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Solar energy, wind energy etc. are the main sustainable energy sources used around the world. These sustainable energy sources are used in day-to-day life in various forms for numerous purposes. One of the highly used sustainable energy sources is the solar energy which with the help of photovoltaic (PV) cells can be made use for the generation of electrical power. However, these sources generate less voltage values and thus it requires a high gain converter. In this paper, a modified Luo with flyback DC to DC converter is presented that assures high voltage gain, single switch, less stress across the components and less ripple current. Furthermore, the simulations along with the hardware prototype for the presented converter is carried out and presented in this paper.

In the future, wind power is expected to become widely used due to its environmentally friendly and sustainable nature. Recent advancements in technology have also allow for the efficient use of this energy in the form of electrical power. Increased research has resulted in the development of wind turbines as energy converters. For the safety and proper operation of wind turbines, condition monitoring is imperative. According to Condition Monitoring (CM), the most common rotating equipment failure is found in wind turbines is a lack of good bearing grease. Using machine learning techniques, we've performed a CM of the wind turbine and validated our methods with fault-seeded data from a previous test. We isolate two primary characteristics from the data: kurtosis, which measures the non-Gaussianity, and then we rate it based on the kurtosis measure (NGS). In order to identify malfunctioning data, the robustness of this method is then checked using an “anomaly detection” to carry out the classification. This research shows that anomaly detection produces a better result in terms of accuracy and sensitivity as compared to SVMs.

As a typical big data representative, the information of global Cellular Signal Strength (CSS), defined as the signal power received by mobile phones, plays an important role in geographic flow analysis, because the density of such information can reflect the urbanization variables such as population, gross domestic product, built-up area, electric power consumption, and etc. Despite the importance, the real-time analysis of global CSS distribution remains a challenging problem due to the large data scale. In this paper, a Display-driven Computing (DisDC) technique is designed and applied to provide efficient large scale interactive CSS visualization, generating results by calculating the value of each pixel that directly for display that can dramatically improve system capacity in big data handling. Specifically, we present an efficient CSS measurement algorithm, which introduces spatial indexes and a corresponding query strategy; besides, an optimized parallel computing architecture is proposed to ensure the ability of real-time visualization. Experiments show that our approach obviously outperforms traditional methods and is capable of handling more than 40 million base stations in real-time. Moreover, an online demonstration is provided at https://github.com/MemoryMmy/CSSMap.

In this paper, an integrated drive converter of segmented-double-stator switched reluctance machine (SDS-SRM) with isolation and non-isolation charging capabilities for electric vehicle (EV) is presented. The proposed converter can not only reduce the number of the power switches, but also implement multiple operation modes. In non-isolation charging mode, the motor windings and existing power switches constitute a buck/boost converter to charge the battery. The appropriate rotor positions are obtained to achieve torque-free control, and the interleaved phase currents control method is introduced to reduce the charging current ripples. In isolation charging mode, the inner-stator is powered by the utility grid to drive the middle-rotor, and converts electrical energy into mechanical energy. While, the outer-stator is operated in generation mode to convert mechanical energy into electrical energy. The SDS-SRM is served as a rotating transformer to transfer the electric power to charge the battery with the galvanic isolation function. A low power proof-of-concept prototype platform is built and experiments are carried out to verify the effectiveness of the proposed integrated drive converter and the corresponding control schemes.

This paper presents a suite of analytics that are proposed to be embedded in next-generation smart sensors in electric power grids. The proposed analytics take the electrical signals as the input and unlock the full potential in signal processing and machine learning for real-time event detection and classification. Meanwhile, a robust synchrophasor estimation mechanism is housed within the proposed sensor technology that will be triggered following a detected event and guides on the adaptive selection of the best-fit (most accurate) synchrophasor estimation algorithms at all times. Embedding such analytics within the sensor and closer to where the waveforms are captured, the proposed distributed intelligence solution technology mitigates the potential risks to communication failures and latencies as well as malicious cyber threats. Our experiments demonstrate that the introduced scheme achieves improved quality of measurements with a promising event detection and classification accuracy, collectively resulting in enhanced online situational awareness in modern power grids.

The principal aim of the current research is the design and optimization of a multi-generation unit capable of generating electricity and potable water and hydrogen. The system comprises a gas turbine unit, a high-temperature solid-oxide fuel cell (SOFC), a combustion chamber, and a multi-effect desalination (MED) system. The pressurized steam and fuel enter the anode side of high-temperature SOFC and the air goes to the cathode side. Due to reactions inside the SOFC, a high amount of electricity produces, and excess H 2 enters the combustion chamber. Hot flue gases can run a gas turbine and a MED unit to generate more electrical power and desalinated water. The study illustrated the impact of current density on voltage losses and output power and output voltage of SOFC. A parametric examination is also conducted to demonstrate the influence of primary design variables on the system performance. Exergo-economic multi-criteria optimization is used to determine the optimized parameters to obtain the higher efficiency and lower cost of fuel and equipment. Calculations represented that the suggested arrangement is able to generate 53.46 kg/s desalinated water, and 54.8 MW electricity and 7.43 kg/h hydrogen energy. The system exergy efficiency under this condition is about 36.45% but the results of optimization showed that this value could rise up between 50.8% and 61.17% with the lowest system cost.

Renewable energy sources have great importance to deal with environmental detriments. To clean and sustainable future, various design renewable energy-assisted plants are of great importance. The current study examines the design and investigation of a double-flash binary geothermal energy-powered integrated system for useful products. For the purpose of producing hydrogen, power, heating, and drying, the proposed work basically consists of two steam turbines, a transcritical carbon dioxide Rankine cycle (tCO2-RC ) , a PEM electrolyzer, a domestic water heater (DHW), and a dryer. The chief target of this research study is to develop a more efficient plant as well as multigeneration productions. Additionally, detailed parametric modeling is carried out using energetically and exergetically approaches to examine this designed plant in the context of thermodynamic analysis. The variation of some parameters that influence the plant's performance, such as geothermal water temperature, flash pressure, and ambient temperature, are parametrically investigated. Subsequently, the thermodynamic simulation results show that the advised integrated plant produces 4431 kW electrical power. Also, the amount of the hydrogen generation capacity is 0.006809 kgs−1. The tCO2-RC sub-plant's energetic and exergetic performance is determined as 6.18% and 27.14%, respectively. Furthermore, the suggested integrated plant's energetic and exergetic performances are 26.20% and 37.49%. From the results, it can be finalized that the integration of various systems with the geothermal power plant is successfully possible and, in this way, there will be an increase in system performances.

Integrated power systems (IPSs) are popular in the shipbuilding industry. DC shipboard microgrids (dc-SMGs) have many advantages compared with ac ones in terms of system efficiency, operation flexibility, component size, and fault protection performance. Being in the exploring stage, dc-SMGs have several potential configurations with different system architectures and voltage levels. In a dc-SMG, functional blocks integrated include power generation modules (PGMs), propulsion system, high power loads, and pulse loads specifically in naval ships. In modern ships, the PGMs include not only generators and fuel cells (FCs) but also energy storage systems (ESSs), which cooperate with generators to improve the overall efficiency and reliability. High power electric converters are vital interfaces between the functional blocks and the dc distribution system. Rectifiers for generators take the tasks of dc bus voltage regulation and power sharing. Inverters for propulsion motors are responsible for the motor drive in different operating conditions. Bidirectional dc/dc converters for ESSs are used to provide supply-demand balance and voltage fluctuation mitigation. This paper makes a comprehensive review of power architecture, functional blocks including electrical machines and energy storage, as well as power converters in dc shipboard power systems.

Spacecraft operation in ultra-low Earth orbits (150–250 km) can provide advantages for carrying out traditional tasks. At the same time, the long-term maintenance of spacecraft in such orbits requires the delivery of a propellant supply from the Earth to compensate the aerodynamic drag. An increase in the lifetime can be achieved with air-breathing electric propulsion (ABEP) using outboard atmospheric gases as a propellant. To ensure ABEP operation, it is necessary to provide the required electric power supply and density of ionized gas. At the same time, lowering the orbit altitude or extension of solar arrays is accompanied by a rise in aerodynamic drag, the required thrust to compensate it and, therefore, the required power supply. In this paper the problem of integrated optimization of the trajectories and layout parameters of spacecraft by the criterion of the ABEP power consumption at the fixed spacecraft volume is considered. Variations in the density and composition of the atmosphere and the periods of shading of the spacecraft are taken into account. An analytical solution is obtained depending on generalized parameters that combine such characteristics as the specific power of solar arrays, total thruster efficiency and aerodynamic drag coefficient. The dependencies of the orbit characteristics enabling the long-term maintenance of spacecraft with ABEP on the generalized parameters are determined.

Probabilistic wind power forecasting is an important input in the decision-making process in future electric power grids with large penetrations of renewable generation. Traditional probabilistic wind power forecasting models are trained offline and are then used to make predictions online. However, this strategy cannot make full use of the most recent information during the prediction process. In addition, ensemble learning is recognized as an effective approach for further improving forecasting performance by combining multiple forecasting models. This paper studies an online ensemble approach for probabilistic wind power forecasting by taking full advantage of the most recent information and leveraging the strengths of multiple forecasting models. The online ensemble approach is first formulated as an online convex optimization model. On this basis, a quantile passive-aggressive regression model is proposed to solve the online convex optimization model. Case studies and comparisons with other online learning methods are conducted on an open wind power data set from Belgium. Results show that the proposed method outperforms competing methods in terms of pinball loss and Winkler score with high reliability.

This paper presents the PLC-Based system for controlling the SCR power module which is AC–DC converter proposes to linearity output voltage with trigger signal. The technique converted the trigger signal by arccosine function and analog module in the PLC. Converted signal from PLC system is fed to SCR power module instant the traditional signal. Proposed of this paper describes the PLC hardware configuration, compute/math and trigonometric functions with Studio 5000 software. In addition, the interfacing, parameters configuration, and monitoring are considered for testing. The technique with PLC-based, devices configuration and experimental results have been presented will be useful for electric power supply in the industry with more and more demand to apply the PLC system to develop the traditional industry to semi or automatic control in the industry.

Hydrogen has shown great potential in the renewable power integration and urban mobility decarbonization like the hydrogen fuel cell vehicles (HFCVs). The HFCV refueling as an essential hydrogen load is of great flexibility. Considering the HFCV demand response, this paper studies the integrated electric power and hydrogen system (IPHS) operation. First, the HFCV refueling load model is formulated with its routing on the transportation network considered. Second, the optimal IPHS operation model is developed in which the electric power operation, tube-trailer based hydrogen delivery and HFCV refueling are coordinated. Third, a Lagrangian Relaxation (LR) based method is developed to solve the proposed model efficiently, which corresponds to a price-based demand response mechanism for HFCVs. Compared with existing works on IPHS, the influence of transportation networks is delicately analyzed on both HFCV refueling and hydrogen delivery. The case studies have proven the effectiveness of the proposed method and demonstrated that the overall operation cost is decreased via the proper guidance of HFCV refueling. The HFCV demand response shows great potential in exploring the synergy of energy and transportation systems.

Wind power producers have recently gained a significant penetration in the electric power network, which might cause some challenges for the system operation due to the uncertainties in the generated power. In this way, wind power owners may offer different services, such as providing reserve capacity besides their conventional role of delivering just energy. Currently, conventional generators are the main responsible for providing some reserve in case of uncertainty in renewable generation and demand changes. Therefore, this article introduces a novel approach that allows wind power producers to participate in both energy and reserve markets alongside conventional generators. A two-stage stochastic programming model is deployed for this purpose and the proposed approach is examined on the IEEE RTS 24-bus. The simulation results demonstrate that for ensuring a higher level of reliability by the suggested scheme, both conventional generators and wind power producers will receive more revenue in both markets, although the demands should pay more.

Due to the distributed structure of electric power networks (EPNs) and district heating networks (DHNs), distributed dispatch is favorable for coordination in an integrated electricity and heat system (IEHS). However, the feasibility issue of the dispatch solution remains unresolved. Without making this clear, critical threats may be posed to system operation, and there cannot be security guarantees. In this article, we propose a distributed method for real-time IEHS dispatch where feasibility is strictly ensured in each iteration. First, a network reduction method of DHNs retaining the temperature quasi-dynamics is derived. Based on that, a novel feasibility cut (FC) generation method is devised, which strictly maintains system security during the iterative process. Finally, modified Benders decomposition with guaranteed feasibility (MBD-GF) is proposed to tackle distributed IEHS dispatch. The case studies of two IEHSs validate the effectiveness and efficiency of the proposed method.

Desiccant dehumidification systems are thermally regenerated systems that can be used either as standalone or as complementary additives for conventional cooling systems. One of their best competitive qualities is the potential to utilize low-grade heat sources for the regeneration process, thus decreasing electrical power consumption and scaling back the emissions of greenhouse gasses. However, up till now, desiccant dehumidification systems saw limited practical applications, due to their relatively high capital costs and low efficiency. To enhance the commercial competitiveness of desiccant dehumidification systems and expand their fairly tiny niche market, it was necessary to improve the system's performance and reliability and reduce their costs. A detailed discussion of the current designs configurations and the main differences between them may help future researchers to come up with novel, innovative designs, to overcome the system's drawbacks and make them actual viable alternative competitors in the dehumidification market. Consequently, this paper presents and analyzes the development of those configurations in the following three main aspects: packed bed, fluidized bed, and rotating desiccant wheel.

The need of world electricity production is growing at an increasing rate and because of its limited supply, it cannot completely be met by ordinary energy framework. The use of hybrid systems by renewable electricity sources for energy generation has also created considerations in general. There is no one source of renewables ready to continuously load electricity, and hybrid systems are thus a key solution. Renewable energy is produced by inexhaustible reserves, usually refilled on a human scale, such as sun, wind, hydro, mainstay, biomass, etc. In four core areas, renewable energy often provides energy: electricity, air and water heating/cooling, transport, and rural (stand-alone and network) energy services. In comparison with other sources, renewable power sources have reserves in large geographical regions amassed in a small number of countries. Rapid organization of renewable energy sources and energy conservation brings enormous energy stability, ecological change relief and financial benefits. Hybrid systems (PV-Biomass) are used in different regions to provide electricity to overcome discontinuity and transition in solar and wind power. This paper discusses the techno-economic feasibility analysis of solar biomass system in the Ludhiana district of Punjab.

This study proposes the integrated designs of energy systems and a re-liquefaction system for ocean-going LH2 tankers. Five prospective energy systems (Systems A to E) are suggested, using LNG as fuel, and a re-liquefaction system with a Claude cycle is developed. Their economic value, technological feasibility, and environmental impact are evaluated. The re-liquefaction systems' exergy efficiency and specific energy consumption ranges were 26.79–46.27% and 3–7.45 kWh/kg, respectively. The re-liquefaction system in System C is economically feasible up to $2/kg of H2. LCC of the integrated designs shows that System C has the lowest cost of $140 million. The shipping costs for each design are reviewed, and the lowest one is $447/ton of H2 for System C. Although System C CAPEX is the second expensive, it has the highest efficiency. Consequently, System C with the low-pressure engine, SOFC, and the re-liquefaction system is determined to be the optimal one.

A Real-time electricity market transaction is an important method that is used to realize the interactive balance of source-network-load in a new generation power system. Based on the multi-camp economic choice and the needs of national conditions, the emergence of cluster operators is inevitable. Due to stability and development of photovoltaic users, it is important to evaluate the importance of users in a photovoltaic user group. In the existing model, users are too sensitive to the electricity price, which will lead to too high electricity adjustment rate. In order to make up for the lack of importance ranking research and the high adjustment rate of electricity consumption, this paper will introduce the electric power consumption satisfaction function and propose an optimal pricing model that is based on the master-slave game. The study analyzes the nature of operators’ revenue, and presents a method to calculate the contribution value using the cooperative game theory. The TOPSIS method is proposed to evaluate the ranking of the producers and sellers in the group. The developed illustration verifies the superiority of the cluster economic operation model.

Heat powered cycles are of great interest as they enable reduced electric power consumption. Therefore, they can lower the load on electric power plants and distribution infrastructure. Many systems incorporate compressors for driving thermodynamic cycles and processes, and these compressors are usually electrically driven. In the framework of research on a sorption Joule-Thomson cryogenic cooler, a three-stage sorption compressor is designed, manufactured, and tested. The experimental results are reported and analyzed in the current manuscript. Nine experiments are reported, with one, two, and three compression stages, in which the experiments differ in the number of sorption cells at every compression stage and the operating conditions. The results of the experimental apparatus validate a numerical model and show the ability to construct and operate sorption compressors. All nine experiments operate with nitrogen, which is the required refrigerant in the cryogenics cooling system of the current research. Nitrogen is a weakly adsorbed gas, and so the reported efficiencies are relatively low, around 0.5% of the Carnot efficiency. However, the current work proves the technology's maturity and suitability for many other applications, especially where the required working fluids are more intensively adsorbed gases.

In this study, two wind-solar-based polygeneration systems namely CES-1 and CES-2 are developed, modeled, and analyzed thermodynamically. CES-1 hybridizes a heliostat based CSP system with wind turbines while CES-2 integrates heliostat-based CPVT with wind turbines. This study aims to compare the production and thermodynamics performance of two heliostat based concentrated solar power technologies when hybridized with wind turbines. The systems have been modeled to produce, freshwater, hot water, electricity, hydrogen, and cooling with different cycles/subsystems. While the overall objective of the study is to model two polygeneration systems with improved energy and exergy performances, the performances of two solar technologies are compared. The wind turbine system integrated with the comprehensive energy systems will produce 1.14 MW of electricity and it has 72.2% energy and exergy efficiency. Also, based on the same solar energy input, the performance of the heliostat integrated CPVT system (CES-2) is found to be better than that of the CSP based system (CES-1). The polygeneration thermal and exergy efficiencies for the two systems respectively are 48.08% and 31.67% for CES-1; 59.7% and 43.91% for CES-2. Also, the electric power produced by CES-2 is 280 kW higher in comparison to CES-1.

In the subsequent decades, the increasing energy will demand renewable resources and intelligent solutions for managing consumption. In this sense, Non-Intrusive Load Monitoring (NILM) techniques detail consumption information for users, allowing better electric power management and avoiding energy losses. In high-frequency NILM methods, state-of-the-art approaches, mainly based on deep learning solutions, do not provide a complete NILM architecture, including all the required steps. To overcome this gap, this work presents an integrated method for detection, feature extraction, and classification of high-frequency NILM signals for the publicly available LIT-Dataset. In terms of detection, the results were above 90% for most cases, whilst the state-of-the-art methods were below 70% for eight loads. For classification, the final accuracies were comparable with other recent works (around 97%). We also include a multi-label procedure to avoid the disaggregation stage, indicating the loads connected at a given time, increasing the recognition of multiple loads. Finally, we present results in an embedded system, a subject also underexplored in the recent literature, demonstrating the proposal’s feasibility for real-time signal analysis and practical applications involving NILM.

India ranked 5th in the world for using hydroelectric power production. As of 31 March 2020, India's total installed hydroelectric plant capability was 46,000 MW or 12.3% of its total electricity production capacity. Savonius water turbine is a useful prime mover to convert hydraulic power to electric power. It has been proven that the twisted blade of the blade has better performance than others. In the present study, the Numerical method has been used to analysis the 60° twist angles from top to bottom of the blade. The aspect ratio is taken as 1. Research is carried out for the variable load on the shaft for the same flow rate and twist angle. In the present numerical investigation, the considered angular velocity is 1 rad/s, 5 rad/s, 10 rad/s, 15 rad/s, 20 rad/s, 30 rad/s, 40 rad/s, 50 rad/s, 60 rad/s, 70 rad/s, 80 rad/s, 90 rad/s, 100 rad/s and 150 rad/s. The numerical analysis shows that the higher the load on the shaft, the lower the power generated by the turbine and vice-versa.

The deterioration of cable insulation is a widely acknowledged problem, and detection lays the foundation for maintenance and overhaul. The measurement of Tangent delta (tan δ) at very low frequency (VLF) works well on cable insulation detection, nevertheless the conventional method could only be conducted offline, where the power outage is usually required, interrupting the normal operation. To break thus a limitation, an advanced online method is proposed, and tan δ would be calculated based on the measurement of an artificially injected VLF voltage and that of the VLF leakage current through cable insulation. To coordinate with this method, an injecting source, with the comprehensive self-protection and the by-pass channel for power-frequency signals, is developed to safely inject a VLF voltage to the power system, and a monitoring system, with an accuracy better than ±0.3 μA, is established to obtain the injected voltage’s and leakage current’s waveforms, which would be used to further calculate tan δ with the cross-correlation algorithm. In addition, this method, as well as developed devices, is applied on several cables in China Electric Power Research Institute, and the measuring results keep consistent with the actual conditions, which verifies the validity.

This paper reports an experimental study on power consumption of PolyJet 3D printing. Controllable variables studied are location of samples on the build platform and volume of printed samples. The measured output is “Power Efficiency”: electrical power consumed per unit volume (cubic millimeter) of printed samples. Power Efficiency values are determined by dividing the product of consumed wattage and total print time by total volume of samples. Samples of different volumes are placed at different locations on the build platform. The results show that Power Efficiency is higher when samples are arranged along the X axis than when they are arranged along the Y axis.

Solar energy is a non-depleting source of energy where one hour of solar energy reaching on earth’s surface is enough to meet the world’s demand for a year. In present scenario people need electric power every single minute. Solar energy can be easily generated using photovoltaic panels for any type of purposes i.e., domestic or industrial. It is also very efficient and clean energy system. A lot of researches are going on solar energy to make it more efficient so that maximum energy can be drawn from sunlight. Conversion of solar energy to electrical energy includes a number of converters according to its use. One major issue related to a converter is with respect to switching losses, on state losses and sometimes complex gate circuits. Primarily from few years a lot of emphasis is given to reduce the number of switches in a converter circuit. Nine Switch Converters are a major leap in the world-changing scenario towards the converters that are being employed to the various systems, due to its various advantages which include fewer switching devices than usual, less switching losses and high-power quality. In this paper, a Photovoltaic solar array is used as a source along with a Nine-Switch converter to power a separate three-phase load. The voltage generated by the Photovoltaic solar array is regulated using a dc-dc boost converter whose output is supplied to the input of the nine-switch converter that will ultimately power the loads. The gating signals for the nine-switch converter employs the space vector modulation technique, as space vector modulation has a number of advantages when compared to other modulation techniques which includes less harmonics, higher modulation index etc. A MATLAB simulation is included to show the performance of the system.

Reducing the cost of electricity consumption by industrial enterprises is the most important area of increasing the operational efficiency of their activities. The article is devoted to the issue of reducing the cost of paying for the service component of the transport component of purchased electrical energy from industrial enterprises that have technological connection to the electrical networks of electricity producers. The article makes an empirical study of the features of the pricing of payment for the services of the transport component of purchased electrical energy for industrial enterprises connected to the electric grids of electricity producers with the identification of factors influencing the overestimation of the cost of paid electricity, and calculating such overestimations using the example of a typical schedule of electricity consumption of a machinebuilding enterprise for various regions Russia. On the basis of the developed author's indicators (tariff coefficient for electricity transportation by the level of GNP, index of tariff coefficient for electricity transportation, weighted average price for electricity transportation, index of weighted average price for electricity transportation, integral index of efficiency of GNP tariffs) study of the effectiveness of the application of tariffs for the transport of electricity for industrial enterprises connected to the electric networks of electricity producers. Based on the calculated indicators, the article groups the regions into three main groups, with the development of recommendations for managing the cost of purchasing electricity by the component of the cost of the transport component of purchased electricity in each group. As the most optimal option for reducing the cost of electricity transportation, the author proposes the introduction of demand management for electricity consumption, which will reduce the costs of industrial enterprises that pay for the transport component of purchased electricity at unfavorable tariff configurations.

Grid codes play a significant role in setting power system characteristics, such as ramp rate of different kinds of power plants. Using novel energy sources, like solar energy, for supplying electrical power demands, develops the requisite for controlling the characteristics of these sources such as their power ramp rates. While solar power is going to increase or decrease, ramp rate control is crucial. There have been suggested different strategies for power ramp rate control. Some of these strategies need batteries and some do not. Due to solar radiation uncertainties, it is necessary to use energy storage systems to control power ramp rate. On the other hand, batteries add huge costs and unreliability to the power systems. As a result, there is a trading-off among initial cost, reliability, security, and operation costs for selecting an optimal strategy. Also significance of the grid is a decisive factor. In this paper, some power ramp rate control schemes are discussed, and the advantages and disadvantages of different types of schemes have been analyzed. Also, in this literature different kinds of power ramp rate control strategies for photovoltaics have been clustered into some major sets. Besides, power ramp rate control is essential for novel schemes such as virtual synchronous machines, so emerging virtual inertia in novel power grids is another motivation to establish different methods for controlling the power ramp rate of renewable energy sources. Thus, in this paper, there is a section discussing the applications of power ramp rate control schemes.

With the growing importance of renewable energy generating resources around the world, the government is working towards expanding the share of renewable energy to 20% of total power generation considering the limitation of coal-fired and nuclear generation by 2030 in South Korea. However, the growing number of wind generating resources being connected to the electrical power system presents a challenge for transmission grid planning to increase the penetration of wind power while maintaining high levels of reliability and security of the electrical power system. In this paper, we propose a probabilistic power output model of wind generating resources for network congestion management. We use the historical data from the wind farms located on Jeju Island in South Korea to fit the Weibull distribution and implement Monte Carlo simulations. The simulation results, which represent network congestion with probabilistic values, are applied to the empirically modeled power grid of Jeju Island and a steady-state security evaluation is performed. The proposed probabilistic approach will be a key role to reduce the risk of over-investment in power transmission facilities compared to the deterministic approach to develop the generation mix scenarios with high wind power penetrations.

Wireless power transmission (WPT) using ultrasound is a promising way for wirelessly recharging implantable medical devices (IMDs). However, the transmitted power using ultrasound so far is insufficient for driving the existing IMDs. Moreover, the size of the receiving transducer is larger, which is not suitable for implantation. To increase the output power and reduce the size of the implantable receiver, this article presents a method of combining focused ultrasound with a miniaturized 1-3 piezoelectric composite receiving transducer to produce higher electrical power. An analytical fluid-structure interaction model is constructed to fully understand the operating mechanism of the receiving transducer under ultrasonic force. In our experiments, a miniaturized 1-3 piezoelectric composite receiving transducer with a diameter of 3.7 mm was used. The output power generated from the receiving transducer reached 60 mW at a distance of 150 mm. In vitro and in vivo animal experiments proved that the miniaturized transducer could successfully receive focused ultrasonic energy and convert it to electrical power. The method presented and the electrical power that we obtained can provide a valuable reference for wirelessly charging of IMDs.

The electricity demand of the fused magnesia smelting process (FMSP) is defined as the average electric power consumption over a fixed period of time, which is used to monitor the electricity cost in the FMSP. In this article, we develop a dynamic model of the electricity demand based on the closed-loop control system of the smelting current in the FMSP. The electricity demand prediction model combines an identifiable linear model with an unknown nonlinear dynamic system, which takes advantage of system identification. To predict the unknown nonlinear dynamic system, an adaptive deep learning prediction approach is proposed based on a multilayer long short-term memory. The real data in the FMSP is used to verify the effectiveness of the proposed electricity demand forecasting method.

The solar photovoltaics as an environmentally beneficial technique, have emerged as an important source of electrical power, to meet rising energy requirement and supplanting the corresponding shortages in traditional energy sources. Due to a considerable portion of the solar radiation dropping on photovoltaic cells is converted to heat; the photovoltaic power plants' efficiency is reduced. The photovoltaics panel efficiency decreases if the temperature increases, this depends on the type of solar cell used. Controlling the temperature of the solar photovoltaics has become essential to improving photovoltaic panel efficiency, especially in places where the ambient temperature is extremely high. The current paper evaluates the literature related to the application of phase change material for temperature management and electrical efficiency enhancement in photovoltaics modules. The major goal is to identify the important research topics in order to ensure that the technology performs as expected and commercially viable. Various strategies must be examined and enhanced for the site under study in order to achieve the greatest photovoltaics panel performance. According to the findings, the inorganic phase change materials offer a high capacity for cooling solar cells. Only places with high year-round solar radiation and less seasonal transitions climatic fluctuations will be cost-effective for phase change material-based photovoltaic systems. However, less thermal conductivity, in addition to low cooling are two primary issues for phase change material.

Increased electrification of aircraft power systems has been widely presented as a route toward meeting environmental and emissions targets for aircraft performance, via more-electric aircraft and future hybrid-electric aircraft concepts. In parallel, the superior mechanical performance of carbon fiber reinforced polymer (CFRP) has resulted in its increasing use for aircraft structures. The relatively low electrical conductivity of CFRP compared to traditional aluminum structures and copper conductors limits the use of structural CFRP structures as electrical elements, so separate systems are needed. This adds structural mass and volume to a system, negating some of the benefits of using CFRP. Closer integration of the composite structure and electrical power system (EPS), with an ultimate goal of achieving components with multifunctionality (combined thermal, electrical, and structural functionality), offers a route toward the light-weighting of these systems, thus supporting improvements in aircraft performance. This article presents a roadmap to achieve this multifunctionality, supported by the combination of introducing definitions for different levels of multifunctionality, associated design thresholds, and trades between the EPS and CFRP materials/structures. Existing multifunctional (MF) electrical-thermal-structural CFRP-based solutions are contextualized within this roadmap. This enables the realization of viable routes for developing MF systems for the strategic focus of future research efforts.

This paper continues discussion on financial viability and design optimisation of biomass-fired Organic Rankine Cycle (ORC) Combined Heat and Power (CHP) systems. It examines influence of such decision variables as ORC system rated electric power output, architecture and working fluid. The considered ORC system structures are simple, regenerative and regenerative cycle with split heat exchanger. Eight working fluids are considered, namely: MM, MDM, MD2M, D4, D5, toluene, ethylbenzene, and cyclohexane. The system was modelled and simulated using Ebsilon® Professional software. Sample project is assessed in terms of power generation efficiency, Primary Energy Savings (PES), and financial indicators, such as Net Present Value (NPV) and Internal Rate of Return (IRR). Results revealed considerable differences in optimal power output. The optimal value of the ORC generator power output in terms of NPV is within the range from 1000 to 2600 kW depending on the system configuration and the working fluid. In terms of IRR the optimal rated power is between 750 and 1400 kW. The highest values of nominal rated power output have been obtained for ethylbenzene. What is more, the economic indicators get higher values for hydrocarbons than for silicone oils, which are nowadays widely used in biomass fired ORC systems.

When the number of wind farms increases, the number of wind turbines placed in forested areas will also increase, this is because of the large forest areas in Sweden. When the wind turbines are placed in forested areas the fatigue loads increase drastically, so their maintenance costs increase making them less profitable. In this work clearings in forest are studied to be able to increase the electrical power generated by the wind turbines and decrease the fatigue loads to make them more profitable. The approach in this work is to use Computational Fluid Dynamics (CFD) with the Large Eddy Simulation (LES) turbulence model coupled to an aero elastic solver that solves the dynamic response of the wind turbine. Here Ryningsnas in Sweden is investigated with a homogeneous forest, the current clearing and an extended clearing. The electrical generator power was highest for the current clearing. But the fatigue loads were both higher and lower than the homogeneous forest depending on which part of the wind turbine that was investigated. The extended clearing nearly always had the lowest fatigue loads but unfortunately also the lowest electrical generator power. Further optimization of the clearings and the wind turbine locations in relation to them is needed to find the sweet spot where the fatigue loads are lower and the electrical generator power is higher.

The increase in greenhouse gas emissions from the transportation sector together with the continued depletion of fossil fuels in general has encouraged an increase in the use of energy storage systems and renewable energy sources at seaports and also on short route yachts and ferries. At present, most seaports, particularly smaller ones, are not provided with cold-ironing facilities - shore-based power facilities, which provide electric power to ships from the national grid. Because of the lack of cold-ironing facilities at most ports, auxiliary diesel engines and diesel generators on ships must be kept operating and online while at berth to supply auxiliary loads of ship. To address these requirements, one possible solution would be to provide cold-ironing facilities at all ports. However, in many circumstances, this is not cost-efficient as a port might be far from the national grid. To overcome these limitations, a seaport microgrid can be formed through the integration of multiple shipboard microgrids (SMGs) with decentralized control together with a charging infrastructure that is located on-shore. This integration of multiple SMGs and port-based charging stations is termed a ship-based seaport microgrid. Typically, power is shared among different microgrids using data communication techniques, which adds to the cost and the complexity of the overall system. This article proposes a communication-less approach based on multimode, decentralized droop control that enables power sharing among several SMGs in both charging and discharging modes based on the state of charge of battery banks - electric power is either supplied or consumed. The proposed approach would be potentially useful for future autonomous ships and also for islands where port electrification is either not technically feasible or an economically viable solution. A simulation and hardware-in-the-loop results are provided to verify the control robustness of the proposed control strategy.

Electric vehicle users need access to recharging services within the all-electrical driving range of their vehicles. However, public charging stations to be located on remote highways are in many cases far from the power grid, where a connection to the power grid may be impossible, costly, or impractical. This article formulates a stochastic mixed integer linear programming (MILP) planning model for energy storage and renewable energy systems to cover the energy demand of stand-alone charging stations for plug-in electric vehicles (PEVs) entirely using green energy generated by renewable energy sources (RESs). The proposed model accounts for the stochastic behavior of PEVs and RESs as well as the technical, economic, and operational characteristics of a variety of energy storage technologies. A customer satisfaction criterion is introduced to allow for a tradeoff between performance and investment costs. The proposed model can also be used for designing fully green PEV charging stations in urban and rural settings to capitalize on PEV environmental benefits by avoiding the use of fossil-fuel-generated electric power in their charging or to reduce the main grid load. A set of numerical studies have been performed in General Algebraic Modeling System (GAMS) environment to demonstrate the feasibility and effectiveness of the proposed model.

In the electrical power and energy (EPE) area, the traditional concept in designing the synchronization system of power converters is using the phase-locked loop (PLL) concept. An alternative way is using the frequency-locked loop (FLL) concept, which is also known as the adaptive notch filter, adaptive noise cancelation technique, gradient descent estimator, adaptive observer, D-estimation method, and transformation angle detector, among others names. Along with the increased popularity and application of FLLs in EPE systems, the misconception about this design concept is growing. To be more exact, most EPE research communities introduce FLLs as synchronization systems of different properties compared to PLLs. This article aims to explain the main reasons behind this misconception and contribute to dispelling it.

This study evaluated the effects of electrical power outages on Small and Medium Scale Enterprises (SMEs). The study was guided by two specific objectives of determining the cost of alternative sources of power supply and its impact on the profitability of businesses of selected SMEs in Elelenwo community in Obio/Akpor Local Government of Rivers State and to suggest possible ways of reducing the power outages in Elelenwo Community. The costs of power supply using private power generation and that of public power generation from Port Harcourt Electricity Distribution (PHED) were collected from selected SMEs in the study area. Findings established the fact that electrical power outages have significant negative effects on the businesses of small and medium scale enterprises (SMEs) which in turns affect their profitability and sustainability. This was established by finding the correlations of the costs of running businesses with private power generation and that of using public power generation for selected SMEs and the results yielded negative correlation coefficients. The study also suggested possible ways of reducing the power outages.

The need for energy use, especially electrical energy continues to increase from year to year. One of the sectors that consume the largest electrical energy is the household sector which consumes about 27% of the total energy consumption of all sectors. The main energy source in Indonesia at this time still comes from fossil energy, although the government has tried to develop various renewable energy sources for the future. Solar energy is one of the renewable energies that is quite potential for Indonesia considering the level of solar radiation in Indonesia is quite high throughout the year. The selection of subsidized housing as the object of research is due to the existence of clear regulations and the number which also continues to increase every year. Through the collection of physical data on the research location, such as analysis of shadows, roof structure, solar irradiation data, average electric power usage, the average solar energy requirement of the subsidized housing will be obtained. Furthermore, by calculating the economic value, it will be obtained how the description of the possibility of applying solar energy to subsidized housing will be obtained. If possible, the application of solar energy in subsidized housing can help government programs to use renewable energy and reduce the use of fossil energy

The power over fiber (PoF) scheme delivers simultaneous multiband data and feed power transmission via a double-clad fiber (DCF) for bidirectional radio over fiber (RoF) system. The 5G technology demands cell splitting resulting in an increasing number of remote antenna units (RAU). The RAU is conventionally powered by public power lines. The PoF system is the potential candidate to deliver the electrical power required to drive the RAU during the power outage due to natural calamities and disasters. The PoF system may ensure uninterrupted communication during the debacle. In the proposed scheme, the multiband data signals are generated and transmitted through the single-mode (SM) core of the DCF, whereas feed power from a high-power laser diode (HPLD) is transmitted through the inner cladding for which the core-effective area is larger than the SM core. To increase the electric power conversion efficiency, we use six customized photovoltaic converters (PVC) by introducing the back surface reflector beneath the active photovoltaic layer resulting in improved conversion efficiency of 68% at 858 nm operation wavelength. The power transmission loss can be reduced by using more PVC as it reduces the feed power leakage. As a result, the PoF system yields the power delivery of 12.33 W, sufficient to drive an RAU. The complexity of the system is reduced by using multiband signal over a single DCF and carrier reuse for uplink transmission enabling LD-free RAU. This work helps design the power delivery for the RoF system with DCF and achieve a good transmission performance with negligible power penalty.

Object and purpose of research. Electromagnetic forces in thin-walled coils of toroidal type and common type of different cross-sections (circular, rectangular, disk, spherical) are estimated and compared. Materials and methods. Methods of theoretical electric engineering are used. Main results. It is established that forces for toroidal and common coils have different character. First, there is an effect of centripetal compression, secondly, there is an effect of centripetal tensioning. Conclusions. These effects should be taken into account in the coil design, which have to withstand deformation or damage under compressive or tensioning forces.

In this age, it is undeniable that the roles of renewable resources are indispensable due to the increasing demand for electric power. With improvements in the renewable energy resources (RER) technology, integration of renewable resources for power generation is becoming more attractive and provisions are now available for consumers residing in localities with poor electricity connection to set up small renewable-based community generating units to generate electricity for their benefit. But in an interconnected electrical network, any random behaviour on the consumers side might introduce unfavourable conditions into the grid which the operators may need to rectify or mitigate. The current work is focused on investigating the feasibility of providing corrective operator-side RER integration to offset some of the negative impacts due to random consumer-side RER integration, considering an IEEE-30 bus test system. Based on the results of continuation power flow analysis, a bus with weaker voltage magnitude was considered for consumer-side RER integration, whereas for corrective operator-side RER integration, a trial and error approach was employed to search for the best location to place solar power generation unit among the load buses. Further, to study the consequences of RER integration on the small disturbance voltage stability of the system, a time domain analysis was performed using Power System Analysis Toolbox, and the system behaviour was monitored from optimally placed phasor measurement units.

A solar-powered tri-generation organic Rankine cycle (ORC) for generating electric power, producing fresh water, and providing heating power is proposed. Its performance is thermodynamically analys...

Electrical energy has become a primary need in society, including in education. This is related to the number of electrical equipment used to support teaching and learning activities. However, this is not directly proportional to the students' awareness of the importance of saving energy. From this, the authors create a management system for electric power, which aims to save electricity consumption by limiting the use of electrical loads. In this system, the method used is a decision tree; the goal is to limit and set priorities for electrical loads. When three classes are ON simultaneously, there will be a reduction in the electrical load. There is a website for monitoring and changing the automatic or manual mode in this system. The manual mode is used to control the electrical load according to the status entered on the website. While the automatic mode regulates the use of electrical loads by controlling the ON or OFF conditions using a schedule that has been made, the website also monitors current, voltage, power, energy, and usage costs. The system has been tested with automatic and manual modes for monitoring data on the website. It has data updates every 10 minutes. The system has also been tested by scheduling using a decision tree and compared with scheduling without using a decision tree. From the test results for a day, it can be concluded that the system created is able to save electricity consumption. This is reinforced by a decrease in energy use of 1,17 kWh and a cost of Rp. 1.116.

The treatment of wastewater and industrial effluents by electron beam irradiation is a promising technique, however, not very widespread in Brazilian territory. The design and construction of a mobile unit by the Nuclear and Energy Research Institute, containing an electron beam accelerator of 700 keV and 20 kW is innovative to demonstrate the effects and positive results of this technology. The aim is to transfer the mobile unit to several companies with interest in liquid waste treatment, connect to the industry electrical system and start the ionization treatment process through electron beam. The mobile unit connection to the local electrical system may be a challenge due to the great diversity of voltages and distances involved, as well as the large injections of harmonic content generated by the electron beam accelerator that can affect sensitive loads in the industrial system. In this work, an analysis of the electrical power system of the mobile unit was made, regarding the interruption capacity, selectivity protection and adequate short circuit levels, in order to assure a greater reliability in the operation. At the end, the control panel of the mobile unit, simulations and measurements were carried out at the 1.5 MeV and 37.5 kW electron beam accelerator, installed in the Radiation Technology Center, demonstrating the necessity of applying a filter to reduce the measured harmonic distortion. The analysis of the mobile unit electrical power system was made, in order to assure a greater reliability in the operation.

History instructs us that electrical power can be decarbonized in less than a dozen years with combinations of renewable and nuclear energy, but exaggerated fears of the latter have made it too cos...

Using a combined energy cycle based on conventional and/ or clean energy sources can be a suitable option to dominate the limitations in the field of energy. Meanwhile, the select of the prime power source in such processes is a challengeable issue. The selection of the prime power source from renewable sources and in addition the use of system waste heat can lead to enhance power generation. In the present work, an energy system based on conventional energy sources and clean technology is introduced and investigated. The new integrated hybrid energy cycle is composed of Miller cycle engine (MC), alkaline fuel cell (AFC), alkaline electrolyzer, Organic Rankine cycle (ORC) system and Stirling engine. MC and AFC are used as the main power sources of the cycle. On the other hand, ORC and Stirling engine for generating more electricity from the waste heat of the cycle are applied. The electrolyzer embedded in the cycle receives its electricity from the MC and provides the required inputs of the AFC. Although many studies had been done on the integration of various power generation sources with different energy cycles, attempts had not been done to establish a study on the hybrid of MC, AFC, alkaline electrolyzer, Stirling engine and ORC to produce additional electricity. Results revealed that the introduced energy system generates 3.75 kW of electric power. The portion of MC, fuel cell, ORC, and Stirling engine in electric power production is 71.2, 10.8, 9.5 and 8.5%, respectively. However, the alkaline electrolyzer consumes 2.06 kW of power and generates 48.2 g/h of H 2 fuel. It was also found that the cycle exergy destruction is 3.34 kW. In addition, the use of MC and AFC heat dissipation heat can enhance power generation.

The article describes a project to use PLC technology in railway light signs. The proposal presents a solution for the separation of supplying circuits with the use of filters. The necessity of separation is a result of long distance data transmission between sign controllers and LED railway signs using PLC modems which work on the same frequency. Problems in the selection of filter parameters are presented due to the fact that there is no specification for the characteristic of the separation filter, there are only requirements for the reliability communication system. To meet these requirements, the circuits separation efficiency must be assessed. The paper presents a quick method to evaluate separation efficiency. Structure of the network, as well as the set of devices which realize this specific kind of wired sensor network for supervising railway LED sign network and maintenance parameters are also presented in this article.

In this work, theoretical and experimental results of solid-state resonant circuits for the transmission and reception of wireless electrical energy, for applications in mobile devices are presented. Analytical expressions are found to calculate the voltage range as a function of the distance between the emitter and the load, as well as the current at the front end of an electromagnetic wave receiver. These expressions show the parameters to be varied to achieve a greater range in the transmission of wireless electrical energy. The transmitted voltage and current are measured by an electromagnetic wave receiver and compared with theoretical values, finding an excellent correspondence between the two.