Power Supply Configuration Research Articles

Research on Capacity Configuration for Green Power Substitution in an Isolated Grid Containing Electrolytic Aluminum

The deployment of a green power alternative within an isolated network, powered by renewable energy sources, in the “Three North” region of China can facilitate the substitution of high-energy-consuming industrial loads with green power. However, an inadequate power supply configuration may lead to economic and reliability issues. To address this problem, effective capacity allocation within the green power alternative isolated network is proposed. The capacity allocation process starts with the design of a network structure that aligns with local conditions. Subsequently, a capacity allocation model is developed, considering economic factors, renewable energy utilization efficiency, and system reliability. The gray wolf optimizer is enhanced to establish a capacity allocation method for the green power alternative isolated network. This method is then employed to simulate and assess the performance of the network. The results indicate that the green alternative isolated grid can successfully facilitate green power substitution, satisfying the energy requirements of the loads.

Mild hybrid energy dual-slope solar stills: Design and performance

The critical increase in the lack of available freshwater worldwide owing to different anthropogenic and natural causes has led mankind to seek serious solutions, such as the use of solar stills. This study shows the design and performance of a dual-slope solar still powered by a mild hybrid power supply system. Different power supply configurations were created for the solar still, and commercial phase change materials were incorporated into the prototype. The highest freshwater production rate in the active solar still (6.76 l/m2d) was obtained when power was supplied from the portable photovoltaic plant at the beginning of the test, with an associated cost per liter of produced water of 0.2218 USD. It was shown that phase change materials increased the heat retention time and optimized the energy supply in the solar still. However, their use did not result in lower freshwater production costs.

Power Sources for Unmanned Aerial Vehicles: A State-of-the Art

Over the past few years, there has been an increasing fascination with electric unmanned aerial vehicles (UAVs) because of their capacity to undertake demanding and perilous missions while also delivering advantages in terms of flexibility, safety, and expenses. These UAVs are revolutionizing various public services, encompassing real-time surveillance, search and rescue operations, wildlife assessments, delivery services, wireless connectivity, and precise farming. To enhance their efficiency and duration, UAVs typically employ a hybrid power system. This system integrates diverse energy sources, such as fuel cells, batteries, solar cells, and supercapacitors. The selection of an appropriate hybrid power arrangement and the implementation of an effective energy management system are crucial for the successful functioning of advanced UAVs. This article specifically concentrates on UAV platforms powered by batteries, incorporating innovative technologies, like in-flight recharging via laser beams and tethering. It provides an all-encompassing and evaluative examination of the current cutting-edge power supply configurations, with the objective of identifying deficiencies, presenting perspectives, and offering recommendations for future consideration in this domain.

Optimal operation scheduling of a PV-BESS-Electrolyzer system for hydrogen production and frequency regulation

As the green hydrogen industry develops, hybrid renewable power supply configurations emerge as a solution to increasing electrolyzer load factor. In particular, solar photovoltaics (PV) paired with Battery Energy Storage Systems (BESS) will provide a suitable option for continuous power supply as their investment costs continue to decline during the next decade. An opportunity arises to use the plant’s energy resources to provide grid services without hindering hydrogen production. Motivated by this, this paper presents a chance-constrained stochastic model for the optimal operation scheduling of a PV-BESS-Electrolyzer system participating in energy and ancillary services markets. Scenarios are used to account for uncertainty in solar power availability and energy content of the frequency regulation signal, and a degradation model is included to properly consider the effect of repeated battery cycling. Computational experiments using PJM market data and a realistic time frame show the benefits of the proposed model, achieving 10.2% more profits than the deterministic benchmark problem, while maintaining low failure rates in the provision of the regulation service and a similar hydrogen production compared to an off-grid standalone operation.

Power Supply Configuration is Key! Re-Experience a Board Game About Electricity

Power Supply Configuration is Key! Re-Experience a Board Game About Electricity

Distributed power supply and energy storage configuration method in the active power distribution network

Distributed energy access and energy storage configuration are important links in the design of an active distribution network, and research on their design methods is essential to support the scientific development of an active distribution network. Therefore, on the basis of full research and demonstration, the content of the scheme design of the active distribution network and the technical principle of the overall design of the active distribution network are first determined, so that they can play the role of macro instruction in the scheme design. In addition, this paper deeply studies the capacity allocation of distributed generation and energy storage systems in the active distribution network, puts forward a general method for optimal allocation of distributed generation access and energy storage capacity, and provides design information and technical support for the active distribution network method.

Impact on the power mix and economy of Japan under a 2050 carbon-neutral scenario: Analysis using the E3ME macro-econometric model

ABSTRACT This study uses the E3ME macro-econometric model to simulate what Japan’s macroeconomy would look like and how Japan's energy composition would change if the country were to achieve carbon neutrality by 2050. The results indicate that renewable energy will account for about 90% of the power supply configuration in 2050, assuming nuclear power plants are phased out by 2040. It is also predicted that GDP will increase by 4.0%–4.5% compared with the baseline scenario and that employment will improve by 1.5%–2.0%, resulting in simultaneous achievement of carbon neutrality and economic growth. The main reasons for these projected outcomes are that increased investment in renewable generation capacity in the power sector would be accompanied by increased investment in decarbonization technologies across individual economic sectors, increased private consumption resulting from increased employment and energy efficiency savings, and an improvement in the trade balance due to a substantial reduction in fossil fuel imports. In addition, the costs of energy due to policies to reduce or eliminate carbon would rise by 45%–55% point at most above the baseline scenario even in 2050; however, this would be of little burden on the economy, considering the substantial reduction in fossil fuel energy demand. Overall, it is estimated that energy bills would be 45% lower for consumers and 11% lower for industry in 2050 compared with the baseline. Key policy insights The study shows that achieving climate neutrality does not require difficult trade-offs with economic growth. Instead, it can provide economic opportunities that arise from switching to renewables and decarbonization technologies. The rapid reduction in global renewable costs for wind and solar technologies means that the net zero transition does not have to rely on relatively more expensive nuclear power. The true costs of nuclear could be a lot higher when the costs of safety regulations are properly accounted for. Instead, investment in electricity storage should be prioritized. A well balanced decarbonization policy mix for each sector is required. Policy makers should not rely on carbon pricing instruments alone. Supporting policies such as R&D spending, renewable subsidies, regulations and energy demand reduction should also be considered.

An integrated simulation-optimization modelling approach for sustainability assessment of electricity generation system

Devising a concrete plan for power supply should conduct the best technology-capacity-time strategy while satisfying fuel, infrastructure, and trading constraints. Addressing sustainability concerning stakeholders' opinions aligned with upstream policies escalates the problem, demanding new reliable frameworks. This paper aims to develop an integrated simulation–optimization decision support system for electricity generation planning. A differential evolution algorithm simulates the future power supply configurations. A linear programming model characterizes the optimal pathways towards those futures. Multi-criteria decision-making methods are also included for determining the preference weights of sustainability indicators and ranking the scenarios. The proposed framework offers a sustainable plan for Iran by 2050. The sustainability criteria are tracked and compared with a business as usual (BAU) scheme. The results show that the broader deployment of wind turbine primarily, solar thermal subsequently, is the major source of difference in the sustainable expansion compared to BAU. Those technologies along with photovoltaics, contribute to 48% of the generation at the end of the planning horizon. However, the findings indicate that even the extensive utilization of renewable energy sources cannot guarantee sustainability improvement all through the planning period. Thus, supply-side plans should be appropriately supported by demand-side strategies.

The Experimental Evaluation of Simple Bidirectional DC/DC Converter with Snubber Compensation for Electric Vehicle Application

This research discusses the implementation of a buck-boost converter which is also known as a Bidirectional DC/DC Converter (BDC) in electric vehicles with a specific focus on electric All-Terrain Vehicles (ATV). The BDC circuit was used to integrate the main battery of the ATV (Li-Po) with the secondary battery (a 25V max./8 Farad Supercapacitor bank). This is to ensure the main battery of the ATV motor safer from unstable output load currents through the charging and discharging mechanism facilitated by BDC in order to ensure it has a longer lifetime. This discussion is more focused on the charging mechanism which occurs when the BDC is in buck mode (36V to 18 V). Meanwhile, the DC motor was used as the load inductor in this BDC circuit. It is also important to note that an interruption in the current flowing either due to a switch or other components has the ability to cause a voltage or current spike in the semiconductor switch component. Therefore, a special circuit was required to be connected to the main circuit to reduce interruption and also indicates the role of the snubber circuit in reducing the spike. This paper is more highlighted on voltage spike reduction. Moreover, LTSpice simulation was applied to verify the BDC circuit design, and the results obtained were compared with a real laboratory measurement based on the ability to change the Duty Cycle on the Vout of the BDC circuit for the charging mechanism. The determination of the desired Vout was followed by a change in the parameters of the BDC circuit such as input voltage, inductor value, switching frequency, duty cycle, and power supply configuration to determine their impact on the Vout of BDC, Spike, and MOSFET's temperature. The experiments showed that the Snubber circuit was able to compensate for voltage fluctuations in the MOSFET.

Droop control operation strategy for advanced DC converter-based electrical railway power supply systems for high-speed lines

Advanced DC converter-based electrical railway power supply systems are very promising power supply configurations for the electrification of high-speed lines. Their full controllable converter-based traction substations along with its continuous catenary, enable the reduction of power quality issues while providing an active power management. However, the power operation performance of these new configurations relies on the development of appropriate control systems. In this sense, this paper introduces a novel operation strategy based on a droop control scheme capable of adapting the power sharing between traction substations without any traffic information. The power operation performance of a simple and complex advanced DC converter-based system following the strategy proposed has been analyzed and compared with the conventional electrification approach. According to the results obtained, the operation strategy presented can adequately control the power flow in the railway grid for both scenarios.

Development of board game to encourage life cycle thinking, and trial with university students in Japan

A key aspect of encouraging people's awareness about carbon dioxide (CO 2 ) emissions associated with various products is penetration of life cycle thinking (LCT). LCT is not a simple concept and should be connected with daily behaviors; it is important to learn LCT not only in primary but also in higher education. Many previous studies suggested that active learning and games can increase the effectiveness of the learning. Against this backdrop, we developed a board game for learning LCT and investigated the effectiveness through a trial with university students. The board game covers key issues, such as power supply configuration, fuel efficiency, CO 2 emissions associated with production, operational condition and efficiency, sharing activities, one-way vs. durable products, and so on. Participants completed surveys to evaluate the LCT knowledge they acquired and the game before and after playing. The results showed that their LCT knowledge significantly increased, and was greater in the group with lower LCT knowledge before the game. The participants positively evaluated the game regarding satisfaction and extension to daily life. The positive evaluations were not directly correlated with the increase in LCT knowledge in the group with higher LCT knowledge before the game, whereas satisfaction with the game had a positive influence on the increase in LCT knowledge in the group with lower LCT knowledge before the game. Implications for improvement, such as combining the game with post-learning activities and means of showing value, were also discussed. • Board-game educational material for life cycle thinking was developed. • CO2 emissions associated with daily consumption activities were involved in it. • The game was tried and evaluated by university students. • The significant increase in LCT knowledge and positive evaluations were gained.

Ultrafine particle levels measured on board short-haul commercial passenger jet aircraft

BackgroundAirline crew members report adverse health effects during and after inhalation exposure to engine oil fumes sourced to the air supply system onboard commercial and military aircraft. Most investigations into the causal factors of their reported symptoms focus on specific chemical contaminants in the fumes. The adverse health effects reported in aircrew exposed to the aircraft air supply, bled unfiltered off the engine or Auxiliary Power Unit (APU) may be related to particulate exposures, which are widely known to effect health. While oil contaminates the aircraft air supply, some suggest that this will only occur when there is a bearing seal failure, others document that there is low level oil contamination of the air supply during normal engine operation. This brief pilot study explores whether particulate exposure may be associated with the normal engine/APU and air supply operation and to therefore increase the understanding that UFP exposures may have on crew and passengers.MethodsAn ultrafine particle counter was utilised by an experienced airline captain in the passenger cabin of four short-haul commercial passenger aircraft. All flights were under 90 min on aircraft from two different carriers ranging from 7 months to 14 years old.ResultsUFP concentrations showed maximum concentrations ranging from 31,300 to 97,800 particles/cm3 when APU was selected on as a source of air on the ground and with engine bleed air and the air conditioning packs selected on during the climb. In 2 of the 4 flights the peaks were associated with an engine oil smell. Increases in UFP particle concentrations occurred with changes in engine/APU power and air supply configuration changes.ConclusionsThis study identified increases in UFP concentrations associated with engine and APU power changes and changes in air supply configuration. These results correlated with times when engine and APU oil seals are known to be less effective, enabling oil leakage to occur. The concentrations reached in the passenger cabins exceeded those taken in other ground-based environments. UFP exposures in aircraft cabins during normal flight indicates there will be health consequences for long serving aircrew and some passengers.

Techno-economics of solar PV array-based hybrid systems for powering telecom towers

An attempt has been made to evaluate the financial feasibility of hybrid power supply option during real-time grid power unavailability (continuous and intermittent) conditions and determine the optimal hybrid power supply configurations for outdoor telecom towers in India. As grid power availability is highly dependent on locations, a review of real-time hourly grid power supply availability for telecom towers at 36 locations in different parts of India has also been presented. Ten different locations across different climatic zones were analyzed, and it was found that duration and continuity (continuous and intermittent) of power outages considerably affect the LCOE of different configurations. So it is imperative that these factors be taken into account when determining the optimal hybrid power system. Solar PV-based hybrid power supply systems were found to have lower LCOE for all power outage conditions both in continuous as well as intermittent with their values in the range of Indian rupees (INR) 6.76–INR 26.32 (US $0.095–US $0.371) per kWh for the optimal cases (1 US$ = INR 76.28 (As on April 27, 2020)). While solar PV with battery is found to be the least cost hybrid power supply options for the telecom towers located in areas with continuous grid power unavailability up to 4 h, a diesel generator also needs to be included for larger hours of continuous grid unavailability.

Research on Optimal Planning Method of Distribution Network Considering Emergency Power Supply Configuration and User Differentiated Reliability Requirements

Considering the configuration of emergency power supply in the distribution network and the differentiated reliability requirements of end users, the optimization planning model is proposed in this paper, which can harmonize economy and reliability. The model aims at the optimal total cost of the distribution network, considers the user’s differentiated reliability indicators, solves the results of the location and capacity of distributed power sources and emergency power configuration. Finally, the optimal solution is selected by the particle swarm algorithm into the program. Three scenarios are set on the IEEE-33 node system for simulation testing. The results show that this method can effectively meet the consequence.

Optimal sizing and operation for microgrid with renewable energy considering two types demand response

The integration of renewable energy sources into the power grid poses several challenges due to their variability in output power as they primarily depend on weather conditions. As a countermeasure, battery energy storage systems are introduced in order to mitigate output power fluctuations of the renewable energy sources. Moreover, demand response programs have been attracting huge attention as an effective mechanism for efficient energy management. It enables power suppliers to cope with the output uncertainty of renewable energy systems. First step, we propose an HRES design methodology that takes into account one year. In order to find the optimal power supply configuration, it is necessary to take into account the changes in load demand due to weather conditions and seasons for one year. However, the computational cost of simulating one year is huge and requires a rather long simulation time. Therefore, we propose a simplified simulation method that uses clustering to account for changes in load demand due to weather and seasonality in one year. Second, the first proposed method is used to propose a method for optimizing the HRES equipment capacity and operation schedule considering demand response. In this paper, mixed-integer linear programing is used as the optimization method. The proposed method considers two types of demand response and achieves cost reduction by controlling load demand in response to generated power fluctuations.

Effect of power quality on the design of proton exchange membrane water electrolysis systems

Water electrolyzer technologies may play a key role in the decarbonization of the fossil-fueled world economy. Electrolytic hydrogen production could bridge emission-free power generation and various energy end-use sectors to drive the energy system towards a net zero-emission level. In order to reduce the economic cost of the required energy transition, both the overall system efficiency in converting electrical energy into the chemical energy carried by hydrogen, and the material used to build electrolytic cell stacks, should be optimal. The effect of power quality on the specific energy consumption of proton exchange membrane (PEM) water electrolyzers is investigated with a semi-empirical cell model. An experimentally-defined polarization curve is applied to analyze cell-specific energy consumption as a function of time in the case of sinusoidal current ripples and ripples excited by an industrial 12-pulse thyristor bridge. The results show that the effective electrolyzer cell area should be up to five times as high as an ideal DC power supply when powered by the 12-pulse thyristor rectifier supply to match the specific energy consumption between the two power supply configurations. Therefore, the improvement of power quality is crucial for industrial PEM water electrolyzer systems. The presented approach is applicable to simulate the effect of power quality for different proton exchange membrane electolyzers.

A New Gate Drive Power Supply Configuration for Common Mode Conducted EMI Reduction in Phase-Shifted Full-Bridge Converter

This article presents a cascaded gate drive power supply configuration to reduce the common mode (CM) current in phase-shifted full-bridge (PSFB) converters. In such converters, there are at least two $dV/dt$ sources generated at different floating points associated to the parasitic capacitances of the isolated barriers of the gate drivers (power supplies, and control signal isolation units), which can increase the conducted electromagnetic interference perturbations. This article is focused on the analysis of a new gate drive power supply configuration, which reduces the CM currents that circulate in the control part of the switching cells. This improvement is achieved by modifying the impedance network of CM current pathways. Experimental results are provided to prove the effectiveness of the new gate drive power supply configuration on a PSFB converter based on SiC-MOSFET devices.

High Reliability Microgrid for a Nuclear Facility Emergency Power Supply

Abstract This paper investigates the use of a high reliability microgrid to supply emergency electrical power to a nuclear facility following loss of offsite power accident. Majority of the nuclear facilities around the world utilize diesel generators (DGs) and battery banks as emergency power to back up the grid power supply. This power supply configuration represents the concept of the microgrid system. The research work proposes reliability improvement of the emergency power supply by introducing distributed energy sources and large-scale energy storage systems. The proposed system was modeled with reliability block diagrams (RBDs) and analyzed with Monte Carlo simulation (MCS) to evaluate the system's reliability in terms of loss of power supply probability (LPSP). The analysis takes into consideration the failure probability of the components combined with the power unavailability due to the intermittent energy sources. The results show that the proposed system reduces the LPSP.

Assessing Cognitive Capacity by P3 During a Complex Manual Control Task

Abstract. Our aim was to adapt a classical P3 method to assess the free cognitive capacity during spacecraft docking training in space. Electroencephalogram (EEG) measurement in space is limited by several conditions. Based on experience with our own EEG experiments on MIR and ISS, we decided to use dry electrodes and restricted the electrode placement to the forehead. We examined whether P3 can be reliably obtained under these conditions. Subjects had to perform a manually controlled docking task simultaneously with an acoustic monitory task. The P3 component was evoked by the acoustic stimuli of the secondary task. Twenty-six subjects participated in this study, situated in a space simulation on earth. After a familiarization session, they performed the docking tasks at three difficulty levels: low, medium, and difficult. In the secondary task, subjects had to discriminate between a low (750 Hz) and a high (1,000 Hz) tone, which differed in probability of 90% and 10%, respectively. The subjects had to count the high tone and after 10 relevant tones and had to give a voice command to a power supply configuration. P3 amplitude was largest and the latency shortest during the medium difficult task. A decision matrix based on differences between the relevant and irrelevant P3 was calculated for each subject and each task. The results suggest that P3 can be recorded during a complex manual control task and can be used to assess individual free cognitive capacity.

Analysis of Techno-Economic-Environmental Suitability of an Isolated Microgrid System Located in a Remote Island of Bangladesh

Following a rise in population, load demand is increasing even in the remote areas and islands of Bangladesh. Being an island that is also far from the mainland of Bangladesh, St. Martin’s is in need of electricity. As it has ample renewable energy resources, a renewable energy-based microgrid system seems to be the ultimate solution, considering the ever-increasing price of diesel fuel. This study proposes a microgrid system and tests its technical and economic feasibility in that area. All possible configurations have been simulated to try and find the optimal system for the island, which would be eco-friendly and economical with and without considering renewable energy options. The existing power supply configuration has also been compared to the best system after analyzing and investigating all technical and economic feasibility. Sensitivity and risk analysis between different cases provide added value to this study. The results show that the current diesel-based system is not viable for the island’s people, but rather a heavy burden to them due to the high cost of per unit electricity and the net present cost. In contrast, a PV /Wind/Diesel/Battery hybrid microgrid appeared to be the most feasible system. The proposed system is found to be around 1.5 times and 28% inexpensive considering the net present cost and cost of energy, respectively, with a high (56%) share of renewable energy which reduces 23% carbon dioxide.