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DC offset has significant effect on extracting fundamental frequency components. It directly impacts the accuracy of the fundamental frequency component based protective relaying algorithms. This paper proposes a novel method for estimating the fundamental phasor while eliminating the DC offset using improved recursive wavelet transform. The proposed approach converges to the actual value in less...
Power supply reliability is one of the main criteria in estimation of power system networks. The decisions on radical changes in branch of electric power control and trade are still caused by essential monopolization, then reasoned with politicians, public, economic and technical factors and not less with international influence followed by ascendance to international alliances and wherewith connection...
This paper presents a steady state performance analysis carried out to evaluate the operation and behavior of a two VSC-based level-full scale frequency converter working as a HVDC link. The digital model has been implemented and evaluated using PSCAD/EMTDCcopy. The emphasis of this work has been put on evaluating the transferred active and reactive power from the rectifying station to the inverting...
The Power System Simulation package PSSregNETOMAC (Network Torsion Machine Control) offers a wide range of modern methods of analyzing and synthesizing electric power systems. In order to design individual elements of transmission systems or to perform stability calculations on large systems, it is possible to simulate electrical networks in the time domain and also, with the aid of Eigenvalue calculations,...
This paper deals with the influence of network topological changes on the resistive losses for a significant period. It is based on a previous work where the goal was to reduce power losses on a peak load situation. The second part of the work, presented here, attempts to reduce the energy losses of transmission network by implementing a cyclic search of topology changes and phase shifting adjustments...
Wind energy is produced at random times, whereas the energy consumption pattern shows distinct demand peaks during day-time and low levels during the night. The use of a refrigerated warehouse as a giant battery for wind energy is a new possibility that is being studied for wind energy integration as well as a way to store electricity produced during night-time by wind turbines. The controller for...
This paper evaluates using of Demand Response (DR) programs for congestion management as well as reducing the risk of supplying the loads. For this purpose, a coordination process between GENCOs and the ISO is considered. In the proposed approach, the coordination is modeled as a two-stage process. At first, GENCOs apply a priced-based unit commitment and submit their bids to the ISO for maximizing...
This paper presents an optimization-based method to model the mid-term operation of a hydrothermal power system in a competitive market. Two market structures are examined: perfect competition and oligopoly comprising a dominant firm with a competitive fringe. In the latter, the dominant firm bidding strategy is determined by solving a profit maximization problem; forward contracts are also modeled...
Traditionally, the objective in undertaking a generation expansion planning (GEP) process has been to minimize the expected sum of yearly discounted costs (incorporate i.e., construction costs, operating costs, salvage value, etc.). Now, the objective is to apply GEP to today's competitive electricity markets in order to maximize the profits of individual GENCOs (i.e., the revenues based on market...
The notion of modeling is essential to modern techniques of control and operation process. Developing a control process in fact means developing a model that allows us to predict the action and reduce the amount of feedback required. Recently the fuzzy modeling has become driving force that today is reflected in many different software and hardware products. The paper presents improvements of the...
Many engineering areas are benefiting from the abundance of powerful computing capabilities, which allows for the application of computationally intensive techniques, such as computational intelligence. Such techniques are frequently universal and do not require excessive tailoring for the specific problem. That makes it attractive for wide use, but is however, sometimes, unjustified. This paper discusses...
This paper describes the design of a compensating algorithm for an iron-cored measurement current transformer (CT) that removes the effects of the hysteresis characteristics of the iron-core. The exciting current resulting from the hysteresis characteristics of the core causes an error between the primary current and the secondary current of the CT. The proposed algorithm decomposes the exciting current...
This paper analyses some issues related to the transmission cost allocation for grids with open access. Allocation methods based on electricity tracking are presented and compared with methods based on sensitivities as well as with the postage stamp rate. The main purpose is to appraise in a critical manner the practicality of these methods and their capacity to send efficient economical signals....
To improve operational flexibility, we proposed the loop or mesh structure for distribution systems using looping device called loop power flow controller (LPC) at the opened switch which can connect the adjoining feeder as an active distribution system. LPC is able to optimally control distribution systems in the points of reducing voltage rise, voltage fluctuation and loss minimum power flow control,...
A VFT park model suitable for stability analyses of asynchronous links is presented in this work. This model allows the simulation of multi-unit VFTs operated in parallel in order to increase the power transfer between two electric power systems. The backbone of the VFT model relies on a reduced order model of a wound-rotor induction machine. The VFT control system includes power and speed regulators...
Differences in energy prices between liberalized market regions are one of the elements to be considered during power system planning. The regional prices of electricity depend on the regional portfolio of generation units. In the paper one focus of the power system planning, namely the planning of interconnections, i.e. transmission network capacities for energy exchanges between market regions has...
In this paper, the short term transmission network expansion planning (STTNEP) is solved through a specialized genetic algorithm (SGA). A complete AC model of the transmission network is used, which permits the formulation of an integrated power system transmission network expansion planning problem (real and reactive power planning). The characteristics of the proposed SGA to solve the STTNEP problem...
This paper explains the way in which the current U.S. electric system contains insufficient incentives for long-term investments in transmission. Moreover, it highlights some key issues that should be considered to improve these investment incentives. The paper shows that, under the current U.S. transmission system, independent merchant investors, transmission rights' holders, and generation firms...
A fundamental phase in the electrical systems planning is the temporal and spatial load forecasting. By changes in the structures of electricity markets and implementing policies for energy optimization, it is necessary to consider new variables that detail of better form the behavior's forecasting and expansion of the electrical consumption to medium and long time. This work proposes a global load...
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