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We discuss the evolving role of communication and control for automatic load management in electric distribution systems. We start by reprising a description of the Athens project - one of the earliest deployed examples of automatic load management at consumers enabled by communication signals. We observe that the use of communication for such systems has gone through distinct phases in its evolution...
Component derating and reconfiguration for distribution reliability is proposed in this work. Under the budget constraints postponing predictive maintenance is seen in many utilities. This practice can cause adverse effects on the performance of the utility. This work proposes a technique to improve the system reliability by derating the component with time varying hazard rate. Derating of a component...
Smart grid technologies for the high voltage power grid usually refer to (1) the new sensors that can sample voltages and currents at very fast rates and calculate their phase relationships by coordinating with aGPS time signal, (2) the high bandwidth communications that can move this voluminous measurement data to monitoring and control stations, and (3) fast controllers like breakers and power electronic...
This paper will discuss the purpose and value of energy storage as a transitional technology towards SmartGrids, as well as its utilization within the future network operational arrangements. The paper will investigate assessment techniques of energy storage at a local, system and global level, with a focus on the ways that energy storage may be valued. The paper will analyse existing techniques that...
Summary form only given. The paper presents that smart microgrid could offer a perfect power system with higher reliabilities which could guide customers to lower their costs and utilize electricity more efficiently. The task of improving the efficiency and upgrading the resiliency of the electric grid, in order to support clean and renewable energy, is one we cannot let be exported or delegated overseas...
The subject of deciding on the most appropriate method and conditions for accurately measuring the noise level of a transformer has been discussed through the transformer industry for decades. It is the objective of this Paper to contribute to this effort by identifying more appropriate conditions for both the Sound Pressure Method and the Sound Intensity Method. The Paper presents results of comprehensive...
This paper presents an efficient security assessment system for validating power system operation planning, which has been used in Henan provincial power grid in China. Daily operation planning is to schedule unit commitment and to dispatch generator output economically considering next day generators and transmission components' maintenance planning. The security assessment for validating the daily...
Because it is almost impossible to train the dispatchers with real power system, the dispatcher training simulator (DTS) is used for the training. Among various components of the DTS, the power system model (PSM) emulates the dynamic behavior of the power system to calculate the frequency and voltage. In the PSM, the power plants are modeled as differential equations, so the mechanical power of the...
The inherent variability and uncertainty of wind power generation is a major issue for countries attempting to harness large quantities of wind-based renewable energy. Such properties of wind make optimal balancing of demand and generation a much more complex task. Clearly the flexibility of thermal plant in the electrical power system is of key importance, especially in smaller systems with high...
The correction procedure for Clarke's matrix, considering three-phase transmission line analyzes, is analyzed step by step in this paper, searching to improve the application of this procedure. Changing the eigenvectors as modal transformation matrices, Clarke's matrix has been applied to analyses for transposed and untransposed three-phase transmission line cases. It is based on the fact that Clarke's...
This paper deals with a voltage and frequency controller (VFC) of a stand-alone wind energy conversion system using an isolated asynchronous generator (IAG) feeding three-phase four-wire loads. The reference generator currents are estimated using the power balance theory to control the voltage and frequency of IAG system. Two-leg reduced switch integrated voltage source converter (VSC) with a battery...
Nuclear power constitutes one of the main electricity production sources in several countries, e.g. in Sweden, with about half of today's electricity production. Driving forces for cost-efficiency have pushed the development of new methods for maintenance planning and optimization forward. Reliability Centered Asset Management (RCAM) is one of these new approaches, and maintenance optimization is...
The smart grid concept was introduced to the US utility industry by the Department of Energy (DOE). It was based on the visions of DOE's Grid 2030 and National Electric Delivery Technologies Roadmap. The debate over what constitutes a smart grid is still emerging. Nevertheless, we all agree that smart grid concept is complex and contains many interdisciplinary technologies and strategies. It is difficult...
This paper discusses modelling of high voltage AC underground cables. For long cables, when crossbonding points are present, not only the coaxial mode of propagation is excited during transient phenomena, but also the intersheath mode. This causes inaccurate simulation results for high frequency studies of crossbonded cables. For the intersheath mode, the correct physical representation of the cables...
As integration of variable generation continues to grow rapidly in power systems globally, system planners are seeking new tools to understand the role of variable output generators and the challenges experienced with their integration. The North American Electric Reliability Corporation (NERC) has established a task force to examine the integration of variable generation. This paper details the achievements...
A nonlinear adaptive neuro-fuzzy inference system (ANFIS) based controller is proposed for power electronic systems (PES) of grid connected unified doubly-fed induction generators (DFIG). The unified DFIG utilizes an additional series grid-side converter (SGSC) connected in series with the stator winding of the DFIG to inject voltage into the grid for compensation purposes. The SGSC is useful in tolerating...
Wind energy is the fastest growing source of renewable energy in the power industry and it will continue to grow worldwide as many countries are developing plans for its future development. For power system operators, this increasing contribution of wind energy to the grid poses new challenges that need to be addressed in order to ensure the reliability and security of the electric power grid. One...
Static piecewise linear models for hydro production are largely employed when a generation scheduling problem is formulated as a linear or mixed integer optimization program. Even though such models may provide a satisfactory representation of hydro generation as compared to the real nonlinear function, breakpoints of the function become natural candidates to optimal solutions of the problem. Such...
Voltage Stability Analysis has become more important as a result of insufficient reactive resources in bulk transmission systems. Usually the objective of Voltage Stability Analysis is to identify the weak regions in terms of reactive power deficiency and determine the critical contingencies and voltage stability margins for various power transfers within regions. This paper presents a practical method...
A number of states in the United States have taken collaborative actions to control for greenhouse gas (GHG) emissions from state governmental level. The effort by the western and the eastern states is called the Western Regional Climate Action Initiative and Regional Greenhouse Gas Initiative (RGGI), respectively. RGGI is a collaboration by 9 states in the northeast United States targeted at regional...
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