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Harmonic transient analysis of wind turbine generators (WTGs) requires reliable models to reproduce harmonic dynamics accurately and to ensure that such models perform closely to actual components.A recent harmonic modeling technique, named flexible extended harmonic domain (FEHD), is adopted in this paper as part of the proposed approach. FEHD provides reduced-order extended harmonic domain (EHD)...
The recently emerged technology IPC is aimed at solving the issues of operational control of the electric power systems. There are examples in practical use of this technology illustrating the characteristic features inherent to this family of FACTS controllers. In particular, the Plattsburgh IPC in the USA is in service operation since 1998. ABB Energy Company is the holder of a license for the development...
In the current situation, when conventional energy based on fossil fuel combustion are polluting and time-limited, there is an increasing emphasis on the exploitation of non-polluting renewable sources. At both global and European levels, particular attention is paid to the use of renewable energy sources, encouraging, through various projects, the progressive change from the use of fossil fuels to...
Extension of share of renewable energy sources in energy mix is a big challenge for our community to increase energy security and fight against global warming by cutting emissions of GHG. The paper estimate wind turbines capacity that can be integrated in actual electrical system of Moldova without its reconfiguration. The study is based on analysis of power transformer stations operating on 110kV,...
This paper presents a flexible harmonic domain (FHD) model of a three-phase photovoltaic (PV) system aimed at steady-state analysis. The proposed FHD model involves a PV array Thévenin equivalent, a DC-link capacitor, a boost converter, a three-phase inverter, an LC low-pass filter-bank, a PI-shaped distribution line, and a nonlinear load. The FHD PV model is able to include an arbitrary number of...
Protective systems require a faithful reproduction of primary current on the Current Transformer (CT) secondary side. Saturation is a common problem in a steel core CT. Current transformer (CT) saturation leads to inaccurate current measurement and, therefore, may cause malfunction of protective relays and control devices that use currents as input signals. This paper have invested an efficient practical...
Transmission expansion planning (TEP) is helping the system operator to decide the optimal solution for building new lines and in the same time to increase the reliability and safety of the existing power system. The proposed problem is a mixed-integer nonlinear programming problem (MINLP) and it is solved using stochastic programming. Stochastic programming is applied when uncertain environment occurs,...
At night, accidents are more severe and involve vulnerable people, older people with disabilities, and mothers with children. Increasing the level of illumination in the pedestrian crossing area by optimally dimensioning the associated lighting system leads to the driver being alerted to the presence of a risk area and adapting the speed of movement to avoid any danger. The projected pedestrian lighting...
The liberalization of electricity markets in Europe was a highly-debated topic in the last thirty years. Almost three decades after the start of the deregulation processes, performances obtained by the introduction of competition in the electricity markets are still difficult to be perceived by final consumers. Until now, the assumption that the deregulated electricity markets naturally generate lower...
This paper investigates the voltage fluctuations determined by industry perturbing loads in a power system, with and without a STATCOM device in operation. The monitoring campaign was carried on by simultaneously measuring the voltage fluctuations in various points of the supplying power system, for revealing each perturbing customer contribution, and the background flicker. During the measuring campaign,...
This paper deals with distribution companies (DISCOs) point of view on opportunities of optimizing investments planning and operation costs, considering possible increase and geographical displacement of high consumption buses, increasing the consumption at different time instants in other buses, by optimally installing and sizing distributed energy resources. The optimization problem is sizing and...
The present paper deals with an electricity market software package developed for educational purposes. The electricity market package presents mainly the day-ahead market and methods for the electricity consumption forecast. The simulator, designated for students, report all the steps required for generators and buyers to participate to the day-ahead market, determining the market clearing price,...
This paper compares three possibilities for determining the flicker level generated by industrial customer with arc furnaces: by calculating the electromagnetic perturbations, by experimental measurements, and by simulation using specialized software. The influence of the fault level on the propagation of perturbation in the power system represents a challenging issue studied within the existing context...
The paper presents the impact of connecting Renewable sources to the Smart Grid with regard to improving Power Quality aspects. The impact of integrating renewable sources on Power Quality indices in the grid wes analyzed and the measures for avoiding the negative impact are included in the paper. Challenges coming from the integration of renewables – variability and uncertainty and the correlation...
This paper presents results of power quality monitoring collected from transmission system operator (TSO) and several distribution system operators (DSOs) from Romania. The power quality monitoring system is realized in accordance with actual technologies, economic criteria, performance standards and technical codes issued by the Romanian Energy Regulation Authority (ANRE). The implementation of power...
The existing trend of consumption increase and population growth, combined with reduction of primary energy resources, determined adoption of energy efficiency increase measures to better cope with the existing necessities. The main characteristics of smart cities are starting to be defined such that to be applied to various cities with different population, sizes and level of technology development...
To accommodate the intermittent renewable energy sources in existing power systems, the expansion of networks, storage integration, back-up capacities and efforts for a flexible consumption are required, otherwise grid can be overloaded. The transmission expansion planning (TEP) has the purpose to ensure two important objectives: economic trade and engineering reliability. TEP can increase the competitiveness...
In addition to the lowering of consumption, the smart grid of the future will be able to reduce the peak levels of demand through a more efficient allocation of consumption over the day. For this purpose, end users need to rely on energy monitoring and control systems that provide detailed information about how and when to use and indicate how actively to contribute to the reduction of peak demand...
The present paper deals with the results of one month monitoring campaign of operating regimes of an existing ac arc furnace facility and its impact on power quality. Synchronized measurements were carried on in different points of the supply system of the arc furnace facility. Different supply schemes of the electric arc furnace facility were proposed and implemented, monitoring the power quality...
In the last years, the conducted studies for connecting renewable energy sources with small installed capacity to the electrical grid highlighted the importance of the grid characteristics and on the technical conditions required for the equipments. The operation of wind farms in the electrical system is restricted by its capacity to absorb the produced power and to ensure the required adequacy. The...
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