Feb 20, 2013 - responses from milliseconds to tens of minutes. by organizing the control actions into a hierarchy, a continuous range of response can be ...
responses from milliseconds to tens of minutes. By organizing the control actions into a hierarchy, a continuous range of response can be achieved. The next chapter explores graph theory as a tool for prioritizing power grid buses and lines for intervention. Authors Wang, Scaglione, and Thomas propose a centrality measure specific to the power grid incorporating electrical impedance characteristics in addition to the network topology. Centrality measures are used to study network properties and identify the most important elements. These critical portions of the network can then be hardened to lessen vulnerability to attack and enhance system robustness. The final section of the book contains chapters on communications and control. The chapter by Ma, Callaway, and Hiskens develops strategies to coordinate plug-in electric vehicle charging. Centralized and decentralized approaches are presented to optimize charging costs. The centralized approach is used to show that the valley filling charging approach is globally optimal. These problems are formulated as large-population games on a finite charging interval. The authors note that the traditional game theory Nash equilibrium is difficult to achieve if electricity price is the sole optimization objective. The section on communications and control would not be complete if it did not include an analysis of cyberattacks on the power grid. Srikhar, Govindarasu, and Liu describe attack scenarios in which the security of the power grid could be severely compromised. The authors assess the risk associated with brute-force and intelligent attacks, both isolated and coordinated. They introduce a probability of successful cybernetwork intrusion and impact on the power system. Their results indicate the significant factors that impact attack severity are network topology, location of attack targets, and the criticality of the component. The chapter by Haughton and Heydt describes the process by which synchronous measurements are obtained and how they can be used to improve the state-estimation process. By using a time march/april 2013
stamp of a GPS, it is possible to obtain a least squared error fit of a phasor to a sinusoidal waveform, yielding positive, negative, and zero sequence voltage and current components. By using synchronous measurements, the state estimation process can be simplified since the complex (phasor) formulation is linear. State estimation at the distribution level can lead to better control, fault management, and energy management. The effect of communication time delays is again discussed in the chapter by Zhang and Chow but with respect to a decentralized adaptation of the economic dispatch problem. Of particular interest is the use of consensus algorithms to coordinate the actions of distributed controllers. Without time delays, controllers can coordinate their actions by comparing their known system states, and discrepancies can be rapidly identified. In the situation of time delays, the system states are seldom consistent, and this adds additional complexity to the control problem of achieving consensus of the system state. This extra complexity potentially adds additional time delays since the controllers may take longer to converge to a consensus. The chapter by Chow and Ghiocel presents an adaptive wide-area interarea mode damping controller using PMU synchrophasor data. The authors show that the additional data provided by the PMUs increase the observability of the system, rendering greater controllability. They also note that the communication delay and computational burdens may add data latency that degrades control performance. The authors propose an adaptive control scheme to counter this variable PMU data latency by adaptively varying the amount of phase-lead compensation in the network. The book is rounded out by the final chapter by Prof. Chakrabortty on interarea modal damping using synchronized phasor measurements. He proposes three steps: model reduction, control aggregation, and control inversion whereby the aggregate control action is divided and distributed to local decentralized controllers. The model reduction step is aided by using the
PMU data to identify oscillation clusters about which the equivalent models can be aggregated. Feedback control is applied to this reduced model to obtain an aggregate control signal, which is then deconstructed to provide individual control signals. This approach provides a scalable approach to using PMU data for control. —Mariesa Crow
Grid Integration and Dynamic Impact of Wind Energy By V. Vittal and R. Ayyanar Perhaps the most significant avenue of endeavor in the power and energy industry today is the pursuit of sustainability of energy sources and the continuous drive for greater energy efficiency both in its utilization and conversion. Nowhere is this more apparent than in the application, research, and development of wind and solar energy systems. On the political scene, state government legislation in many regions has put into place renewable portfolio standards, which continue to push for increased utilization of renewable resources. This is a major factor that has meant a tremendous rise in the integration of wind power plants, and more recently photovoltaic energy systems, throughout North America. The trend, needless to say, is a global one. With these factors, it is clear that both the practicing electrical engineer and the student must have a working knowledge of the application, modeling, and dynamic performance of wind energy systems. As such, congratulations are in order for the authors on what is a welcome addition to the body of literature in this field. The book constitutes a very nice and concise treatment of wind energy systems and their dynamic behavior in the context of large integration into the bulk electric power system. It is quite an easy read and yet quite comprehensive in its treatment of some of the basic and fundamental theory behind the design and control of power electronic based wind energy systems. Digital Object Identifier 10.1109/MPE.2012.2232774 Date of publication: 20 February 2013
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the salient points related to fault ridethorough. This should not be perceived as a criticism since the book is an introductory text and does not presume to elaborate on all the intricate details of the latest technology. Chapter 4 provides comprehensive coverage of the basic control philosophy of the doubly fed asynchronous generator. It is a quite refreshing treatment, and both the steady-state and dynamic equivalent circuit models for a doubly fed machine are derived from first principles to give a thorough understanding of the physical behavior and characteristics of the machine. It is impressive that the mathematical treatment is quite practical, focusing more on the engineering and physics of the device and less on the mathematical formulation. This is an excellent approach and of great value to any student or practicing engineer. The chapter does not delve into similar details for the full-converter wind energy systems. For future editions, more detailed coverage of the type 4 units will be welcome. Chapter 5 provides a good summary of the latest publications related to the development of dynamic models for wind turbine generators, particularly of “generic” and standard models. The chapter pulls much of its material from documents published in CIGRE, IEEE, and WECC and by one of the wind turbine manufacturers. The authors have done an excellent job in summarizing this literature in a way that is easily comprehensible while still conveying the key and critical points of the
subject. One comment is that both the technology and the models are continuously evolving, and the second generation of generic models are well on the way to being released through efforts in WECC and IEC, and so this chapter could be updated in future revisions. The last chapter, Chapter 6, provides a broader overview of the various dynamic performance issues encountered for large-scale penetration of the wind power plants, based on doubly fed asynchronous generator technology, into the bulk power system. Subjects such as small-signal stability, transient rotor angle and voltage stability, system frequency response, and voltage ride-through are all discussed, together with simulation examples. This is the chapter where all the material comes together and is both well written and a valuable source of information for the researcher, student, and practicing engineer. The chapter focuses only on the type 3 wind turbine generators, but much of what is discussed can be extended to the type 4 wind turbine generators. There is no coverage of the impact of type 1 and 2 wind turbine generators on system dynamic performance, but this can be found in several of the references quoted in the book. In summary, I wholeheartedly en joyed reading the book and without hesitation highly recommend it to all. It is a must read for any electrical engineering student and a great reference for practicing engineers. I commend the authors on an excellent book. —Pouyan Pourbeik p&e
John Pierre
James Charles Smith
Leon Tolbert
For development of signal processing methods for estimation of powersystem stability.
For leadership in integration of wind energy sources into the electric power grid.
For contributions to multilevel power electronic converter technology.
Kameshwar Poolla
Marc Stubbe
For contributions to system identification, robust control, and applications to semiconductor manufacturing.
For contributions to power system analysis and simulation techniques.
For contributions to power electronic applications to renewable energy systems.
Chapter 1 is a well-written introduction and provides a good summary of the various wind generation technologies. The two diagrams showing the power exchange mechanism on the doubly fed asynchronous generator technology were quite delightful and are an excellent educational tool to introduce this technology. Many of the diagrams and graphical presentations in the book are extremely effective in communicating some complex concepts. Chapter two is a concise yet comprehensive treatment of power electronic converter technology. The chapter covers the basics of single, double, and threepole converters and provides a practical mathematical treatment of the subject, explaining how one can derive the wellknown “average model” for power converter circuits. This is an essential read for those new to the area of wind and solar energy systems since most of the technologies in today’s market interface to the grid using power converters. Chapter 3 is an overview of the converter topologies for doubly fed (type 3) and full-converter (type 4) wind turbine generators. As indicated earlier in the book, older wind turbine technologies are not covered in any detail, the conventional induction generator (type 1) and wound-rotor induction generator (type 2). This is perhaps not too inappropriate since the industry trend is toward more modern technologies. The discussions in this chapter related to the performance of the power electronic converters under fault conditions is limited and only touches on some of
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