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Research on Multi-Objective Optimization Model of Industrial Microgrid Considering Demand Response Technology and User Satisfaction

Junhui Li^1,*, Jinxin Zhong¹, Kailiang Wang¹, Yu Luo¹, Qian Han², Jieren Tan²
Energy Engineering, DOI:10.32604/ee.2023.021320
Abstract In the process of wind power, coal power, and energy storage equipment participating in the operation of industrial microgrids, the stable operation of wind-storage industrial microgrids is guaranteed by considering demand response technology and user satisfaction. This paper firstly sorts out the status quo of microgrid operation optimization, and determines the main requirements for user satisfaction considering three types of load characteristics, demand response technology, power consumption benefit loss, user balance power purchase price and wind power consumption evaluation indicators in the system. Secondly, the operation architecture of the windstorage industrial microgrid is designed, and the multi-objective optimization model of… More >

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ARTICLE

An Evaluation to the Performance of Evacuated Tube Solar Heaters for Arid and Hot Areas

Energy Engineering, Vol.120, No.3, pp. 587-596, 2023, DOI:10.32604/ee.2023.025407
Abstract Solar energy applications could be the best alternative to the conventional fuels for the purposes of domestic, water and space heating and some industries in the sunny, arid, and hot areas. In the present study, the performance of an evacuated tube solar heater for water heating for months of February and March was experimentally investigated. This was performed in a hot and arid area (Nasiriya City, South of Iraq). A solar heater with ten evacuated tube solar collectors with a capacity of 100 liter was used in the experiments. Each evacuated tube had a length of 1.8 m with an outside… More >

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108

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ARTICLE

Comparative Analysis of Equal and Unequal Grounding Grid Configurations by Compression Ratio and Least Square Curve Fitting Techniques

Energy Engineering, Vol.120, No.3, pp. 597-616, 2023, DOI:10.32604/ee.2023.021301
（This article belongs to this Special Issue: Evolutionary Intelligence-Based Modelling, Optimization and Control in Renewable Energy Systems)
Abstract The primary aim of the power system grounding is to safeguard the person and satisfying the performance of the power system to maintain reliable operation. With equal conductor spacing grounding grid design, the distribution of the current in the grid is not uniform. Hence, unequal grid conductor span in which grid conductors are concentrated more at the periphery is safer to practice than equal spacing. This paper presents the comparative analysis of two novel techniques that create unequal spacing among the grid conductors: the least-square curve fitting technique and the compression ratio technique with equal grid configuration for both square… More >

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67

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ARTICLE

Analysis of Temperature Rise Characteristics and Fatigue Damage Degree of ACSR Broken Strand

Energy Engineering, Vol.120, No.3, pp. 617-631, 2023, DOI:10.32604/ee.2022.024855
Abstract In this paper, the research on ACSR temperature of broken strand and fatigue damage after broken strand is carried out. Conduct modeling and Analysis on the conductor through Ansoft Maxwell software. The distribution of magnetic force lines in the cross section of the conductor after strand breaking and the temperature change law of the conductor with the number of broken strands are analyzed. A model based on electromagnetic theory is established to analyze the distribution of magnetic lines of force in the cross section of the conductor after strand breaking and the temperature variation law of the conductor with the… More >

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58

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ARTICLE

Stability Analysis and Control of DC Distribution System with Electric Vehicles

Energy Engineering, Vol.120, No.3, pp. 633-647, 2023, DOI:10.32604/ee.2022.024081
Abstract The DC distribution network system equipped with a large number of power electronic equipment exhibits weak damping characteristics and is prone to low-frequency and high-frequency unstable oscillations. The current interpretation of the oscillation mechanism has not been unified. Firstly, this paper established the complete state-space model of the distribution system consisting of a large number of electric vehicles, characteristic equation of the distribution network system is derived by establishing a state-space model, and simplified reduced-order equations describing the low-frequency oscillation and the high-frequency oscillation are obtained. Secondly, based on eigenvalue analysis, the oscillation modes and the influence of the key… More >

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57

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Research on Mixed Logic Dynamic Modeling and Finite Control Set Model Predictive Control of Multi-Inverter Parallel System

Energy Engineering, Vol.120, No.3, pp. 649-664, 2023, DOI:10.32604/ee.2023.025065
（This article belongs to this Special Issue: Evolutionary Intelligence-Based Modelling, Optimization and Control in Renewable Energy Systems)
Abstract Parallel connection of multiple inverters is an important means to solve the expansion, reserve and protection of distributed power generation, such as photovoltaics. In view of the shortcomings of traditional droop control methods such as weak anti-interference ability, low tracking accuracy of inverter output voltage and serious circulation phenomenon, a finite control set model predictive control (FCS-MPC) strategy of microgrid multi-inverter parallel system based on Mixed Logical Dynamical (MLD) modeling is proposed. Firstly, the MLD modeling method is introduced logical variables, combining discrete events and continuous events to form an overall differential equation, which makes the modeling more accurate. Then… More >

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REVIEW

Review of Optical Character Recognition for Power System Image Based on Artificial Intelligence Algorithm

Energy Engineering, Vol.120, No.3, pp. 665-679, 2023, DOI:10.32604/ee.2023.020342
（This article belongs to this Special Issue: AI Based Planning, Dispatching, and Operation of New Energy Systems)
Abstract Optical Character Recognition (OCR) refers to a technology that uses image processing technology and character recognition algorithms to identify characters on an image. This paper is a deep study on the recognition effect of OCR based on Artificial Intelligence (AI) algorithms, in which the different AI algorithms for OCR analysis are classified and reviewed. Firstly, the mechanisms and characteristics of artificial neural network-based OCR are summarized. Secondly, this paper explores machine learning-based OCR, and draws the conclusion that the algorithms available for this form of OCR are still in their infancy, with low generalization and fixed recognition errors, albeit with… More >

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59

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ARTICLE

Identification Method for Users-Transformer Relationship in Station Area Based on Local Selective Combination in Parallel Outlier Ensembles Algorithm

Energy Engineering, Vol.120, No.3, pp. 681-700, 2023, DOI:10.32604/ee.2023.024719
Abstract In the power distribution system, the missing or incorrect file of users-transformer relationship (UTR) in low-voltage station area (LVSA) will affect the lean management of the LVSA, and the operation and maintenance of the distribution network. To effectively improve the lean management of LVSA, the paper proposes an identification method for the UTR based on Local Selective Combination in Parallel Outlier Ensembles algorithm (LSCP). Firstly, the voltage data is reconstructed based on the information entropy to highlight the differences in between. Then, the LSCP algorithm combines four base outlier detection algorithms, namely Isolation Forest (I-Forest), One-Class Support Vector Machine (OC-SVM),… More >

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Optimization of Electricity Purchase and Sales Strategies of Electricity Retailers under the Condition of Limited Clean Energy Consumption

Energy Engineering, Vol.120, No.3, pp. 701-714, 2023, DOI:10.32604/ee.2022.024301
（This article belongs to this Special Issue: Key Technologies of Renewable Energy Consumption and Optimal Operation under "Dual Carbon Targets")
Abstract In the process of my country’s energy transition, the clean energy of hydropower, wind power and photovoltaic power generation has ushered in great development, but due to the randomness and volatility of its output, it has caused a certain waste of clean energy power generation resources. Regarding the purchase and sale of electricity by electricity retailers under the condition of limited clean energy consumption, this paper establishes a quantitative model of clean energy restricted electricity from the perspective of power system supply and demand balance. Then it analyzes the source-charge dual uncertain factors in the electricity retailer purchasing and selling… More >

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Traceability Technology of DC Electric Energy Metering for On-Site Inspection of Chargers

Energy Engineering, Vol.120, No.3, pp. 715-727, 2023, DOI:10.32604/ee.2022.022990
（This article belongs to this Special Issue: Advances in Modern Electric Power and Energy Systems)
Abstract The on-site inspection of high-power DC chargers results in new DC high-current measurement and DC energy traceability system requirements. This paper studies the traceability technology of electric energy value for automotive high-power DC chargers, including: (1) the traceability method of the built-in DC energy meter and shunt of the charger; (2) precision DC high current and small precision DC voltage output and measurement technology. This paper designs a 0.1 mA~600 A DC high current measurement system and proposes a 0.005 level DC power measurement traceability system. The uncertainty evaluation experiment of the DC power measurement calibration system and the high-power… More >

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ARTICLE

Studies on Performance of Distributed Vertical Axis Wind Turbine under Building Turbulence

Energy Engineering, Vol.120, No.3, pp. 729-742, 2023, DOI:10.32604/ee.2022.023398
（This article belongs to this Special Issue: Wind Energy Development and Utilization)
Abstract As a part of the new energy development trend, distributed power generation may fully utilize a variety of decentralized energy sources. Buildings close to the installation location, besides, may have a considerable impact on the wind turbines’ operation. Using a combined vertical axis wind turbine with an S-shaped lift outer blade and Φ-shaped drag inner blade, this paper investigates how a novel type of upstream wall interacts with the incident wind at various speeds, the influence region of the turbulent vortex, and performance variation. The results demonstrate that the building’s turbulence affects the wind’s horizontal and vertical direction, as well… More >

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Electric Vehicle Charging Capacity of Distribution Network Considering Conventional Load Composition

Energy Engineering, Vol.120, No.3, pp. 743-762, 2023, DOI:10.32604/ee.2023.024128
Abstract At present, the large-scale access to electric vehicles (EVs) is exerting considerable pressure on the distribution network. Hence, it is particularly important to analyze the capacity of the distribution network to accommodate EVs. To this end, we propose a method for analyzing the EV capacity of the distribution network by considering the composition of the conventional load. First, the analysis and pretreatment methods for the distribution network architecture and conventional load are proposed. Second, the charging behavior of an EV is simulated by combining the Monte Carlo method and the trip chain theory. After obtaining the temporal and spatial distribution… More >

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ARTICLE

Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir

Energy Engineering, Vol.120, No.3, pp. 763-774, 2023, DOI:10.32604/ee.2023.025893
（This article belongs to this Special Issue: Simulation of Flow and Transport Problems in Petroleum Engineering)
Abstract

Due to the characteristics of reservoir formation, the producing level of low permeability reservoir is relatively very low. It is hard to obtain high recovery through conventional development schemes. Considering the tight matrix, complex fracture system, low production level of producers, and low recovery factor of M block in Xinjiang oilfield, it is selected for on-site pilot test of nitrogen foam flooding. Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors. The pressure index, filling degree, and fluid injection profile are found to be all improved in injectors after injection of nitrogen… More >

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REVIEW

Industrial and Small-Scale Biomass Dryers: An Overview

Energy Engineering, Vol.118, No.3, pp. 435-446, 2021, DOI:10.32604/EE.2021.013491
Abstract The quality of the drying process depends mainly on the efficient use of thermal energy. Sustainable systems based on solar energy takes a leading role in the drying of agro-products because of low operating cost. However, they are limited in use during off–sun periods. Biomass dryer is one of the simplest ways of drying because of its potential to dry products regardless of time and climate conditions. The other benefit is that crop residues could be used as fuel in these systems. However, the major limitation of the dryer is unequal drying because of poor airflow distribution in the drying… More >

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Thermogravimetric and Synergy Analysis of the Co-Pyrolysis of Coconut Husk and Laminated Plastic Packaging for Biofuel Production

Energy Engineering, Vol.119, No.2, pp. 555-567, 2022, DOI:10.32604/EE.2022.018864
Abstract Unlike plastic, biomass can also be converted and produce high quality of biofuel. Co-pyrolysis of coconut husk (CH) and laminated plastic packaging (LPP) were done in this study. Synergy between these two feedstock was calculated by using thermogravimetric (TGA) and derivative thermogravimetry (DTG) analysis. Different activation energies of the reactions in the co-pyrolysis of CH and LPP were evaluated using the Coats-Redfern method. Results showed an activation energy ranging from 8 to 37 kJ/mol in the different percentage composition of the co-pyrolysis. Also, thermal degradation happens in two-stages in the copyrolysis of CH and LPP, in which CH degrades at… More >

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ARTICLE

A Novel Single Switch High Gain DC-DC Converter Topology for Renewable Energy Systems

Energy Engineering, Vol.118, No.2, pp. 199-209, 2021, DOI:10.32604/EE.2021.014079
（This article belongs to this Special Issue: Advancements in Renewable Energy Systems with AI, Big Data, BlockChain, IoT, and Machine Learning Applications)
Abstract Renewable energy with sources such as photovoltaic (PV) or fuel cells can be utilized for the generation of electrical power. But these sources generate fewer voltage values and therefore require high gain converters to match with DC bus voltage in microgrids. These high gain converters can be implemented with switched capacitors to meet the required DC bus voltage. Switched capacitors operate in a series and parallel combination during switching operation and produce high static gain, limits reverse voltage that appears across the components. A novel converter is proposed that satisfies all the features such as high voltage gain, only one… More >

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1403

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Improved Thermophysical Properties of Developed Ternary Nitrate-Based Phase Change Material Incorporated with MXene as Novel Nanocomposites

Energy Engineering, Vol.118, No.5, pp. 1253-1265, 2021, DOI:10.32604/EE.2021.016087
（This article belongs to this Special Issue: Advanced Materials and Technologies for Sustainable Energy)
Abstract In this study, nanocomposite of ternary nitrate molten salt induced with MXene is developed. LiNO₃-NaNO₃-KNO₃ with wt% of 35:12:53 and 35:10:55 are produced and doped with MXene in the wt% of 0.2, 0.5, 1.0, and 1.5. FTIR result indicates the composites had no chemical reaction occurred during the preparation. UV-VIS analysis shows the absorption enhancement with respect to the concentration of MXene. Thermogravimetric analysis (TGA) was used to measure the thermal stability of the LiNO₃-NaNO₃-KNO₃ induced with MXene. The ternary molten salts were stable at temperature range of 600–700°C. Thermal stability increases with the addition of MXene. 1.5 wt% of… More >

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859

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ARTICLE

Performance Assessment of Heat Exchangers for Process Heat Integration

Energy Engineering, Vol.118, No.2, pp. 211-224, 2021, DOI:10.32604/EE.2021.013890
Abstract Pinch Analysis is an attractive solution for reduction of thermal energy costs in thermo-chemical industries. In this approach, maximum internally recoverable heat is determined and a heat exchange network is designed to meet the recovery targets. The thermal performance of a heat exchanger over its lifetime is however a concern to industries. Thermal performance of a heat exchanger is affected by many factors which include the physical properties of the shell and tube materials, and the chemical properties of the heat transfer fluid. In this study, thermal performance of shell and tube heat exchangers designed to meet heat recovery targets… More >

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1454

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Electricity Demand Time Series Forecasting Based on Empirical Mode Decomposition and Long Short-Term Memory

Energy Engineering, Vol.118, No.6, pp. 1577-1594, 2021, DOI:10.32604/EE.2021.017795
Abstract Load forecasting is critical for a variety of applications in modern energy systems. Nonetheless, forecasting is a difficult task because electricity load profiles are tied with uncertain, non-linear, and non-stationary signals. To address these issues, long short-term memory (LSTM), a machine learning algorithm capable of learning temporal dependencies, has been extensively integrated into load forecasting in recent years. To further increase the effectiveness of using LSTM for demand forecasting, this paper proposes a hybrid prediction model that incorporates LSTM with empirical mode decomposition (EMD). EMD algorithm breaks down a load time-series data into several sub-series called intrinsic mode functions (IMFs).… More >

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Experimental Thermal Performance of Different Capillary Structures for Heat Pipes

Energy Engineering, Vol.118, No.1, pp. 1-14, 2021, DOI:10.32604/EE.2020.013572
Abstract The temperature control in electronic packaging is the key in numerous applications, to avoid overheating and hardware failure. Due to high capability of heat transfer, good temperature uniformity, and no power consumption, heat pipes can be widely used for heat dissipation of electronic components. This paper reports an experimental thermal analysis of different capillary structures for heat pipes. The wicks considered are metal screens, axial microgrooves, and sintered metal powder. The heat pipes are made of copper, a 200 mm length tube and a 9.45 mm external diameter. Working fluid used was distilled water. The devices are investigated in three… More >

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1822

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Development of Environmentally Friendly and Energy Efficient Refrigerants for Refrigeration Systems

Energy Engineering, Vol.118, No.2, pp. 411-433, 2021, DOI:10.32604/EE.2021.012860
Abstract This paper presents the improvement of eco-friendly and power consumption saving refrigerants for refrigeration systems. The novel azeotropic refrigerant mixtures of HFCs and HCs can replace refrigeration systems, and using the R134, R32, R125, and R1270 refrigerants in several compositions found using the decision tree function of the RapidMiner software (which came first in the KDnuggets annual software poll). All refrigerant results are mixed of POE, which is A1 classification refrigerant, non-flammable, and innocuous refrigerant, and using REFPROP software and CYCLE_D-HX software are under the CAN/ANSI/AHRI540 standards. The boiling point of the new refrigerant mix R-No.595 is 4.58%, lower than… More >

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A Novel Polymorphic Topology with Hybrid Control Strategy Based LLC Resonant Converter for Ultra-Wide Input Voltage Range Applications

Energy Engineering, Vol.118, No.2, pp. 341-361, 2021, DOI:10.32604/EE.2021.014229
Abstract To realize effective utilization of renewable energy sources, a novel polymorphic topology with hybrid control strategy based LLC resonant converter was analyzed and designed in this paper. By combining the merits of a full bridge LLC resonant converter, three-level half bridge LLC resonant converter, and variable frequency control mode, the converter realizes an intelligent estimation of input voltage by automatically changing its internal circuit topology. Under this control strategy, different input voltages determine different operation modes. This is achieved in full bridge LLC mode when the input voltage is low. If the input voltage rises to a certain level, it… More >

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1780

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1069

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Analysis of Electromagnetic Performance of Modulated Coaxial Magnetic Gears Used in Semi-Direct Drive Wind Turbines

Energy Engineering, Vol.118, No.2, pp. 251-264, 2021, DOI:10.32604/EE.2021.014143
（This article belongs to this Special Issue: Wind Energy Development and Utilization)
Abstract Wind turbine is a key device to realize the utilization of wind energy, and it has been highly valued by all countries. But the mechanical gear transmission of the existing wind power device has the disadvantages of high vibration and noise, high failure rate, and short service time. Magnetic field modulation electromagnetic gear transmission is a new non-contact transmission method. However, the conventional modulation magnetic gear has low torque density and torque defects with large fluctuations. In order to overcome the gear transmission problems of the existing semi-direct drive wind power generation machinery and improve the electromagnetic performance of the… More >

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