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Renewable energy sources, such as wind and solar, are becoming increasingly popular due to their environmentally friendly and sustainable nature. However, one major challenge associated with these systems is their intermittent nature, which makes it difficult to rely on them as a consistent source of energy. To address this challenge, researchers have developed a combined system that incorporates wind and solar resources with a battery as a storage device, which can provide a sample load pattern independent of the grid. The primary objective of this system is to determine the optimal economic combination of these resources, which can ensure a reliable and consistent supply of electricity. To achieve this objective, the Cuckoo Optimization Algorithm (COA), a metaheuristic optimization algorithm, has been used to optimize the system. The objective function has been implemented in accordance with the constraints, and the results provide insight into the optimal combination of resources. This paper provides a comprehensive analysis of the design and optimization of a wind-solar hybrid energy system with battery storage, using the COA, as well as the results of this analysis. The outcomes indicated that the optimal hybrid system model may be able to reduce system costs by 10–25%. This research's findings can be used to inform the design of sustainable and dependable renewable energy systems. [ABSTRACT FROM AUTHOR]

Fuel shortages and environmental issues have made optimal and effective management of various resources one of the most pressing issues in the current situation. There is often a separation between the heating and gas network and the power system, which is not wise when considering the economics and effectiveness of the entire system. Examining the results shows that the installed capacity has grown significantly in the last few years. This research has investigated the microgrid including wind-solar turbine, along with energy storage (battery). This energy can be used as an alternative to fossil power plants because it is readily available and renewable. This paper proposes a multi-dimensional framework for a multi carrier energy supply with a solar-wind and biogas hybrid renewable system. In this study, the amount of power exchange of sources in a microgrid independent of the distribution network and power distribution between resources and load supply have been simulated in the HOMER environment, and the output results show the optimization of power management in this network. The proposed method is completely tested and programmed in an independent microgrid during a 24-hour period. [ABSTRACT FROM AUTHOR]

Solar energy serves as one of the promising resources of renewable energy due to its abundance availability and clean nature. Climatic data such as irradiation level and temperature are essential as input variables while designing the photovoltaic-based system. This research paper presents an extensive comparative analysis of modeling approaches of photovoltaic modules using a 1-diode and 2-diode solar models studied under varying irradiation levels and temperature values. 8 different cases of solar models based on 1-diode and 2-diode models have been incorporated. Its effect on 10 performance indexes of the photovoltaic module is comprehensively investigated. Based on these parameters, these solar models are compared in detail. MATLAB/Simulink tool is applied to explore the results. Extensive results have been taken under various operating conditions. The results show that the 2-diode model exhibits excellent performance as it maximizes the efficiency by 5.41% against the 1-diode model. Also, the 2-diode model has a greater performance ratio of 41.70% than the 1-diode model. Hence, it is revealed that the performance of 2-diode models in terms of smooth output curves, increased maximum power, fill factor, and efficiency are much closer to the actual performance as compared to the 1-diode model. [ABSTRACT FROM AUTHOR]

This paper presents a broadband low-power CMOS low noise amplifier (LNA) in 130 nm technology for sub-GHz Internet of Things (IoT) applications. The proposed circuit consists of a current reuse common source amplifier (CSA) in the forward path, and a positive simple transconductance amplifier (PSTA) in the feedback path. Theoretical calculation of the input admittance shows a positive part that presents a parallel inductance. This equivalent parallel inductance in the input can cancel out the input capacitance of CSA and electrostatic discharge (ESD) pad, enhancing the frequency bandwidth in the sub-GHz frequency band. Post-layout was simulated including ESD pads and package model in 130 nm CMOS technology, LNA achieves a voltage gain of 16.5 dB in a frequency bandwidth of 50 MHz to 1.1 GHz, noise figure (NF) of less than 2.4 dB, input return loss (S11) of -11 dB, input third order intercept point (IIP3) of -11 dBm and 1 mW power consumption from a 1 V power supply, showing a good figure of merit compared to other works. The occupied core area is less than 0.002 mm². [ABSTRACT FROM AUTHOR]

Mobile Wireless Sensors Networks (MWSNs) are used in several applications presenting difficult/dangerous environment and/or requiring the movement of sensors after initial deployment. Optimizing the use of the limited energy resource in a MWSN is a key challenge for researchers to maintain longer network survival. This paper attempts to provide an energy-efficient data routing solution for large MWSNs. The aim of this work is to propose a cluster-based scheduling protocol for MWSN. The network is firstly divided into an optimal number of clusters according to sensors connectivity. Secondly, a sleep scheduling algorithm is proposed to save the energy consumption by turning off the overlapped nodes in the sensing field. This method is distributed among sensor nodes in each cluster. It is based on the perimeter coverage level of mobile sensor nodes to schedule their activities according to their weights. The weight is used to balance the energy consumption for all sensor nodes in a cluster. The proposed approach ranges from sensors deployment and their organization to their operational mode. Experimental results demonstrate that the proposed cluster-based scheduling algorithm, based on the perimeter coverage of sensors, provides higher energy efficiency and longer lifetime coverage for MWSNs as compared to other protocols. [ABSTRACT FROM AUTHOR]

Nowadays, energy supplied by the reliable manner is one of the important challenges of the distribution company in the radial distribution system. Therefore, this paper considers these challenges by the optimal DG placement to minimize power losses with considering the analysis related to the reliability and voltage profile. In this paper, exchange market algorithm (EMA) is used as a powerful tool to solve the optimization problem. In order to extract the global optimum point, EMA uses two searching operators and two absorbent operators based on the generation of random numbers. To evaluate the goals of this paper, EMA is successfully implemented on 10, 33, and 69 bus IEEE test systems. Simulation results have illustrated that power losses are reduced by the optimal DG placement and size. Finally, the analysis of obtained results has shown the system's reliability; voltage profile can be improved if the DGs are allocated optimally in the radial network. [ABSTRACT FROM AUTHOR]

In this paper, the design methodology for a high-speed 8B/10B encoding architecture has been discussed. By means of the new truth table and with the help of Pass-Transistor Logic (PTL), a new structure has been designed in CMOS technology, which shows a superior speed performance. Also, power consumption is optimized because of careful design considerations. These features, along with the simplicity of the employed circuitry are the quality of this work to be repeatedly used in high-speed communication systems. The design process has been explained in detail so that the idea can completely be understood. Moreover, the proposed structure has been demonstrated in the circuit level for better clarification. Post-layout simulation results for TSMC 0.18µm standard CMOS technology depict the correct behavior of the proposed architecture whilst the power consumption is 1.64mW from 1.8v power supply. [ABSTRACT FROM AUTHOR]

DC microgrids have gained extensive attention in the recent years. In the islanded mode of operation power sharing between sources is required. The power sharing usually is provided by employing P-V droop characteristics while the voltage local property results in power sharing error. In this paper two decentralized approaches for resolving power sharing error are studied and compared. In the first approach, sources employ proper virtual resistance. In second approach, droop characteristics are realized in the Point of Common Coupling (PCC). It is shown that by using second approach, the voltage drop is reduced and equally the voltage quality is improved. It is discussed that the reason is bypassing the voltage drop associated with the sources output resistance in the second approach. Time domain simulations of a test DC microgrid are provided to verify the results. [ABSTRACT FROM AUTHOR]

The considerable development of the electricity market subjects in recent years has provided a complex and more competitive environment for the participants. Each participant in this environment adopts a special strategy to maximize its profit or minimize its energy costs considering the significant constraints. In this paper, a short term optimal scheduling of thermal units, hydropower units, wind turbines, and pumped storage units has been proposed based on the energy market guidelines. The main objective of this research is to minimize the thermal energy production costs considering the uncertainty parameters along with the maximum utilization of clean energy production in the system. In order to evaluate the research goals, IEEE 5-bus standard test system is selected as the case study, which is equipped with both conventional and clean energy resources. In addition, probabilistic behaviors related to energy demand and wind production have been considered. Results proved the effectiveness of this model in minimizing the energy cost of thermal units. [ABSTRACT FROM AUTHOR]

This paper is concerned with a controller design method for Networked Control Systems (NCSs) with time-varying random delays. The proposed controller is an event-based controller and is able to effectively save the network bandwidth and energy resources of the system in comparison with common control schemes while guaranteeing the stability of the system. The proposed controller switches between two main triggering schemes: event-triggered control scheme and self-triggered control scheme. The stability issue in this combinatorial method is also considered. The validity of the proposed algorithm is confirmed via simulation results and the results are well compared with results from exerting event-triggered and self-triggered control individually. [ABSTRACT FROM AUTHOR]

The demand for energy is constantly increasing, which is pushing the limitations of the current grid, increasing reliance on fossil fuels, and increasing CO2 emissions. These concerns have renewed interest in discovering ways to reduce power demand on the grid through renewable energy. However, the distribution characteristics of renewable energy make it difficult to integrate effectively into the traditional power grid. As power networks increase in scale, the drawbacks of the conventional grid, such as high cost and difficult operation, will become more apparent, and it will no longer meet increasing safety, reliability, and diversity. Therefore, applying efficient methods for improving the performance of micro-grids is necessary. In this paper, the application of CRPSO algorithm based on the game theoretic formulation strategy for reducing the exchange of power between the macro station and micro-grids is proposed. The objective function of optimization involves minimizing the cost of power, loss, communication and load shedding. The advantages have caused the load of the micro-grids to be implemented as much as possible through the exchanges between the micro-grids and the cost of utilization and power supply of the loads to be minimized. Uncertainties in wind speed and solar radiation flux are also considered for the purpose of applying the random property of the distributed generation resources. The simulation results on the 33rd IEEE standard system in different scenarios indicate the desired performance of the proposed method. [ABSTRACT FROM AUTHOR]

This review paper deals with performance analysis of the published works for circuit level realization of radix-4 Booth encoder/decoders. Starting from general concept of Booth algorithm in brief form, the conventional truth table is discussed. Subsequently, the modifications which led to the circuit level implementations along with the complete and comparative analysis for the selected works, is provided. Simulations using HSPICE for TSMC 0.18μm CMOS technology and 1.8V power supply have been performed for comparing these works. Considering the required optimizations applied to the mentioned works, it can be deduced that 1.5 XOR gate level delay is reachable for radix-4 Booth encoding scheme while the output waveforms are free of any glitches. The optimized version of Booth encoder has been embedded in a 16x16 bit parallel multiplier in which, the measured latency after post layout simulations is 1992ps; which demonstrates the high potential of chosen radix-4 Booth encoding scheme for utilization in high speed parallel multipliers. [ABSTRACT FROM AUTHOR]

This research paper has aimed to provide an insight into developing a control strategy for a standalone wind energy conversion system (SWECS) intended to power a DC load. The system mainly consists of the wind turbine (WT), generator, power electronics devices, battery bank, and its charging control circuit along with pitch angle control of wind turbine. Charging of battery is attained through tip-speed ratio (TSR) MPPT logic. DC-DC converter acts as a charge controller which charges the battery in a controlled way. Pitch angle control mechanism generates appropriate pitch angle command to dampen the rotational speed of the wind turbine. It limits the turbine output power, generator speed and rectifier output voltage during high wind speed ensuring electrical and mechanical safety of the wind turbine. The three-phase self- excited induction generator (SEIG) coupled with a wind turbine is used to produce electrical power. It is connected to load via the AC-DC-DC converter to obtain regulated voltage at the load side. The efficacy of control logic developed for proposed wind energy conversion system is tested in MATLAB/Simulink platform varying wind and load profile. [ABSTRACT FROM AUTHOR]

This paper describes the development of a new generation of single phase rectifier which is used to power telecommunications equipment. A rectifier is designed in such a manner to meets with all the requirements of the telecommunications industry. A number of common single phase topologies exist that could be realized as telecommunication power supplies, however, they do not completely satisfy all the industry requirements. This paper reviews recent progress in topology, control and design aspects in single phase PFC techniques. Different switching rectifier topologies are presented for various applications. Merits and limitations of these techniques are discussed. A detailed report of an investigation in the power converter system performance is also provided. [ABSTRACT FROM AUTHOR]

In this paper two power elements for power controller in transmission line are presented: Variable Frequency Transformer (VFT) and Rotary Power Flow Controller (RPFC). In addition, here a new Optimal Power Flow (OPF) with these elements is presented. In this paper, it has been made use of the Impedance and Admittance nonsymmetrical matrix and the matrix of loss or coefficient B are calculated in a new method. It has also been indicated that the system is not optimized if optimal power flow is not considered in locating and power of flow controller in line. The proposed method was applied to a 26-bus and 6-generator system and the results were satisfactory. [ABSTRACT FROM AUTHOR]

The completely Electric Power System encompasses three parts: Generation, Transmission, and Distribution that all require maintenance to better system reliability and energy efficiency. Most generation maintenance scheduling (GMS) packages consider preventive maintenance scheduling for generating units over one or two year's time horizon to lessen the total operation costs while fulfilling system energy requirements. In advanced power systems, the inclusion of network limitations, reserve index, forced outage rates of the units, and demand for electricity have highly increased with related expansions in system size, which have led to the higher number of generators and lower reserve margins that making the generator maintenance scheduling problem more complex. This paper proposes a security constrained model for preventive generation maintenance scheduling problem. For more realistic study, system reliability indices such as transmission security, manpower constraint, and forced outage rate of the system as well as amount of system reserve are considered for the proposed maintenance scheduling problem. Impact of the load curve on GMS problem is investigated by a novel proposed penalty factor. General Algebraic Modeling System (GAMS) is utilized for solving optimization problem. An IEEE 24-bus test system is employed for simulation and show the accuracy of results. [ABSTRACT FROM AUTHOR]

Low dropout regulators are one of the most important factures of many portable devices. Thus, consider to the complexity of the circuits and increasing request for portable devices, for increasing battery life and minimizing supply noise, regulators with high efficiency, low output noise and small size is required. In this paper, two methods to improve the efficiency of LDO regulators is proposed. First method is increasing gain of the error amplifier by using cascode technique, to improve steady-state specification. Second method is using a simple subtractor circuit between error amplifier and pass transistor of LDO regulator to improve power supply rejection, slew-rate and steady-state specification. In addition, both methods are used to achieve area efficiency replacing MIM capacitors with MOS transistor. These low dropout regulators have been simulated in TSMC 0.18 μm CMOS process. Simulation results show enhancement settling time, good line and load regulation and power supply in compare with others LDO regulators. [ABSTRACT FROM AUTHOR]

In this paper the power flow control at power systems in the presence of distributed generation is analyzed. The work proposes use of Unified power flow controller (UPFC) to control the power flow at the load bus by Main supply in coordination with DG source. This work shows that using UPFC leads to the reduction of the oscillation power and voltage at the time of three phase fault in the system. The studies are performed based on the well known software, MATLAB/SIMULINK Simulation results show that the stability and effectiveness of the applied operation of DG source in coordination with the main utility can be achieved by using UPFC. [ABSTRACT FROM AUTHOR]

The recent development in renewable energy systems and the high demand for having clean and low cost energy sources encourage people to use distributed generator (DG) systems. Proper addition and placement of DG units can increase reliability and reduce the loss and production cost. In this paper using Ant Colony method, we developed an optimum placing scheme for DGs. The proposed method is tested on an IEEE 34-shinhe system. Results show that if DGs are able to generate active power, their effectiveness will increase. [ABSTRACT FROM AUTHOR]

With increase energy consumption in the world, power network development is necessary but creating a new transmission line is very costly. Therefore increasing line transmission capability is economic. We propose a method to FACTS device to the power network, in this paper and resulted in introducing decrease power network loss's and increase transmission capability with optimal choice and allocation of FACTS device by using genetic algorithm. We examine, proving this method by simulation IEEE6 bus system and using the genetic algorithm for optimal choice and allocation of FACTS device in this system. [ABSTRACT FROM AUTHOR]