: به طور کلی اساس عملکرد اغلب محدودکننده های جریان خطا کاهش جریان اتصال کوتاه به وسیله واردکردن یک امپدانس بزرگ در مدار در زمان وقوع خطا است. محدودکننده های جریان خطا در مورد نوع امپدانس و چگونگی وارد شدن و خارج شدن امپدانس به سیستم با هم متفاوت هستند. دراین مقاله با در نظر گرفتن سه مکان مختلف جهت نصب محدودکننده جریان خطا در یک شبکه قدرت نمونه و همچنین تغییر نوع (سلفی یا مقاومتی) و مقدار امپدانس آن در یک بازه بزرگ، اثرات این پارامترها بر پایداری سیستم قدرت مورد بررسی و تحلیل قرار گرفته است. معیاری که برای اولین بار در این مقاله توسط نویسندگان جهت بررسی و ارزیابی پایداری گذرای سیستم قدرت مورد استفاده قرار گرفته است، روش اختلاف بین سطح شتاب دهنده و شتاب گیرنده است. اساس این روش بر مبنای معیار سطوح برابر است. موارد دیگری که در این مقاله به آن پرداخته شده است یکی ارایه روشی جهت مکان یابی و تعیین مقدار بهینه امپدانس محدودکننده جریان خطا جهت بهبود پایداری سیستم قدرت است. همچنین، اثر زمان رفع خطا بر پایداری گذرا، هنگام حضور محدودکننده جریان خطا در شبکه قدرت، مورد مطالعه قرار گرفته است. پرونده مقاله

Considering the outstanding use of renewable energy sources, most of industrial countries secure a main part of their required energy from renewable energy resources. Solar panels and wind turbines are the most important sources for the scattered production based on Renewable energies. In this study the optimized design of a solar panel, wind turbine hybrid system with superconductive magnetic energy storage (SMES), separated from network, to provide for the load demand of a military site is considered. The aim of a system optimization is specifying the number of solar panels, wind turbines, and SMESs with minimizing the cost of system's energy production. In hybrid systems, due to fluctuations in energy production of solar panels and wind turbines, accumulation systems are used in order to provide for a perpetual load. This system is also used to minimize annual costs of energy production for a system of load demand of a military site with the use of TLBO algorithm on a basis of teach-learn is being studied. پرونده مقاله

In this paper, two protective devices, recloser and cutout fuse, are placed simultaneously. Indeed, main contribution of this research is considering Distribution Generation (DG) placement in this problem. The multi objective function has been formulated based on minimizing power loss and maximizing reliability. Selection of reliability indices has been performed based on a compromise between customer satisfaction and seller. This problem is solved by Particle Swarm Optimization (PSO) algorithm and tested on the part of practical distribution system. The reliability indices are System Average Interruption Duration Index (SAIFI), Cost of Energy Not Supplied (CENS), System Average Interruption Frequency Index (SAIFI) and Momentary Average Interruption Frequency Index (MAIFI). Simulation has been performed in part of practical distribution system by introduced several scenarios and cases. پرونده مقاله

The production of electrical energy from renewable sources has become an efficient solution to deal with the lack of fossil fuels, and prevent the emission of greenhouse gases and global warming. Due to the existence of different loads in terms of feeding priority, consumers can help the microgrid control center in optimizing the use of the microgrid and supplying energy to critical loads by providing the amount of load that can be interrupted or moved at different prices. Consumer pricing can reduce operating costs, especially when market prices are high. At the same time, with this method, consumers can economize on unimportant loads. In this paper, the effect of consumer pricing on the use of microgrids is analyzed considering the types of consumers and load priorities. The demand response program is achieved with the objective function of maximizing social welfare. on the other hand, the operation is principally concerned with flattening the load curve as much as possible. The flatter the load curve, the better the capacity installed in the network , and as a result, it postpones the development of generation and transmission. In this regard, an attempt is made to operate the microgrid in the presence of demand response, so that while increasing social welfare, the load curve is flat at an acceptable level. With these goals, the problem is formulated as a multi-objective objective function based on nonlinear programming GAMS optimization software used to solve the problem, and ε constraint will be used for multi-objective optimization. پرونده مقاله

The planning and operation of microgrids have become very important challenges in the electricity industry due to the expansion of distributed generation (DG) resources and the development of demand response programs (DRPs). Microgrids generally include renewable DG resources whose generation is random. This leads to uncertainty in system planning. This study discusses microgrid operation management considering DRPs and implementation of conservation voltage reduction (CVR) in the future operation horizon. For this purpose, a stochastic operation planning model for the next day is designed, which is associated with the implementation of DRPs, CVR, and the presence of DG resources to optimize the performance of a smart microgrid to increase reliability and reduce costs. In this study, DRPs are implemented using time-of-use (TOU) and incentive-based programs. Incentive-based programs are used to deal with uncertainty in the commitment of renewable resources, and TOU programs are used to deal with the fluctuation of generation of renewable resources by establishing a relationship between uncertainty and the fluctuation of generation of these resources. Besides, CVR is applied and voltage-dependent load modeling is performed considering innovation in addition to the format of DRPs to further reduce peak loads. The uncertainty of DG resources is modeled using the information-gap decision theory (IGDT) method. This optimization is carried out on a sample microgrid using genetic algorithm (GA). According to the results, the implementation of uncertainty-based DRPs leads to cost reduction and improvement of microgrid reliability. پرونده مقاله