satellite images, and the GPS coordinates and altitudes of transmission towers. The tools determine the location of healthy trees that are penetrating a danger zone or safety envelope (e.g., 20 ft. radius) surrounding the conductors.

Final report for PSERC project "Satellite Imagery for the Identification of Interference with Overhead Power Lines" (T-28). Uploaded: January 15, 2008.

All-digital systems for measurement, protection, and control with components from different manufacturers are increasingly being deployed in electric power substations. As this occurs, a critically important task becomes the verification that required performance and expected design criteria are satisfied for any specific system configuration and interdevice communications standard. Of particular focus in this research is the development of a methodology for testing device interoperability under the International Electrotechnical Commission (IEC) Standard 61850-9-2 on communication interfaces in substations.

Final report for PSERC project "Digital Protection System Using Optical Instrument Transformers and Digital Relays Interconnected by an IEC 61850-9.2 Digital Process Bus" (T-29). Uploaded: January 29, 2008.

Cascading outages in power systems are costly events that power system operators and planners actively seek to avoid. Such events can quickly result in power outages for millions of customers. Although it is unreasonable to claim that blackouts can be completely prevented, we can nonetheless reduce the frequency and impact of such high consequence events. Power operators can take actions if they have the right information provided by tools for monitoring and managing the risk of cascading outages. Such tools were developed in this research project by identifying contingencies that could initiate cascading outages and by determining operator actions to avoid the start of a cascade. Power system planners can also take actions if they have knowledge of the effects of transmission investments on the risk of cascading blackouts. In this project, system risk assessment tools were developed to estimate the overall risk of cascading transmission line overloads. The goal of this line of research on the risk of cascading outages is the creation of new tools that power system operators and planners can use to enhance system reliability.

Final report for PSERC project "Risk of Cascading Outages" (S-26). Uploaded: February 27, 2008.
Part A Project Leader: Jim McCalley, Iowa State University. Part B Project Leader: Ian Dobson, University of Wisconsin-Madison

The operational security of the power system depends upon the successful performance of the thousands of relays that protect the system from cascading failures, that protect equipment, and that help balance load with generation when system frequency is too low or too high. The failure of a relay to operate as intended may jeopardize that stability of the entire system and equipment in it. In fact, major system failures after a disturbance are more likely to be caused by unintended protective relay operation rather than by the failure of a relay to take an action at all. Appropriate relay testing provides one line of defense against relay failures. Relay testing improvements need to continue because of the new demands placed on relays from power system conditions that are more variable in the past, because of high customer expectations for power delivery reliability, and because of changing relay technologies.

Final report for PSERC project "Transient Testing of Protective Relays: Study of Benefits and Methodology" (T-30). Uploaded: April 10, 2008.

In recent years, new attention has been given to use of volt-amperes reactive (VAR) resources to support power system operation. The engineering questions are how much VAR resources are needed, where should they be located, and what should the allocation be between static VARs that provide constant VARs and dynamic VARs that can be controlled in real-time. The project's objectives were:

(1) to develop realistic models that accurately model system dynamics and capture voltage recovery phenomena,
(2) to develop criteria for selection of the optimal mix and placement of static and dynamic VAR resources in large power systems based on modeling results using the tools developed part, and
(3) to create a unified optimization model for minimizing the deployment of static and dynamic VAR resources while meeting the criteria.

The project was accomplished in five integrated steps described in the four volumes of this report. A fifth volume is still being prepared and will be distributed separately. A test system provided by Entergy was used as a common platform to test the tools.

Final report for PSERC project "Optimal Allocation of Static and Dynamic VAR Resources" (S-24). Uploaded: April 1, 2008.
Volume 1 Project Leader: Vijay Vittal, Arizona State University; Volume 2 Project Leader: V. Ajjarapu, Iowa State University; Volume 3 Project Leader: Jim McCalley, Iowa State University; Volume 4 Project Leader: Sakis Meliopoulos, Georgia Tech

Currently large amounts of data are collected by Intelligent Electronic Devices (IEDs) at the substation level. Beyond the traditional Supervisory Control and Data Acquisition (SCADA) data collected by Remote Terminal Units (RTUs), very little of other IED data is integrated into current Energy Management System (EMS) solutions. The goal of the project is to investigate the potential benefits of integrating information obtained from the substation IED data, beyond what is obtained from RTU data, into the EMS. This report describes development of the software aimed at automated fault location analysis and visualization. A complete system for automated fault location (FL) analysis including visualization of results and behavior of equipment is developed.
Concurrent Technologies Corporation Final Public project report.

Final report for PSERC project "Optimized Fault Location: Integration of Substation IED Information into EMS Functionality" (T-32). Uploaded: April 11, 2008.

Visualization of power system conditions can help power system operators maintain adequate situational awareness. This project’ s purpose was to perform research to increase the effectiveness of power system visualizations, with a particular emphasis on visualization used in the control center environment. Six areas where specific research accomplishments were attained in this project include: A new power system visualization approach, known as geographic data views, to provide better visualizations for use during operator initiated power system control and for engineering analysis; Two new approaches to reduce the time needed to produce power system contours; A technique for using phasor measurement unit (PMU) data to determine status changes of devices such as transmission lines and generators; Direct visualization of the voltage angle information being provided by PMUs; Insight and analysis on the human factors aspects of power system visualization; Use and visualization of GPS synchronized data for power system stability assessment.

Final report for PSERC project "Effective Power System Control Center Visualization" (S-25). Uploaded: May 28, 2008.

A public good is a shared commodity, like a street sign, such that use by one person does not reduce the enjoyment of another person. Unlike private goods, use is not exclusive which leads to free-riding, where a benefactor of a service does not pay for it, and under-provision. To explore the issue of public goods in the context of an electric energy supply and delivery system, this work:

• Lays out an appropriate conceptual framework for analyzing power markets using an economic/engineering model of optimal investment and operation,
• Provides simulations and experiments that show both an ideal system and the potential for market power in real time markets,
• Draws research conclusions, and
• Makes specific recommendations for market structure and operation that properly take into account the need for reliability.

Final report for PSERC project "Reliability, Electric Power, and Public Vs. Private Goods: A New Look at the Role of Markets" (M-12). Uploaded: July 29, 2008.

This is a final project report for research on the subject of massive deployment of sensors in electric power systems. There are several areas where the addition of modern, economical sensor technology can improve the quality of a large electric power grid. This report provides a quick reference for a variety of applications of massively deployed sen-sors (along with the advancement of communication and computer technology) that are currently being used and are also in the research and development stage. The report spans a wide spectrum of instrumentation technologies, largely correlated to the several forms of energy, namely electric, magnetic, atomic, chemical, kinetic, and potential.

Final report for PSERC project "Massively Deployed Sensors" (T-31). Uploaded: August 22, 2008.

Incentives for attracting investments in transmission assets are essential to the overall success of the restructuring of the electric power industry. In general, adequate transmission capacity enhances reliability, lowers energy cost as delivered, limits market power of market participants, and provides flexibility to protect against market uncertainties such as load fluctuation, fuel price volatility, and unexpected facility outages. Various transmission-pricing approaches have been developed for recovering transmission costs and providing incentives for future expansion or enforcement. According to the market-based investment model, a transmission investment usually expands power-transfer capability, and therefore, increases the quantity and variety of transmission rights can be issued to investors. This project tackles problems related to the evaluation of market-based schemes for compensating transmission investments.

Final report for PSERC project "Evaluation of Alternative Market Structure and Compensation Schemes for Incenting Transmission Reliability and Adequacy Related Investments" (M-11). Uploaded: August 27, 2008.

Countries around the world continue to refine their electricity market structures in various ways. There are ongoing debates over market design issues, such as how to design effective market power mitigation rules, how to incorporate ancillary service markets, and how to properly implement a retail electricity market to encourage customer participation. Although valuable experience has been gained, there is a lack of a robust analysis platform for evaluating the effects of a new market design from both engineering and economic points of view. The difficulty in creating such a platform arises from the interactions among strategic behaviors of market players, various layers of market designs, and the underlying physical network. A multi-agent system with a corresponding software platform would allow for robust analysis of the complex phenomena of an electricity market with its human decision-making in the context of market rules and a physical electric system. In this research, multi-agent electricity market simulation tools were designed and implemented. Three market design areas were investigated: market power mitigation, ancillary service market design, and customer participation.

Final report for PSERC project "Agent Modeling for Integrated Power System, Power and Fuel Market Simulation" (M-13). Uploaded September 4, 2008.

When a power system is subjected to large disturbances control actions need to be taken to steer the system away from severe consequences and to limit the extent of the disturbance. This is particular true if system is in an operating condition that makes it unusually vulnerable to catastrophic failure. In a previous PSERC project (S-19 that ended in 2005), we developed novel algorithms for each of the following steps:

(1) Detection of major disturbances and protective relay operations leading to cascading events. The detection algorithms improved capabilities of real-time fault detection and analysis to classify the impact of a fault towards initiating cascading outages.
(2) Wide-area measurement based detection and remedial control actions. The wide-area mitigation algorithms include methods for reliably extracting modal information on critical wide-area modes through real-time wide-area Phasor Measurement Unit (PMU) measurements. They also provide specific control actions to damp out the oscillations when problems are detected.
(3) Adaptive islanding with selective under-frequency load shedding. The adaptive islanding algorithms suggest methods for controlled islanding of the system should mitigation strategies fail.

The algorithms were shown to be effective using realistic computer models of test power systems. In this project, we focused on prototype implementations of those algorithms at collaborating PSERC member utilities.
This report has three parts:
Part I: Detection of Major Disturbances and Protective Relay Operations Leading to Cascading Events;
Part II: Wide-Area Measurement Based Detection and Remedial Control Actions; and
Part III: Adaptive Islanding with Selective Under-Frequency Load Shedding.

Final report for PSERC project "Detection, Prevention and Mitigation of Cascading Events – Prototype Implementations" (S-29). Uploaded September 19, 2008.
Part 1 Project Leader: Mladen Kezunovic, Texas A& M University; Part 2 Project Leader: Mani V. Venkatasubramanian, Washington State University; Part 3 Project Leader: Vijay Vittal, Arizona State University

In recent years, new attention has been given to system disturbances that have cascaded due to voltage instabilities and to unwanted relay operations. Unwanted relay operations due to voltage instabilities and transients have not been well understood. In this project, voltage instability phenomena were studied to develop a comprehensive approach for mitigating the effects of voltage transients and instabilities on designed operation of a protection system. The comprehensive framework covers monitoring, predicting, and assessing system performance for secure power system operation. The developed framework and methodology provide advanced tools use optimal control strategies that can be used to avoid voltage collapse with respect to system-wide voltage instability and undesired protection system operations. The project's specific objectives were:

(1) to develop realistic models that accurately model voltage dynamics and their effects on protective schemes;
(2) to develop fast and flexible schemes for assessment of voltage stability and relay status; and
(3) to develop optimal strategies to prevent voltage instability and maintain adequate relay margins.

Final report for PSERC project "Reactive Power Planning against Voltage Collapse with respect to Undesirable Component Protection" (S-28). Uploaded: October 3, 2008.

This project developed a computational tool for analyzing offers into auctions. The tool has two major applications. First, market monitors can employ it to assess the competitiveness and efficiency of offers by comparing the actual offer of a market participant to a hypothetical perfectly competitive offer and to an ex post profit maximizing offer. Such analysis can be useful to market monitors who seek to evaluate the behavior of a particular market participant. Second, the tool can assist market participants, especially the smaller ones, in the formulation of offers in the face of the strategic complexity facing them. The tool and associated graphical user interface allows the ex post profit maximizing offer for a firm to be constructed on the basis of information about the aggregate offers of other market participants, the firm's own cost function, and zonal transmission constraints.

Final report for PSERC project "Tools for Assessment of Bidding into Electricity Auctions" (M-15). Uploaded: October 31, 2008.

Operational data are used in energy management systems by power system operators to monitor and control the power system. This project's objective was to explore the potential benefits of integrating non-operational and situation awareness data into an energy management system. The project focused on three major tasks:

• Identify properties of data collected by IEDs
• Specify how an energy management system could use non-operational and situation awareness data and the benefits of doing so
• Outline new design approaches for future energy management system functionality using fault location, topology processing, alarm processing, and operator displays as examples.

Final report for PSERC project "Optimized Fault Location: Integration of Substation IED Information into EMS Functionality" (T-32). Uploaded: November 10, 2008.

This research project presents and examines an online voltage security assessment scheme to evaluate post-contingency voltage security in real time by using synchronized phasor measurement units (PMUs) and periodically updated decision trees (DTs). The main objective is to develop a fast and accurate tool to predict whether certain severe contingencies will initiate voltage collapse at the current operating condition for the purpose of preventing voltage collapse in a modern power system. The online assessment results are then used to guide system operators in real-time decision making. This project involved the participation of a PSERC member company - American Electric Power (AEP) Corporation - that provided supplemental funding for the project and the associated data, and participated as an industry advisor to the project.

Final report for PSERC project "A Tool for On Line Stability Determination and Control for Coordinated Operations between Regional Entities Using PMUs: Expanded Testing - Decision Tree Based Online Voltage Security Assessment Using PMU Measurements" (S-27G). Uploaded: November 12, 2008.