Na Yu¹, Changzheng Gao², Xiuna Wang², Dongwei Li^2,*, Weiyang You²

Energy Engineering, Vol.120, No.12, pp. 2879-2901, 2023, DOI:10.32604/ee.2023.029426

Abstract With the goal of “carbon peaking and carbon neutralization”, it is an inevitable trend for investing smart grid to promote the large-scale grid connection of renewable energy. Smart grid investment has a significant driving effect (derivative value), and evaluating this value can help to more accurately grasp the external effects of smart grid investment and support the realization of industrial linkage value with power grid investment as the core. Therefore, by analyzing the characterization of the derivative value of smart grid driven by investment, this paper constructs the evaluation index system of the derivative value of smart grid investment including… More >

Jiarui Wu¹, Yuzhen Kang², Junxiao Feng^1,*

Energy Engineering, Vol.120, No.12, pp. 2783-2802, 2023, DOI:10.32604/ee.2023.029358

Abstract To enhance system stability, solar collectors have been integrated with air-source heat pumps. This integration facilitates the concurrent utilization of solar and air as energy sources for the system, leading to an improvement in the system's heat generation coefficient, overall efficiency, and stability. In this study, we focus on a residential building located in Lhasa as the target for heating purposes. Initially, we simulate and analyze a solar-air source heat pump combined heating system. Subsequently, while ensuring the system meets user requirements, we examine the influence of solar collector installation angles and collector area on the performance of the solar-air… More >

Haoliang Yang^*, Yonggang Dong, Zhifang Yang

Energy Engineering, Vol.120, No.12, pp. 2917-2931, 2023, DOI:10.32604/ee.2023.029167

Abstract Reducing the impact of power outages and maintaining the power supply duration must be considered in implementing emergency energy dispatching in micro-networks. This paper studies a new emergency energy treatment method based on the robust optimal method and the industrial park micro-network with the optical energy storage system. After controlling the load input, a control strategy of adjusting and removing is proposed. Rolling optimal theory is applied to emergency energy scheduling based on a robust optimal mathematical model. A weighting factor is introduced into the optimal model to balance the importance of reducing and retaining the power supply. Uncertainty is… More >

Xiaobao Yu^*, Kang Yang

Energy Engineering, Vol.120, No.12, pp. 2741-2760, 2023, DOI:10.32604/ee.2023.028041

Abstract Taking an industrial park as an example, this study aims to analyze the characteristics of a distribution network that incorporates distributed energy resources (DERs). The study begins by summarizing the key features of a distribution network with DERs based on recent power usage data. To predict and analyze the load growth of the industrial park, an improved back-propagation algorithm is employed. Furthermore, the study classifies users within the industrial park according to their specific power consumption and supply requirements. This user segmentation allows for the introduction of three constraints: node voltage, wire current, and capacity of DERs. By incorporating these… More >

Kehuan Xie¹, Longhai Yu^2,3, Chuanchang Li^1,*

Energy Engineering, Vol.120, No.12, pp. 2903-2915, 2023, DOI:10.32604/ee.2023.027636

Abstract Vanadium redox flow battery (VRFB) is considered one of the most potential large-scale energy storage technologies in the future, and its electrolyte flow rate is an important factor affecting the performance of VRFB. To study the effect of electrolyte flow rate on the performance of VRFB, the hydrodynamic model is established and a VRFB system is developed. The results show that under constant current density, with the increase of electrolyte flow rate, not only the coulombic efficiency, energy efficiency, and voltage efficiency will increase, but also the capacity and energy discharged by VRFB will also increase. But on the other… More >

Tianfeng Xu¹, Tao Wang¹, Chengming Ye², Jing Zhang¹, Peng Xi¹, Yunhui Chen², Gengwu Zhang^3,*

Energy Engineering, Vol.120, No.11, pp. 2629-2650, 2023, DOI:10.32604/ee.2023.027537

Abstract In order to improve the reliability of power supply, the sophisticated design of the structure of electric cable network has become an important issue for modern urban distribution networks. In this paper, an electric cable path planning model based on heuristic optimization algorithm considering mixed-land scenario is proposed. Firstly, based on different land samples, the kernel density estimation (KDE) and the analytic hierarchy process (AHP) are used to estimate the construction cost of each unit grid, in order to construct the objective function of comprehensive investment for electric cable loop network. Then, the ant colony optimization (ACO) was improved in… More >

Weigang Jin¹, Lei Chen^2,*, Yifei Li², Shencong Zheng², Yuqi Jiang², Hongkun Chen²

Energy Engineering, Vol.120, No.11, pp. 2469-2487, 2023, DOI:10.32604/ee.2023.043021

Abstract Along with the increasing integration of renewable energy generation in AC-DC power networks, investigating the dynamic behaviors of this complex system with a proper equivalent model is significant. This paper presents an equivalent modeling method for the AC-DC power networks with doubly-fed induction generator (DFIG) based wind farms to decrease the simulation scale and computational burden. For the AC-DC power networks, the equivalent modeling strategy in accordance with the physical structure simplification is stated. Regarding the DFIG-based wind farms, the equivalent modeling based on the sequential identification of multi-machine parameters using the improved chaotic cuckoo search algorithm (ICCSA) is conducted.… More >

Xueting Cheng¹, Ziqi Zhang^2,*, Yueshuang Bao¹, Huiping Zheng¹

Energy Engineering, Vol.120, No.11, pp. 2517-2529, 2023, DOI:10.32604/ee.2023.042633

Abstract At present, the proportion of new energy in the power grid is increasing, and the random fluctuations in power output increase the risk of cascading failures in the power grid. In this paper, we propose a method for identifying high-risk scenarios of interlocking faults in new energy power grids based on a deep embedding clustering (DEC) algorithm and apply it in a risk assessment of cascading failures in different operating scenarios for new energy power grids. First, considering the real-time operation status and system structure of new energy power grids, the scenario cascading failure risk indicator is established. Based on… More >

Decheng Li¹, Yan Zhang², Dongdong Ma², Haozhe Geng¹, Yu Wu^1,2,*

Energy Engineering, Vol.120, No.11, pp. 2503-2516, 2023, DOI:10.32604/ee.2023.041803

Abstract The fracturing process of sandstone is inherently complex due to its loose internal structure and deformation adaptability. Liquid nitrogen pre-injection has emerged as a promising approach to damage reservoir rocks, effectively reducing fracture pressure and establishing intricate fracture networks, thus offering a potential solution for reservoir reconstruction. To unravel the fundamental mechanisms governing sandstone fracturing behaviors following liquid nitrogen pre-injection, sandstone fracturing experiments were conducted under varying durations of liquid nitrogen injection, rock temperature, and in-situ stress conditions. The experiments showcased the evolution of injection pressure and fracture characteristics under different testing conditions, complemented by electron microscope analysis to elucidate… More >

Wenyang Tang^1,2, Cong Liu^1,*, Bo Zhang²

Energy Engineering, Vol.120, No.11, pp. 2667-2681, 2023, DOI:10.32604/ee.2023.040743

Abstract Harsh working environments and wear between blades and other unit components can easily lead to cracks and damage on wind turbine blades. The cracks on the blades can endanger the shafting of the generator set, the tower and other components, and even cause the tower to collapse. To achieve high-precision wind blade crack detection, this paper proposes a crack fault-detection strategy that integrates Gated Residual Network (GRN), a fusion module and Transformer. Firstly, GRN can reduce unnecessary noisy inputs that could negatively impact performance while preserving the integrity of feature information. In addition, to gain in-depth information about the characteristics… More >