Article
Economics
Malte Lehna, Fabian Scheller, Helmut Herwartz
Summary: The variability of the day-ahead electricity spot price has increased due to the significant increase in renewable energies in electricity production. In this study, four different approaches, including (S)ARIMA(X), LSTM, CNN-LSTM, and VAR models, were compared for forecasting the German day-ahead electricity spot price. The LSTM model achieved the best overall forecasting performance, while the two-stage VAR model performed well for shorter prediction horizons. Moreover, combining both methods resulted in improved electricity spot price forecasts.
Article
Environmental Sciences
Haoyu Jiang, Zheng Yang
Summary: A well-performed look-up table model was established to study the climate and variability of wind-sea and swell globally. Swells dominate the World Ocean and have different responses compared to wind-seas for the same atmospheric oscillation. Significant positive/negative long-term trends of H-WS/H-SW were found in most regions.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Computer Science, Information Systems
Yong-Chao Jin, Qian Cao, Ke-Nan Wang, Yuan Zhou, Yan-Peng Cao, Xi-Yin Wang
Summary: COVID-19 has become a global public health emergency, leading to restrictions in many countries and resulting in millions of infections and thousands of deaths worldwide. The virus has also significantly impacted social and economic activities. The elderly and those with existing medical issues are particularly vulnerable to the effects of COVID-19.
Article
Thermodynamics
Fubin Chen, Wen Kang, Zhenru Shu, Qiusheng Li, Yi Li, Y. Frank Chen, Kang Zhou
Summary: This study uses a combination of BPNN and POD to predict surface wind pressure, showing that the POD-BPNN model can be used as a useful tool for wind pressure prediction.
BUILDING SIMULATION
(2022)
Article
Oceanography
Rui Li, Kejian Wu, Jingkai Li, Xianghui Dong, Jian Sun, Wenqing Zhang, Qingxiang Liu
Summary: This study analyzed the spatial characteristics of wind waves and swells in the Indian Ocean using the ERA-5 40-year reanalysis data set. The study found a strong correlation between zonal surface Stokes drift and wind waves, as well as a strong correlation between the Indian Ocean Dipole (IOD) and surface Stokes drift. The depth-integrated wave transport was also found to have a significant impact on sea surface temperature.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Thermodynamics
Jikai Duan, Hongchao Zuo, Yulong Bai, Jizheng Duan, Mingheng Chang, Bolong Chen
Summary: This study presents a novel hybrid forecasting system that significantly enhances the accuracy of wind speed prediction, achieving superior prediction results compared to other models through a process of decomposition, prediction, and error correction.
Article
Environmental Sciences
Hector Lobeto, Melisa Menendez, Inigo J. Losada
Summary: The study compares present and future wind-wave conditions under a high-emission scenario using a novel approach and finds an increase in energy from Southern Ocean swells globally, which is especially relevant for the west coast of North America. On the other hand, a consistent decrease in the energy of large northern Atlantic swells near the equator is observed.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Yuqi Wu, Chenqing Fan, Qiushuang Yan, Junmin Meng, Tianran Song, Jie Zhang
Summary: In this paper, the effects of wind wave spectra, non-Gaussianity of the sea surface, and swell on the distribution of the facet normalized radar cross section (NRCS) are analyzed. The results show that the Apel spectrum achieves a more consistent NRCS distribution at low incidence angles, while the composite spectra perform better at high incidence angles under VV polarization. The modified TSM successfully predicts the upwind-downwind asymmetry of backscattering and the distribution of scattering simulated by the modified TSM deviates significantly from the Gaussian distribution.
Article
Computer Science, Artificial Intelligence
Zhi-wu Dou, Ming-xin Ji, Man Wang, Ya-nan Shao
Summary: Pu'er tea, a geographical indication product from Yunnan, holds the top brand value in China. This study employs ARIMA for short-term price prediction and BP model for long-term prediction based on 16 factors' ranking using TOPSIS method. Suggestions for the industry include reducing production capacity, increasing consumer demand, and utilizing internet for promotion.
NEURAL COMPUTING & APPLICATIONS
(2022)
Article
Computer Science, Artificial Intelligence
Chenxi Li, Zhaohui Li, Meng Wu
Summary: In this article, the application of supply chain information sharing and genetic algorithm back propagation neural networks in supply chain management is studied. The concepts and characteristics of supply chain information sharing and genetic algorithm back propagation neural networks are explained. The feasibility of using BP neural network to evaluate supply chain information sharing is analyzed. An assessment indicator system for supply chain information sharing is constructed from four aspects. The principle and algorithm of BP neural network are analyzed, and a network model is constructed.
Article
Engineering, Marine
Wenyi Meng, Shuiqing Li, Xuan Wang, Haoyu Jiang
Summary: In this study, three existing methods to separate wind-sea and swell from 1D wave spectra were evaluated statistically using data from 38 meteorological buoys. Among the three methods, the PM method shows the best agreement with the 2D separation method. A new 1D wind-sea-swell separation method based on deep learning is proposed, which outperforms all existing 1D separation methods. Both methods are robust and have no significant geographical dependence.
Article
Meteorology & Atmospheric Sciences
Antoine Villefer, Michel Benoit, Damien Violeau, Maria Teles
Summary: The wind wave peak frequency in a wind wave tunnel decreases when irregular long paddle-waves are added to the sea state. The TOMAWAC model is used to assess this frequency downshift at prototype scale in bimodal sea-state conditions. The model successfully reproduces laboratory experiments and coastal observations, particularly when using the latest developments in spectral wave models for whitecapping dissipation and nonlinear interactions.
Article
Engineering, Marine
Xin Zhang, Kejian Wu, Rui Li, Shuai Zhang, Ruyan Zhang, Jin Liu, Alexander V. Babanin
Summary: This study analyzes the spatial and temporal distribution of ocean waves in the North Pacific and confirms the presence of an ENSO signal. The study also reveals the spatial distributions of swells and wind waves and their transport of signals to lower latitudes.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Environmental Sciences
Sachini Pathirana, Ian Young, Alberto Meucci
Summary: Ocean wave swell generated near Campbell Island in the Southern Ocean is tracked across the Pacific Ocean. Data from a wave buoy at Campbell Island provides information on the directional spectrum. Sentinel-1 SAR and CFOSAT satellite data are used to measure the swell at multiple locations along 19 Great Circle paths. The WAVEWATCH III wave model is employed to study the physical processes involved in the propagation and decay of the swell, revealing an overestimation in current spectral wave models and the need for further research.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Computer Science, Hardware & Architecture
Hanyu Yang, Xutao Li, Wenhao Qiang, Yuhan Zhao, Wei Zhang, Chang Tang
Summary: This paper proposes a network traffic prediction method based on SA optimized ARIMA-BPNN, which improves the accuracy of network traffic prediction by comprehensively using linear and non-linear models as well as optimization algorithm.
Article
Engineering, Electrical & Electronic
Puyu Wang, Pengcheng Liu, Tianming Gu, Ningqiang Jiang, Xiao-Ping Zhang
Summary: This paper investigates the small-signal stability of a DC current flow controller (CFC) integrated meshed multi-terminal HVDC (MTDC) system. The unique contributions include considering the dynamics of the CFC, interconnected voltage-source converters (VSCs), and the DC transmission lines in the small-signal modeling, identifying the switching effect of capacitive components in the pi-type DC transmission lines, taking into account the impact of the CFC on the AC side of the MTDC system, and investigating the influence of the CFC control system/structural parameters on the small-signal stability of the entire system. The proposed method is verified to be effective in different MTDC systems with CFC and useful for the configuration and parametric design of CFC integrated meshed MTDC systems.
IEEE TRANSACTIONS ON POWER SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Guolong Ma, Jianing Li, Xiao-Ping Zhang
Summary: In this paper, an energy storage system (ESS) capacity optimization model considering the internal energy autonomy indicator and grid supply point (GSP) resilience management method is proposed. A three-stage coupled model is established, including investment decision, day-ahead operation strategy, and real-time power fluctuation smoothing control. The effectiveness of the proposed model is verified through simulations.
IEEE TRANSACTIONS ON SMART GRID
(2023)
Article
Green & Sustainable Science & Technology
Qirun Sun, Zhi Wu, Wei Gu, Xiao-Ping Zhang, Pengxiang Liu, Guangsheng Pan, Haifeng Qiu
Summary: This paper proposes a tri-level multi-energy system planning method for zero energy buildings (ZEBs) that considers long- and short-term uncertainties. The method tackles long-term temperature change and short-term source-load uncertainties separately. It generates representative scenarios for long-term uncertainties and applies a hybrid stochastic and robust optimization (HSRO) method for short-term uncertainties. The simulation results verify the effectiveness of the proposed planning method.
IEEE TRANSACTIONS ON SUSTAINABLE ENERGY
(2023)
Article
Energy & Fuels
Mohamed Alashqar, Conghuan Yang, Ying Xue, Zhaoxi Liu, Weiye Zheng, Xiao-Ping Zhang
Summary: The increasing electricity demand necessitates the installation of more generating units in the grid. However, this leads to fault current levels exceeding the limits of electrical equipment, especially in interconnected grids. Existing solutions have drawbacks, while the superconducting fault current limiter (SFCL) shows promise. This paper proposes the use of the resistive SFCL to enhance the stability of an interconnected power system, with a case study conducted on a two-area system to analyze the optimal value and locations of the SFCL. Results demonstrate that the system remains stable without the need for tuning the power system stabilizer (PSS).
FRONTIERS IN ENERGY RESEARCH
(2023)
Article
Engineering, Electrical & Electronic
Nan Chen, Yuefeng Yang, Lanfang Li, Chunyan Cui, Ying Xue, Xiao-Ping Zhang
Summary: This paper proposes a new commutation voltage calculation method for asymmetrical faults in Multi-Infeed LCC-HVDC systems. It also introduces CF prediction criteria based on the Voltage-Time Area (VTA) theory and a calculation method for the extra commutation voltage needed for each inverter to avoid CF. Simulation results using the CIGRE LCC-HVDC Benchmark system and a six-machine-two-area (6M2A) test system demonstrate the effectiveness of the proposed methods.
IEEE TRANSACTIONS ON POWER DELIVERY
(2023)
Article
Green & Sustainable Science & Technology
Chenyixuan Ni, Laijun Chen, Xiaotao Chen, Junyi Zhai, Shengwei Mei, Xiao-Ping Zhang
Summary: This paper proposes a novel solar-thermal-assisted AA-CAES (ST-AA-CAES) system that integrates variable thermal energy storage to improve system efficiency. The results show that the electric-to-electric conversion efficiency, round-trip efficiency, and exergy efficiency of ST-AA-CAES can reach 56.4%, 95.5%, and 55.9%, respectively. The article also demonstrates the exergy efficiency and destruction details of each subsystem. The particle swarm optimization algorithm is applied to analyze the economic feasibility of optimizing integrated energy systems, offering high accuracy, convenient implementation, and fast convergence. The system can be applied in areas with abundant solar energy resources, providing high efficiency and multi-energy supply capability.
IET RENEWABLE POWER GENERATION
(2023)
Article
Engineering, Electrical & Electronic
Senlin Yu, Xiaoru Wang, Xiao-Ping Zhang
Summary: This paper proposes a fault detection method based on the ratio of voltage integrals to improve the sensitivity of the single-end method to high-resistance faults, ensuring the continuous and reliable operation of the modular multilevel converter (MMC)-based HVDC grid during dc faults.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Junyi Zhai, Yuning Jiang, Xiao Chen, Jianing Li, Colin N. Jones, Xiao-Ping Zhang
Summary: This paper focuses on the decentralized adjustable robust operation problem for multi-area integrated electricity and natural gas systems (IEGS). It proposes an asynchronous alternating direction method of multipliers (ADMM) based decentralized model that allows each area to perform local updates with information from a subset of neighbors, solving the synchronization and heterogeneity issues of existing distributed algorithms. The combination of linear decision rules (LDRs) and automatic generation control (AGC) systems is also introduced to effectively handle renewable energy uncertainty.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Zhi Wu, Yiqi Li, Wei Gu, Zengbo Dong, Jingtao Zhao, Weiliang Liu, Xiao-Ping Zhang, Pengxiang Liu, Qirun Sun
Summary: This paper proposes a multi-timescale voltage control scheme using multi-agent deep reinforcement learning. Through assigning control variables to multiple agents and applying the Gumbel-Softmax distribution, the scheme achieves the effect of distributed control. By centralized learning and decentralized execution, the scheme can obtain the optimal coordinated control strategy of multiple regulators adaptively. Case studies conducted on the modified IEEE-123 bus system show that the MADRL-based method outperforms other methods.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Suhan Zhang, Wei Gu, Xiao-Ping Zhang, Hai Lu, Ruizhi Yu, Haifeng Qiu, Shuai Lu
Summary: This paper introduces the effectiveness of the dynamic simulation of integrated electricity and gas systems in accurate operational guidance, and proposes a novel adaptive step size control strategy for variable-coefficient partial differential equation solvers.
IEEE TRANSACTIONS ON SMART GRID
(2023)
Article
Energy & Fuels
Yue Qiu, Suyang Zhou, Wei Gu, Yuping Lu, Xiao-Ping Zhang, Gaoyan Han, Kang Zhang, Hongkun Lyu
Summary: This paper investigates the effects of hydrogen-enriched compressed natural gas (HCNG) on the dynamics of the gas network and proposes an improved model for the HCNG network. It also introduces an optimal dispatch model for the electricity-HCNG-integrated energy system (E-HCNG-IES) considering the HCNG supply chain. The proposed methodology is evaluated through numerical testbeds, demonstrating the economic and environmental benefits of increasing hydrogen volume fraction in the E-HCNG-IES.
CSEE JOURNAL OF POWER AND ENERGY SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Xin Ma, Conghuan Yang, Xiao-Ping Zhang, Ying Xue, Jianing Li
Summary: This paper proposes full Double-Precision and Mixed-Precision Floating-Point schemes for real-time Electromagnetic Transients (EMT) simulation on FPGA platform, aiming to achieve optimal balance between numerical accuracy and computational resource cost. Through experimental comparison on rotating and non-rotating components, it is found that full Double-Precision has advantages in addressing phase shift problem. The proposed system-level Mixed-Precision scheme can achieve close accuracy to full Double-Precision scheme with 20% average reduction in resource consumption.
IEEE TRANSACTIONS ON POWER SYSTEMS
(2023)
Proceedings Paper
Energy & Fuels
Hussaini Ali Adamu, Xiao-Ping Zhang
Summary: The conventional weighted least squares (WLS) power system state estimation algorithm often uses the same weights, causing significant deviation compared to the true solution. This paper proposes a new 3-phase re-weighted nonlinear regression method that incorporates the Welsch weight function to minimize the deviation caused by measurement errors. The proposed method outperforms the conventional state estimation method in terms of feasibility and estimation accuracy.
2023 IEEE 3RD INTERNATIONAL CONFERENCE IN POWER ENGINEERING APPLICATIONS, ICPEA
(2023)
Review
Engineering, Electrical & Electronic
Zixuan Jia, Jianing Li, Xiao-Ping Zhang, Ray Zhang
Summary: The rapid development of electric vehicles (EVs) is due to the increased focus on clean energy and environmental protection by countries and regions. This paper focuses on the optimization of EV charging, which poses new challenges to local power systems. Uncoordinated EV charging increases peak-to-valley load differences, harmonic distortions, and affects auxiliary services. To stabilize power grids, studies have been conducted on EV charging forecasting and coordinated charging strategies. The paper reviews these studies and provides recommendations for addressing EV charging challenges.
JOURNAL OF MODERN POWER SYSTEMS AND CLEAN ENERGY
(2023)
Article
Engineering, Electrical & Electronic
James Naughton, Shariq Riaz, Michael Cantoni, Xiao-Ping Zhang, Pierluigi Mancarella
Summary: This paper proposes a comprehensive optimization-based techno-economic assessment of a hybrid renewable electricity-hydrogen virtual power plant (VPP) to deliver hydrogen at a lower net cost. The study shows the importance of value stacking for driving down the cost of cleaner hydrogen and highlights the significant boost in business case through multi-market participation. The research also suggests that hybrid VPPs will further improve their business cases if high price volatility continues.
JOURNAL OF MODERN POWER SYSTEMS AND CLEAN ENERGY
(2023)
