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Summary form only given. In a centralized market social welfare is the desired goal for investment and optimizing this objective will result in Pareto efficiency, assuming ";adequate and costless"; transfers among market participants. However, this principle is not always true in deregulated electricity systems, where such transfers are not always feasible due to jurisdictional constraints...
Lightning storms may only last some hours, but the number of faults during these storms can represent a considerable share of the annual disturbances. In this paper, six identified lightning storms were the main interest. In general, single-phase earth faults are the most typical fault type. However, in the lightning storms we researched, short circuits represented the majority of faults. The majority...
Transmission planning in a restructured electric power system involves complex interplay between economics and engineering. To bridge the gap between economic and engineering considerations, this paper suggests a framework to clarify the interactions among various economic and engineering issues by reviewing recent theoretical and practical progress in transmission investment and transmission planning...
RTE becomes in 2005 an EDF subsidiary with enforced independent status, but RTE is practically operated and managed since 2000 as a separate and independent structure from EDF. RTE applies its own methodology to carry out investment decisions. This paper gives an overview of the transmission investments at RTE in the present market environment.
In this paper we investigate the possibility to use fractal analysis to develop an alternative way of quantifying voltage flicker. The computer experiment shows that flicker severity Pst calculated for synthetic fractal time series and voltage time series measured on an arc furnace correlates with fractal dimension of the time series. The new fractal index, "deriweight", that is able to...
A lot of different semiconductor converters are used in systems of generation and allocation: stations of back-to-back links and high voltage direct current transmissions (HVDC), active filters, different power sources, the grate variety of support equipment etc. All converters are treated by various effects from external circuits. It may be an over voltage at outcome due to the lightning on the HV...
The paper addresses the options of simplified models for estimation of power shortage in electric power systems. The models are employed in the software package for EPS reliability analysis that was developed at Energy Systems Institute. The feasibility of combining the sequential optimization procedures used earlier has been studied in terms of one criterion, i.e. determination of the minimal total...
This paper has developed a methodology for testing of substation functional circuits from the utility company. This methodology allows making all possible combinations of the functional circuits, aiming to find whether there is any fault, bad operation or project mistake in these circuits. The fundamental idea is that this set of tests, automatically made by a computer package, provide the elimination...
There is a tremendous growth in Indian power system since independence in 1947. An indicator of the growth is the Installed generating capacity which has increased from 1362 MW in December'1947 to - 1,15,000 MW by end of 2004. Indian power system has a hierarchical system. It consists of distribution Utilities i.e. State Electricity Boards (SEB)/Private companies, Central transmission utilities, Central...
The paper describes Indian power system and the reforms being undertaken to restructure it. Introduction of open access in transmission has been deliberated in detail. Various issues arising due to liberalized electricity market and the need of change in power system planning methods has been presented in the paper. Need of suitable mechanism for sharing of transmission charges in the deregulated...
Generation of electricity from wind power, as a renewable energy source, is continually attracting the attention of investors, researchers and electrical utilities. It has been predicted that the annual growth of wind power between 1998 and 2040 would be between 20% and 30%. Consequently, it is expected that wind power would supply at least 20% of the world's electricity by 2040. These figures show...
Because of the increasing cross-border power transfers, nowadays severe congestion occurs in the UCTE system. It hinders the free energy trade and endangers the network security. In this paper at first possible reinforcement measures to eliminate network congestion are analyzed. Then a method to evaluate the reinforcement measures concerning social economic welfares is introduced. A linearized network...
One of the main obstacles to the diffusion of the distributed generation (DG) is the actual distribution system structure, that was not built to allocate a large amount of generation. However, many technical and political drives are urging forward a massive penetration of DG, which will ineluctably guide to a radical transformation of the MV distribution networks. One of the changes could be the adoption...
This paper is concerned with the unit commitment of hydro generating units on an hourly basis throughout a single day. The performance criterion to be optimized includes the efficiency of hydro conversion, which depends on variations in tailrace elevation, penstock head losses and turbine-generator efficiency, as well as the cost of startup/shutdown of the hydro generating units. The paper presents...
This paper presents a method to determine the performance of relieving congestions using a thyristor controlled series capacitor (TCSC) in a transmission network by comparing locational marginal prices (LMP). The method allows to study different parameter variations - e.g. varying demand or size of the TCSC. A full AC Optimal Power Flow including transmission limits is used to model the underlying...
We present an applied mathematical model with stochastic input data for mean-risk optimization of electricity portfolios containing electricity futures as well as several components to satisfy a stochastic electricity demand: electricity spot market, two different types of supply contracts offered by a large power producer, and a combined heat and power production facility with limited capacity. Stochasticity...
The paper presents a theoretical framework to evaluate recovery resources to provide ancillary services in a liberalized power system. The available facilities are first identified and classified, then a general procedure is proposed to face both technical and economic issues involved in recovery services procurement. Restoration strategies are indeed investigated to determine the unsupplied energy...
Many models proposed in the literature to describe Low Voltage power distribution networks in consumer premises as communication media require knowledge of the electrical parameters of the cables comprising these networks. These parameters are nevertheless affected by a large number of factors which may vary greatly from case to case, making it thus very difficult to achieve an exact estimation about...
This paper proposes an enhanced adaptive Lagrangian relaxation (ELR) for transmission and ramp constrained unit commitment (TRUC) problem. ELR minimizes the total supply cost subject to the power balance, up and down 15 minute spinning reserve response time constraint, generation ramp limit constraints, on/off line minimum level constraints, minimum up and new down time constraints, generator operating...
Loss-of synchronism processes in the distribution networks with distributed energy resources are considered. They are influenced by new conditions that were not actual for the transmission system. To eliminate the loss-of-synchronism, special detection automatics is used. The application of such an automatics in low-voltage networks with distributed generation is specific. To meet the changed requirements,...
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