International Journal of Smart Electrical Engineering
Volume:12 Issue: 2, Spring 2023

A straightforward and affordable way to improve the power factor and account for reactive power (RP) in the distribution network (DN) is to employ switched capacitor banks (SCBs). The optimal placement of these capacitors helps to reduce costs and power losses in the network. This essay offers a hybrid algorithm by combining the Harris Hawks Optimization algorithm (HHO) and the Non-dominated Sorting Genetic Algorithm Type 2 (NSGA-II) to arrange the switched capacitors (SCs) in the DN in the best possible location and scheduling. Power plant active and reactive power (ARP) generation, capacitor bank (CB) capital expenditure (CapEx)and maintenance costs, ARP losses in DN, and switching costs of SC are all factored into the proposed objective function. Furthermore, the load uncertainty in this study is modeled using the normal distribution function. Finally, the proposed optimization problem is implemented on IEEE standard 33-bus networks, and the performance of the suggested hybrid approach is compared with other commonly used multi-objective optimization algorithms. The simulation results show the higher performance of the proposed algorithm in terms of convergence speed and the objective function value.

By development of the power system in presence of the sustainable energies, the issue of grid frequency control is becoming more important. In traditional power systems, the frequency is mostly controlled by the hydroelectric power plants. This makes it troublesome in cases of dry spell or the absence of the hydro power plants. In this paper, a new method based on using wind farm equipped with PMSG, connected through HVDC link and controlled by fuzzy logic controller, is proposed to investigate the feasibility of using wind farms to improve the frequency control performance. The proposed system is tested on a four area grid and simulated in MATLAB /Simulink. It is concluded that the best performance, which is up to 26% improvement in settling time of the frequency deviation, is achieved by the proposed system in comparison to using the traditional control method and using wind farm controlled by conventional controllers.

Today, the Internet of Things is expanding due to a wide range of applications and services. The variety of devices connected to the Internet has made discussing security in these networks a challenging issue. Security includes various aspects such as botnets. Botnets are a collection of devices such as smartphones, computers, and other devices infected by a program. This program, which is a herder bot, performs many harmful operations and leads to various anomalies in the network. Identifying botnets is one of the main challenges in IoT security due to their unique complexity. In this article, we have reviewed the botnet detection methods in IoT. Since there are different botnet detection methods in IoT, we need to do detailed research on different botnet detection methods and their strengths and weaknesses. In a way that shows the evolution of these malwares. Concepts such as life cycle, command and control models, communication protocols, botnet protocols, and botnet detection methods are described in this research. In the following, the advantages and disadvantages of botnet detection methods are discussed and these methods are compared.

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.

Load changes affect the frequency of electrical networks. Frequency stabilization is very important due to the increasing penetration of renewable energy sources in power systems. Load frequency control (LFC) is used in the power system, so that the frequency of the programmed system and the power of the connection line of an interconnected area are within the specified limits. To improve the dynamic performance of the power system and control the frequency stability, LFC is used in power systems. The main task of LFC is to keep the system frequency according to the specified nominal value and to maintain the correct amount of exchange power between the control areas. In this paper, load frequency control in two-area power system is studied and simulated. Each area has a steam generating unit with a reheat steam turbine. The system equations are expressed in the state space and the system model is determined based on the transfer function. The simulation results have been obtained using Matlab software. The simulation results show the effect of Richter's parameters on the transient dynamic behavior of the system.

In recent years, hydrogen production from renewable energy has been attracting the attention of investors and politicians in the world. Although green hydrogen is still in its early stages in Iran, it has a high potential for development. Considering the importance of the above-mentioned facts and Iran's very good wind potential, the present study was the first attempt to investigate hydrogen production from wind energy in the hot and humid climate zone of Iran. The investigated stations were 5 cities of Khuzestan province and 4 large scale wind turbines were selected to be evaluated. A numerical analysis on wind data and the best fit of the Weibull function for the stations were done. Based on the coefficients k and c of the Weibull function, the amount of hydrogen produced by electrolysis was calculated. The results of the study showed that the EWT 900-52 wind turbine produced the most wind electricity, an annual 4645.85 megawatt hours of wind electricity equivalent to 68.3 tons of hydrogen, in all the investigated stations. Moreover, the suitable station was found to be Dezful, which can produce 20.36, 16.45, 11.93 and 9.44 tons of hydrogen when using wind turbines EWT 52-900, AWE 54-900, AWE 52-750 and Hewind 43-600 respectively.

The proposed structure is a closed-loop dual-band filtering antenna, in which the antenna and the resonator are combined together. The filtering antenna consists of two triangular resonators and a rectangular loop micro-strip antenna. The surface structure of a Rogers RO-4003 substrate with dielectric (εr) equal to 3.55 and insulation loss tangent (tgδ) equal to 0.0027 and a thickness of 32 mm is placed at frequencies of 3.4, 5.28 and 8 5.5 GHz, which indicates a return loss below 10 dB. This structure is suitable for Wi-Max and the fifth generation mobile communication network, and the filter antenna proposed for these applications has a suitable bandwidth and radiation pattern in its resonance frequencies. The design and analysis of the structure has been done using HFSS software. To confirm the correctness of the simulation results, a laboratory sample of the proposed filtering antenna is made and it shows the correctness of the measured values of the design and simulation

Building integrated photovoltaic (BIPV) systems have significant advantages and potential for widespread use in buildings. These systems are popular among architects and design engineers today. Despite these cases, so far no feasibility study has been performed on the supply of electricity and heat required for the building of a residential apartment in Iran using solar energy in the facade of the building. Therefore, in the present work, a 5-storey apartment in Abadan has been evaluated using TSOL Pro 5.5 and HOMER 2.81 simulation software. The solar power generation system is connected to the national electricity grid and the solar heat generation system uses a gas boiler as backup. The results showed that 55% of electricity generated, ie 6077 kWh/year is generated by the solar system connected to the grid and 7.4% of the total heat required, ie 1604 kWh/year is supplied by the solar collector system. About 1.3 tons of CO2 emissions are generated annually due to the use of the national electricity grid. Performing accurate energy-technical-environmental analysis makes the results of the present work with high accuracy correspond to reality.