Haichao Wang¹, Yingying Fan^2,3,*, Weigao Meng⁴, Qiaoran Yang⁵

Energy Engineering, Vol.119, No.3, pp. 1075-1101, 2022, DOI:10.32604/ee.2022.019584

Abstract Sustainability evaluation of regional microgrid interconnection system is conducive to a profound and comprehensive understanding of the impact of interconnection system projects. In order to realize the comprehensive and scientific intelligent evaluation of the system, this paper proposes an evaluation model based on combination entropy weight rank order-technique for order preference by similarity to an ideal solution (TOPSIS) and Niche Immune Lion Algorithm-Extreme Learning Machine with Kernel (NILA-KELM). Firstly, the sustainability evaluation indicator system of the regional microgrid interconnection system is constructed from four aspects of economic, environmental, social, and technical characteristics, and the evaluation indicators are explained. Then, the… More >

Chen Wang¹, Cicilia Kemunto Mesa^2,*, Samuel Bimenyimana^1,3, Nathan Bogonko², George Adwek⁴, Yiyi Mo¹, Godwin Norense Osarumwense Asemota^5,6, Changfu Yuan⁷, Yaowen Chen⁷, Changtai Li⁸, Etienne Ntagwirumugara⁹, Aphrodis Nduwamungu⁵

Energy Engineering, Vol.119, No.3, pp. 863-881, 2022, DOI:10.32604/ee.2022.019248

Abstract Offsetting particulate matter emissions has become a critical global aim as there are concerted efforts to deal with environmental and energy poverty challenges. This study consists of investigations of computing emissions of particulate matter from biomass fuels in various atmospheres and temperatures. The laboratory setup included a fixed bed electric reactor and a particulate matter (PM) measuring machine interfaced with the flue gas from the fixed bed reactor combustion chamber. The experiments were conducted at seven different temperatures (600°C–1200°C) and six incremental oxygen concentrations (21%–100%). Five biomass types were studied; A-cornstalk, B-wood, C-wheat straw, D-Rice husk, E-Peanut shell, each pulverized… More > Graphic Abstract

Chandrakant Dondariya^*, D. K. Sakravdia

Energy Engineering, Vol.119, No.3, pp. 947-963, 2022, DOI:10.32604/ee.2022.019118

Abstract This paper presents a newly developed proximity indicator for voltage stability assessment which can be used to predict critical real system load and voltages at various load buses at critical loading point. The proximity indicator varies almost parabolic with total real load demand and reaches orthogonally to real load axis. This relation has been utilized to predict critical loading point. It has been shown that two operating points are needed for estimating critical point and proper selection of operating points and variation of proximity indicator near collapse point highly affect the accuracy of estimation. Simulation is based on load flow… More >

Farzad Jaliliantabar^1,2,*, Rizalman Mamat³, Sudhakar Kumarasamy^2,4,5

Energy Engineering, Vol.119, No.3, pp. 847-861, 2022, DOI:10.32604/ee.2022.019051

Abstract Thermal characteristics of phase change material (PCM) are important in design and utilization of thermal energy storage or other applications. PCMs have great latent heat but suffer from low thermal conductivity. Then, in recent years, nano particles have been added to PCM to improve their thermophysical properties such as thermal conductivity. Effect of this nano particles on thermophysical properties of PCM has been a question and many experimental and numerical studies have been done to investigate them. Artificial intelligence-based approach can be a good candidate to predict thermophysical properties of nano enhance PCM (NEPCM). Then, in this study an artificial… More >

Lei Ren, Lei Zhang^*

Energy Engineering, Vol.119, No.3, pp. 1179-1196, 2022, DOI:10.32604/ee.2022.018902

Abstract Due to the components at twice the fundamental frequency of output voltage in the instantaneous output power of a two-stage single-phase inverter (TSI), the second harmonic current (SHC) is generated in the front-end dc-dc converter (FDC). To reduce the SHC, optimizing the control strategy of the FDC is an effective and costless approach. From the view of visual impedance, this paper conducts an intensive study on the SHC reduction strategies. Origin of the SHC is illustrated first. Then, the equivalent circuit models of the FDC under different control strategies are proposed to analyse the SHC propagation characteristic. The derived model… More >

Indra Mamad Gandidi^1,2,*, Edy Suryadi³, Efri Mardawati³, Dwi Rustam Kendarto³, Nugroho Agung Pambudi^4,*

Energy Engineering, Vol.119, No.3, pp. 1169-1178, 2022, DOI:10.32604/ee.2022.018821

Abstract Pyrolysis is one of the thermal cracking methods to convert hydrocarbon to liquid fuel. The quantity and quality of the process are dependent on several condition including temperature, reaction time, catalyst, and the type of reactor. Meanwhile, a gasoline fraction was maximum product to be considered in the pyrolisis process. Therefore, this study aims to increase the gasoline fraction in liquid fuel using stepwise pyrolysis with a long bed catalytic reactor downstream (LBCR). The LBCR downstream was equipped with the top and bottom outlet and the fed source was mixed municipal solid waste (MMSW). The activated natural dolomite at 500°C… More >

Kehinde Adeyeye^1,*, Nelson Ijumba^1,2, Jonathan Colton^1,3

Energy Engineering, Vol.119, No.3, pp. 997-1015, 2022, DOI:10.32604/ee.2022.018677

Abstract This paper posits that a low-speed wind turbine design is suitable for harnessing wind energy in Africa. Conventional wind turbines consisting of propeller designs are commonly used across the world. A major hurdle to utilizing wind energy in Africa is that conventional commercial wind turbines are designed to operate at wind speeds greater than those prevalent in most of the continent, especially in sub-Sahara Africa (SSA). They are heavy and expensive to purchase, install, and maintain. As a result, only a few countries in Africa have been able to include wind energy in their energy mix. In this paper, the… More >

Bin Zhang, Boqiang Wei^*

Energy Engineering, Vol.119, No.3, pp. 1197-1218, 2022, DOI:10.32604/ee.2022.018411

Abstract The non-cascade permanent magnet synchronous motor control system has the advantages of simple structure and less adjustable parameters, but the non-cascade structure needs to solve the problem of over-current protection. In this paper, a current constrained control method is used to limit the starting current to a safe range. At the same time, to ensure the robustness and rapidity of the system, a super twist current constraint controller (CCSTA) is generated by combining super twist algorithm (STA) with current constraint control; Considering the diversity of internal and external disturbances, a functional disturbance observer (FDOB) is proposed to compensate the matched… More >

Tao Guo, Gang Tian, Zhimin Ao^*, Xi Fang, Lili Wei, Fei Li

Energy Engineering, Vol.119, No.3, pp. 985-996, 2022, DOI:10.32604/ee.2022.018185

Abstract Ground short circuit faults in current transmission lines are common in the power systems. In order to prevent the power system from aggravating the accident caused by short-circuit faults of transmission lines, a novel convolutional neural network (CNN) model is constructed to identify the short-circuit fault of the transmission line in the power system. The CNN model is mainly consisted of five convolutional layers, three max-pooling layers, one concatenate layer, one dropout layer, one fully connected layer, and a Softmax classifier. This method uses a fixed time window to intercept system short-circuit fault data, extracts the deep features of these… More >

Jiacheng Yang¹, Xiaohe Zhai¹, Zhongfu Tan^1,2,*, Zhenghao He¹

Energy Engineering, Vol.119, No.3, pp. 883-906, 2022, DOI:10.32604/ee.2022.018033

Abstract There is uncertainty in the electricity price of spot electricity market, which makes load aggregators undertake price risks for their agent users. In order to allow load aggregators to reduce the spot market price risk, scholars have proposed many solutions, such as improving the declaration decision-making model, signing power mutual insurance contracts, and adding energy storage and mobilizing demand-side resources to respond. In terms of demand side, calling flexible demand-side resources can be considered as a key solution. The user's power consumption rights (PCRs) are core contents of the demand-side resources. However, there have been few studies on the pricing… More >