Planing & Reliability
A. Ghaedi; M. Mahmoudian; R. Sedaghati
Abstract
In recent years, due to rising social welfare, the reliability has become one of most important topics of modern power network and electricity companies try to provide the electric power to the consumers with minimal interruptions. For this purpose, the electricity companies to improve the reliability ...
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In recent years, due to rising social welfare, the reliability has become one of most important topics of modern power network and electricity companies try to provide the electric power to the consumers with minimal interruptions. For this purpose, the electricity companies to improve the reliability of the power system can utilize different techniques. In this paper, new developments occurred in electricity industry including integration of large-scale renewable resources, integration of large capacity energy storage systems, integration of combined heat and electricity units into power network and demand side response plans are taken into account, and these events impact on power network reliability is assessed. Power networks are affected with integration of renewable resources. Multi-state reliability models for renewable generation plants are obtained, in the paper. Suitable number of states in the proposed reliability model is selected by calculating XB index. Besides, fuzzy c-means clustering approach is utilized for determining probability of states. For study impact of energy storage systems with large capacity on power network reliability, load model is modified. To investigate effect of combined heat and power plants on power network reliability, failure of composed elements and produced thermal power are considered in reliability model of these plants. To evaluate demand side response impact on reliability of power network, the load model is modified. The effectiveness of the proposed techniques on the reliability enhancement of power network is satisfied using numerical results performed on reliability test systems based on the suggested methods.
Planing & Reliability
A. Ghaedi; R. Sedaghati; M. Mahmoudian
Abstract
In many different nations around the world, renewable energy sources are increasingly being used to generate electricity. It is because renewable resources are sustainable, have no operating costs, and are environmentally friendly. Wind power develops quickly among renewable units, and nowadays, several ...
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In many different nations around the world, renewable energy sources are increasingly being used to generate electricity. It is because renewable resources are sustainable, have no operating costs, and are environmentally friendly. Wind power develops quickly among renewable units, and nowadays, several wind farms with large installed capacity are operating in the world. However, the erratic property of wind velocity causes generated power of wind parks to vary, which has an impact on various parts of electric network connected to wind parks and needs to be studied using new methods. In order to address reliability-based operation studies of electric network in presence of wind parks, the current research suggests a method taking into account both probabilistic and deterministic approaches for reserve scheduling. The PJM method has been modified for this reason, for incorporating wind production into the electric network. For wind farms, a several-state reliability presentation that considers hazard of assembled elements and change in produced power is developed at first stage. The appropriate amount of spinning reserve is then computed using matrix multiplication method through modified PJM methodology. Numerical simulations related to reliability test networks are provided for assessing efficacy of suggested methodology. It is concluded from numerical outcomes that the wind farms lead to the reduction of required spinning reserve. However, due to the variation of output power of wind farms arisen from variation of wind velocity, the impact of wind units in reduction of spinning reserve is less than the conventional units with the same capacity. Besides, spinning reserve calculated by well-being approach of wind farms that combines the probabilistic and deterministic indices is more accurate than the value obtained by risk indices.
Planing & Reliability
A. Bagheri; A Rabiee; S. Galavani; F. Fallahi
Abstract
Flexible AC Transmission Systems (FACTS) devices have shown satisfactory performance in alleviating the problems of electrical transmission systems. Optimal FACTS allocation problem, which includes finding optimal type and location of these devices, have been widely studied by researchers for improving ...
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Flexible AC Transmission Systems (FACTS) devices have shown satisfactory performance in alleviating the problems of electrical transmission systems. Optimal FACTS allocation problem, which includes finding optimal type and location of these devices, have been widely studied by researchers for improving variety of power system technical parameters. In this paper, a DIgSILENT-based Discrete Particle Swarm Optimization (DPSO) algorithm is employed to manage the power flow, alleviate the congestion, and improve the voltage profile in a real case study. The DPSO have been programmed in DPL environment of DIgSILENT software and applied to the power grid of Gilan Regional Electric Company (GilREC), located in north of Iran. The conducted approach is a user-friendly decision making tool for the engineers of power networks as it is executed in DIgSILENT software which is widely used in electric companies for the power system studies. The simulation results demonstrate the effectiveness of the presented method in improving technical parameters of the test system through several case studies.
Planing & Reliability
S. Abbasi; H. Abdi
Abstract
Although significant private investment is absorbed in different sectors of power systems, transmission sector is still suffering from appropriate private investment. This is because of the pricing policies of transmission services, tariffs, and especially for investment risks. Investment risks are due ...
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Although significant private investment is absorbed in different sectors of power systems, transmission sector is still suffering from appropriate private investment. This is because of the pricing policies of transmission services, tariffs, and especially for investment risks. Investment risks are due to the uncertain behaviour of power systems that discourage investors to invest in the transmission sectors. In uncertain environment of power systems, a proper method is needed to find investment attractive transmission lines with high investment return and low risk. Nowadays, wind power generation has a significant portion in total generation of most power systems. However, its uncontrollable and variable nature has turned it as a main source of uncertainty in power systems. Accordingly, the wind power generation can play a fundamental role in increasing investment risk in the transmission networks. In this paper, impact of this type of generation on investment risk and returned investment cost in transmission network is investigated. With different levels of wind power penetration, the recovered values of investment cost and risk cost in transmission network are calculated and compared. This is a simple method to find investment attractive lines in presence of uncertainties. Wherein, transmission network expansion planning (TNEP) is formulated as a multi-objective optimization problem with objectives of minimizing the investment cost, maximizing the recovered investment cost and network reliability. The point estimation method (PEM) is used to address wind speed variations at wind farms sites in the optimization problem, and the NSGA II algorithm is applied to determine the trade-off regions between the TNEP objective functions. The fuzzy satisfying method is used to decide about the final optimal plan. The proposed methodology is applied on the IEEE 24-bus RTS and simplified Iran 400 kV network.
