Browsing by Author "Li, Wei"

Now showing 1 - 5 of 5
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    Data-centric predictive control with tuna swarm optimization-backpropagation neural networks for enhanced wind turbine performance
    (Elsevier, 2024-12) Li, Wei; Pandit, Ravi Kumar
    Wind energy is a significant renewable resource, but its efficient harnessing requires advanced control systems. This study presents a Data-Centric Predictive Control (DPC) system, enhanced by a Tuna Swarm Optimization-Backpropagation Neural Network (TSO-BPNN) for predictive wind turbine control. It's like a smart tool that uses innovative fusion of deep learning, predictive Control, and reinforcement learning. Unlike traditional control methods, the proposed approach uses real-time data to optimize turbine performance in response to fluctuating wind conditions. The system is validated using simulations on the FAST platform, which demonstrate its superior performance in two critical operational regions. Specifically, in Region II, where the objective is to maximize power extraction from the wind, the DPC achieves a 1.07 % reduction in overshoot and an improvement of 36.14 units in steady-state error compared to traditional methods. The response time remains comparable to existing Model Predictive Control (MPC) strategies, ensuring real-time applicability without sacrificing efficiency. In Region III, where maintaining constant power output is crucial, the DPC outperforms both the baseline and MPC methods, reducing overshoot by 0.58 % and improving accuracy by 17.27 units compared to the baseline method. These results highlight the effectiveness of the proposed DPC system in optimizing turbine performance under variable wind conditions, offering a significant improvement over traditional methods in both accuracy and control precision.
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    High performance perovskite sub-module with sputtered SnO2 electron transport layer
    (Elsevier, 2019-03-13) Bai, Guangfeng; Wu, Zhengli; Li, Jing; Bu, Tongle; Li, Wangnan; Li, Wei; Huang, Fuzhi; Zhang, Qi; Cheng, Yi-Bing; Zhong, Jie
    Hybrid perovskite solar cells (PSC) have gained stupendous achievement in single/tandem solar cell, semitransparent solar cell and flexible devices. Aiming for potential commercialization of perovskite photovoltaic technology, up scalable processing is crucial for all function layers in PSC. Herein we present a study on room temperature magnetron sputtering of tin oxide electron transporting layer (ETL) and apply it in a large area PSC for low cost and continues manufacturing. The SnO2 sputtering targets with varied oxygen and deposition models are used. Specifically, the working gas ratio of Ar/O2 during the radio frequency sputtering process plays a crucial role to obtain optimized SnO2 film. The sputtered SnO2 films demonstrate similar morphological and crystalline properties, but significant varied defect states and carrier transportation roles in the PSC devices. With further modification of thickness of SnO2, the PSCs based on sputtered SnO2 ETL shows a champion efficiency of 18.20% in small area and an efficiency of 14.71% in sub-module with an aperture area of 16.07 cm2, which is the highest efficiency of perovskite sub module with sputtered ETLs.
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    Modelling, simulation and optimal control for an aircraft of aileron-less folding wing
    (Wseas, 2008-10-31T00:00:00Z) Jiewang, Zheng; Guo, Shijun J.; Li, Wei
    The purpose of this paper is to discuss the method of modeling and control system design for a loitering aircraft of aileron-less folding wing. A nonlinear model of the aircraft was established, and then linearized by small disturbance method. The lateral-directional stability augmentation options were analyzed through the root locus plots. The pole placement method based on linear quadratic regulator (LQR) technology was used to achieve desirable dynamic characteristics. In the analysis, the state parameters which represent rapid oscillation states of the aircraft such as roll rate and yaw rate were set as primary control parameters in the inner loop. The states oscillated slowly such as rolling angle and yaw angle were set as main control parameters in the outer loop. Based on the self-organizing fuzzy control algorithm, the aircraft can be controlled to fly in a desired path. Two types of course control plan were investigated and verified. The results show that the control plans are feasible and the control system is adequately robust to meet the requirements of the course control.
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    More Electric Landing Gear Actuation Study
    (Cranfield University, 2009) Li, Wei; Fielding, John
    This report addresses the problem of landing gear actuation system design on more-electric aircraft (MEA). Firstly, information about more-electric aircraft and more-electric actuators was gathered and sorted. Current more-electric landing actuation system applications and researches were also summarized. Then several possible more-electric landing gear actuation concepts were identified. To evaluate these concepts, the case study method has been used. A concept aircraft “MRT7-T”, which has similar maximum takeoff weight to that of Boeing 787, has been chosen as the design case. Systems of different configurations and architectures were designed for this aircraft. In the end of this study, a comparison between different more-electric landing gear actuation systems, and also with traditional central hydraulic system was made. The best concept was proposed. More-electric actuation technology has made considerable progress in the last two decades. However, most of the applications and researches have focused on flight control actuation and brakes. Using more-electric drives for landing gear actuation has been well known to be difficult, for the reason of massive power needs and difficulties in achieving redundancy levels. Famous more-electric research projects like POA and Power-By-Wire only gave recommendation of using electro-hydrostatic actuators (EHA) in landing gear actuation. And no further information is available to the public. In this study, DHS (distributed hydraulic system), EHA (electro-hydrostatic actuator) and EMA (electro-mechanical actuator) were identified as candidate solutions. Design requirements such as retraction time, load and redundancy levels were derived through analysis. As a unique feature, landing gear kinematics concepts were also subject to optimization. Various kinematics concepts were proposed and analyzed in detail, to provide favorable loading and geometrical conditions for the systems. Kinematics design guidelines were built through discussion. Different motors such as AC induction motor, BDCM (brushless DC motor) and PMSM (permanent magnetic synchronous motor) were evaluated for use. Different system architectures were also explored. The multi-discipline optimization method has been extensively used in the design process of the systems. Firstly, each node of the actuation systems was optimized. Then optimizations were made to the systems. Performances of each system were analyzed in several aspects such as weight, power, reliability and maintenance. Comparison of different systems was made through scoring method. The results suggested that DHS, EHA and EMA are all applicable for landing gear actuation. And isolated EHA is the best.
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    Ultra dense satellite-enabled 6G networks: Resource optimization and interference management
    (IEEE, 2023-05-10) Liu, Xiangnan; Zhang, Haijun; Sheng, Min; Li, Wei; Al-Rubaye, Saba; Long, Keping
    With the evolution of the sixth generation (6G) mobile communication technology, ample attention has gone to the integrated terrestrial-satellite networks. This paper notes that four typical application scenarios of integrated terrestrial-satellite networks are integrated into ultra dense satellite-enabled 6G networks architecture. Then the subchannel and power allocation schemes for the downlink of the ultra dense satellite-enabled 6G heterogeneous networks are introduced. Satellite mobile edge computing (SMEC) with edge caching in three-layer heterogeneous networks serves to reduce the link traffic of networks. Furthermore, a scheme for interference management is presented, involving quality-of-service (QoS) and co-tier/cross-tier interference constraints. The simulation results show that the proposed schemes can significantly increase the total capacity of ultra dense satellite-enabled 6G heterogeneous networks.