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Installation of a large number of small sources called distributed generation creates many problems in proper control of national (and European) power grid. At the same time new technologies especially power electronics and measurement data computing associated with smart grid allows to use better and conscious these distributed sources. This paper describes what problems the distributed generation...
When analyzing the quality of electrical power delivered to customers many parameters are considered. However the fundamental issue is the presence of voltage and its reliability and continued presence. Power systems all over the world experience big power failures from time to time leading to a total lack of voltage over a large area - called blackouts. This paper presents an automated method for...
The probabilistic reliability evaluation of composite power systems is a complicated and computation intensive task. Monte Carlo Simulation (MCS) is often used as the method of choice for tackling this difficult problem, though MCS may also suffer from issues regarding high dimensionality leading to an increased need for computational resources. In order to address this issue an algorithmic method...
With the fast development of the power systems, the expanding of the power system is bigger, and users have the higher requirements of the electric quality, so researches and developments in electric power systems analysis has been an area of significant activity for decades. The robustness of a power system is measured by the ability of the system to operate in a state of equilibrium under normal...
This paper points to some ways in which concepts of ‘security’ might be revised in order to more cost-effectively accommodate new generation and wider market interactions without undue increase in system unreliability. The background to ‘security standards’ and the scope for change are discussed. A number of issues are cited that are likely to make the achievement of a theoretical ideal very difficult...
Massive blackouts of electrical power systems over the past decade has focused increasing attention to cascading events that may lead to widespread network collapses. It is important to be able to identify places in the system where the cascading events are most likely or/and lead to the most severe consequences. Based on this information, transmission planning decisions can be made that minimize...
Cascading failures typically involve a wide variety of power system dynamic phenomena, including cascading transmission line overloads, generator tripping, voltage collapse and/or rotor dynamic instability. Metrics that estimate proximity to critical points with respect to any of these phenomena could be useful as indicators of cascading failure risk. With the growing deployment of phasor measurement...
The power output from wind farms is highly volatile, uncertain and hard to be predicted accurately. Then sometimes positive short-run correlation between variations of wind power output and load could bring more and larger disturbances in the system operation, bringing reliability and economic concerns. The integration of wind power generators in power systems poses some challenges, and besides installing...
Hawaii Electric Light operates an autonomous power system on the island of Hawaii with a diverse mix of generating resources. Although the system is small, with an annual peak in 2009 of less than 200 MW, the power system balancing and frequency control is provided through a conventional centralized Automatic Generation Control system. The mix of generation resources on the Hawaii Electric Light System...
We introduce a new microscopic model of the outages in transmission power grids. This model accounts for the automatic response of the grid to load fluctuations that take place on the scale of minutes, when the optimum power flow adjustments and load shedding controls are unavailable. We describe extreme events, initiated by load fluctuations, which cause cascading failures of loads, generators and...
This paper describes an alternative method, derived from a simulation model, for expansion planning for grids considering wind turbine generators in a composite power system. The proposed model includes capacity limitations and uncertainties of the generators and transmission lines. It proposes to handle the uncertainties of system elements (generators, lines, transformers and wind resources of WTG,...
Renewable intensive bulk power system planning and operation considerations are getting high importance due to huge pressure imposed by environment-friendly policies and uncertainties in the fossil-fuel based investments. This paper addresses a number of influential economic and reliability issues for renewable generation entry to a deregulated electricity market. Geothermal power penetration, wind...
Work has recently been completed that improves the computational aspects of Monte Carlo simulation (MCS) including its total computational time and iterations required for convergence through the use of a novel technique known as state space pruning. This methodology currently exists in two distinct flavors: The analytical method and a method built on Population-based Intelligent Search (PIS) techniques...
After 2003 blackout, wide area measurement, monitoring, and visualization become one of the most important areas of smart grid initiative. Synchrophasors are precise time-synchronized measurements of certain parameters on the electricity grid, now available from grid monitoring devices called phasor measurement units (PMUs). Phasor data and applications are valuable for grid reliability because they...
The utilization of renewable sources in power generation and system deregulation are two major changes the power system are undertaking. Different evaluation models are needed in order to incorporate renewable generation in the existing power system analysis. In deregulated power system, the impacts of renewable generation penetration are not only on the physical operation, but also on economic operation...
Considering the variation and intermittence caused by the high penetration of wind power, more additional operational reserves are required to keep the balance of power energy. With the development of wind prediction technology, more accurate operational reserves can be calculated among different time scales, from microseconds to days. Several methodologies for computing operational reserves are summarized...
With distributed generation technologies becoming more and more sophisticated and the progressive development of distribution automation technology, the application of distributed generation in distribution power system is gradually broad and diverse. This paper first lists the common operation modes of distributed energy sources, then analyzes the different characters of distributed generation running...
Intermittent and uncertain nature of power output from weather-dependent renewable energy sources like solar is a major challenge in integrating them with traditional power grids that mostly consist of reliable power sources. We have created a framework for efficiently managing the weather-related uncertainty risk of solar generators and facilitating their integration into power grids while optimizing...
In recent years, a substantial amount of photovoltaic (PV) generations have been installed in Japanese power systems. However, the power output from the PV is random and intermittent in nature. Therefore, the PV generation poses many challenges to system operation. To evaluate impacts of the behavior of PV on power supply reliability, we have developed power supply reliability evaluation model considering...
This paper presents and analyses several approaches for transmission cost allocation in a centralized pool based electricity market environment that includes composite embedded/marginal transmission pricing mechanisms. The revenue from marginal cost based remuneration (MBR) necessitates supplementary charges; thus it is required to identify the contribution of individual generators and loads to the...
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