THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

This paper discusses the state of the art in electric power system state estimation. Within energy management systems, state estimation is a key function for building a network real-time model. A real-time model is a quasi-static mathematical representation of the current conditions in an interconnected power network. This model is extracted at intervals from snapshots of real-time measurements (both analog and status). The new modeling needs associated with the introduction of new control devices and the changes induced by emerging energy markets are making state estimation and its related functions more important than ever.

Electric power system state estimation

Deregulation of energy markets, penetration of renewables, advanced metering capabilities, and the urge for situational awareness, all call for system-wide power system state estimation (PSSE). Implementing a centralized estimator though is practically infeasible due to the complexity scale of an interconnection, the communication bottleneck in real-time monitoring, regional disclosure policies, and reliability issues. In this context, distributed PSSE methods are treated here under a unified and systematic framework. A novel algorithm is developed based on the alternating direction method of multipliers. It leverages existing PSSE solvers, respects privacy policies, exhibits low communication load, and its convergence to the centralized estimates is guaranteed even in the absence of local observability. Beyond the conventional least-squares based PSSE, the decentralized framework accommodates a robust state estimator. By exploiting interesting links to the compressive sampling advances, the latter jointly estimates the state and identifies corrupted measurements. The novel algorithms are numerically evaluated using the IEEE 14-, 118-bus, and a 4200-bus benchmarks. Simulations demonstrate that the attainable accuracy can be reached within a few inter-area exchanges, while largest residual tests are outperformed.

http://www.dtc.umn.edu/s/resources/spincom8181.pdf

Distributed Robust Power System State Estimation

This paper summarizes the technical activities of the Task Force on Power System Dynamic State and Parameter Estimation. This Task Force was established by the IEEE Working Group on State Estimation Algorithms to investigate the added benefits of dynamic state and parameter estimation for the enhancement of the reliability, security, and resilience of electric power systems. The motivations and engineering values of dynamic state estimation (DSE) are discussed in detail. Then, a set of potential applications that will rely on DSE is presented and discussed. Furthermore, a unified framework is proposed to clarify the important concepts related to DSE, forecasting-aided state estimation, tracking state estimation, and static state estimation. An overview of the current progress in DSE and dynamic parameter estimation is provided. The paper also provides future research needs and directions for the power engineering community.

/pdf/power-system-dynamic-state-estimation-motivations-lul365qej6.pdf

Power System Dynamic State Estimation: Motivations, Definitions, Methodologies, and Future Work

This article provides a survey on state estimation (SE) in electric power grids and examines the impact on SE of the technological changes being proposed as a part of the smart grid development. Although SE at the transmission level has a long history, further research and development of innovative SE schemes, including those for distribution systems, are needed to meet the new challenges presented by the requirements of the future grid. This article also presents some example topics that signal processing (SP) research can contribute to help meet those challenges.

/pdf/state-estimation-in-electric-power-grids-meeting-new-otnl668ac3.pdf

State Estimation in Electric Power Grids: Meeting New Challenges Presented by the Requirements of the Future Grid

A taxonomy of multi-area state estimation methods

SIME: A hybrid approach to fast transient stability assessment and contingency selection

A study was conducted on the extra high voltage (EHV) French power system in order to explore the extended equal-area criterion and test its suitability as a fast transient stability indicator. The assumptions underlying the method are reexamined, causes liable to invalidate them are identified, and indices are devised to automatically circumvent them. The selection of candidate critical machines is also reconsidered, and an augmented criterion is proposed. The various improvements were developed and tested on about 1000 stability scenarios, covering the entire 400 kV system. The severity of the scenarios, resulting from the combination of weakened pre and post-fault configurations, subjected the method to particularly stringent conditions. The simulation results are summarized. >

Extended equal area criterion revisited (EHV power systems)

Synchronized phasor measurement units (PMUs) are becoming a reality in more and more power sys- tems, mainly at the transmission level. This paper presents, in a tutorial manner, the benefits that existing and future State Estimators (SE) can achieve by incorporating these de- vices in the monitoring process. After a review of the rele- vant PMU technological aspects and the associated deploy- ment issues (observability, optimal location, etc.), the alter- native SE formulations in the presence of PMUs are revis- ited. Then, several application environments are separately addressed, regarding the enhancements potentially brought about by the use of PMUs.

Patricia Rousseaux

Papers

A taxonomy of multi-area state estimation methods

SIME: A hybrid approach to fast transient stability assessment and contingency selection

Extended equal area criterion revisited (EHV power systems)

On the use of PMUs in power system state estimation

Whither dynamic state estimation