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Wildfires are natural or manmade disaster events that occur in forested and grassland ecosystems. Power transmission lines passing through these areas are in particular vulnerable to wildfires. The heat generated by the fire can increase the surface temperature of the overhead conductors in its vicinity. Extreme surface temperatures can lead to conductor annealing and permanent loss of tensile strength...
A cost/benefit case study was performed to evaluate the results using the Dynamic Interchange Adjustment (DINA) tool to dynamically adjust intertie flows between ISO New England and the New York (NYISO). The DINA tool is designed to provide an online probabilistic estimation of the secure range for possible intra-day and intra-hour net interchange adjustments of a BA within the next dispatch hour...
Power system interruptions have financial impacts for the utility, the customer and the community. A consistent approach to financial impact assessment for both planning and operations starts with fault data. Faults can be categorized and correlated with season and time of day in a time-element matrix. Statistical data can be modeled with Beta probability density functions. The paper shows how the...
The probabilistic load flow (PLF) problem is solved by a new approach named generalized polynomial chaos (gPC) method. This method combines the techniques of gPC expansion and Galerkin method and transforms the PLF equations into a set of deterministic equations. After the deterministic equations being solved by conventional methods, the means and variances of PLF random variables can be easily obtained...
Among renewable power sources, wind energy is the most promising technology; however, the inter-temporal uncertainty of this source makes impossible its massive integration. Forecasting of wind generation is a key factor for the economical operation of the power system. Thus, the error related to this process is typically modeled by means of a determined probability distribution to be later incorporated...
In this paper we examine potential improvements in how load and generation forecast uncertainty is captured when setting reserve levels in power systems with significant renewable generation penetration and discuss the merit of proposed new methods in this area. One important difference between methods is whether reserves are defined based on the marginal distribution of forecast errors, as calculated...
This paper presents a method of evaluating node voltages within distribution network using probabilistic load flow (PLF) analysis. It builds on the traditional deterministic load flow (DLF) approach which gives a picture of said network at one specific point in time. The probabilistic approach improves this by taking into account network uncertainties such as fluctuations in household consumption...
This paper proposes a probabilistic power flow analysis technique based on the stochastic response surface method. The probability distributions and statistics of power flow responses can be accurately and efficiently estimated by the proposed method without using series expansions such as the Gram-Charlier, Cornish-Fisher, or Edgeworth series. The stochastic continuous input variables following normal...
The electric power industry heavily relies on software tools for planning and operation. Some of these tools are widely adopted by utilities. It is foreseen that the industry will continue to use these tools until the next generation of grid analytical tools becomes available and mature. These tools, however, were usually designed to perform deterministic studies or limited probabilistic analyses...
Renewable based distributed generators are being used extensively owing to the benefits they offer for both utilities and investors. With the spread of these DGs in power systems, A precise model that follows the stochastic behavior of wind or solar is crucial for power system planning and operation. This paper presents novel probabilistic models for wind and solar based generators. These models give...
Traditional transmission planning for electric power systems involves analyzing certain system conditions for a number of contingency events based on deterministic criteria. This paper discusses the motivations for ERCOT to explore probabilistic approaches in transmission planning and presents the potential applications of probabilistic planning methods that ERCOT is currently investigating. It also...
This paper presents an assessment of the securityconstrained optimal power flow (SCOPF) solutions, under probabilistic generation and transmission contingencies. The proposed SCOPF approach schedules the optimal level of system security by balancing the security cost (i.e. out-of-merit dispatch cost) against the cost of corrective actions and expected cost of energy interruptions due to contingencies...
A key issue in the control of double fed induction generator (DFIG) wind turbine systems is to achieve an expected performance in the presence of stochastic wind speeds. To address this issue, this paper establishes a stochastic model predictive control (SMPC) scheme for the DFIG wind turbine system. The salient feature of this scheme is that it explicitly takes into account the uncertainties in wind...
A significant expansion of the power grid in Germany can be reduced, if a certain amount of the annual renewable generation is curtailed. This paper presents an approach for an optimal dynamic curtailment of renewable energy sources in meshed distribution grids. Here, the particular power feed-in is limited only if the thermal constraint of a certain line is reached. The method is specifically directed...
The increasing penetration of new variable generations in power systems necessitates the modeling of the stochastic and variable characteristics, especially the modeling of wind power forecast error. A conditional probabilistic dependent method of modeling wind power forecast error of one single wind farm and multiple wind farms is presented in this paper, providing a range of potential forecast error...
We propose an approach for robust probability density forecast of yearly peak load. The probability density forecast is robust against influential observations and error in econometric projections. By using a method akin to jackknifing, we obtain multiple instances of the yearly peak load per scenario of explanatory variables. The density forecast of the YPL is obtained using kernel density estimation...
Distributed generators (DGs) access to smart distribution network bring harmonic current injection to power system and the distribution of injected harmonic current is uncertain. Probabilistic Harmonics Power Flow (PHPF) is a tool to analyze influence of harmonic current uncertainty to the grid so that a method based on the 2m+1 point estimate method (PEM) is proposed to solve the problem. This approach...
This paper develops a long term transmission expansion optimization methodology taking the probabilistic nature of generation and demand, spatial aspects of transmission investments and different technologies into account. The developed methodology delivers a stepwise investment plan to achieve the optimal grid expansion for additional transmission capacity between different zones. In this paper,...
This paper describes a framework of incorporating smart sampling techniques in a probabilistic look-ahead contingency analysis application. The predictive probabilistic contingency analysis helps describe the impact of uncertainties caused by variable generation and load on potential violations of transmission limits. The objectives of smart sampling techniques are to represent structure and statistical...
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