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Department of Electrical and Electronic Engineering
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1.Speed Tracking Based Energy-Efficient Freight Train Control Through Multi-Algorithms Combination

Author:Yang, J;Jia, LM;Fu, YX;Lu, SF


Abstract:Based on the characteristics of freight train control, which are nonlinear, time-delay, with multi-constraint and multiobjective, this paper focuses on speed tracking problem. Firstly, in a gradual process, a multi-modal fuzzy PID (MM-FPID) control algorithm is presented on the basis of a brief analysis of PI and PID control, which is generally used to train control in active services. Secondly, in order to deal with the time-delay problem of freight train, the paper adopts an approach of traction force feed-forward, which greatly improves the dynamic performance of the controller. Thirdly, for the overspeed brake problem caused by speed overshoot, the strategy of adaptive traction force limitation is adopted, and we get satisfactory results without increasing the safety speed margin. Fourthly, inspired by the selflearning characteristic of neural networks (NNs), an integrated controller of MM-FPID and NNs is proposed. Finally, with the help of a computer simulation platform, the paper puts forward a set of simulations, comparing the MM-FPID and the integrated control method with classical PID and fuzzy control. The results show that both MM-FPID and the integrated controller has satisfactory control effect, and their multi-modal structure makes it easy to fit different applications well, while the integrated controller has more potential in self-learning.

2.Minimum-Backflow-Power Scheme of DAB-Based Solid-State Transformer With Extended-Phase-Shift Control

Author:Shi, HC;Wen, HQ;Chen, J;Hu, YH;Jiang, L;Chen, GP;Ma, JM


Abstract:As key component for the flexible dc distributed power system, the dual active bridge (DAB)-converter-based solid-state transformer (SST) with high efficiency for a wide operating range is essential. However, with the traditional phase-shift control, high backflow power and current stress will significantly affect the conversion efficiency. In this paper, the backflow power characteristics in both sides of DAB-based SST converters are comprehensively analyzed. On this basis, complete transmission power, backflow power, and peak current mathematical models are established. Then, a minimum-backflow-power-based extended-phase-shift control strategy is proposed with the determination of optimal phase-shift pairs by using the Karush-Kuhn-Tucker function for various scenarios. The backflow power and current stress curves with different algorithms are compared. It shows the proposed control can improve the output power regulation flexibility, minimize the backflow power, and improve the efficiency in wide operating range. Finally, a DAB-based SST prototype was developed and the experimental results verified the effectiveness of the proposed control strategy.

3.Electrical and Electronic Technologies in More-Electric Aircraft: A Review

Author:Ni, K;Liu, YJ;Mei, ZB;Wu, TH;Hu, YH;Wen, HQ;Wang, YG

Source:IEEE ACCESS,2019,Vol.7

Abstract:This paper presents a review of the electrical and electronic technologies investigated in more-electric aircraft (MEA). In order to change the current situation of low power efficiency, serious pollution, and high operating cost in conventional aircraft, the concept of MEA is proposed. By converting some hydraulic, mechanical, and pneumatic power sources into electrical ones, the overall power efficiency is greatly increased, and more flexible power regulation is achieved. The main components in an MEA power system are electrical machines and power electronics devices. The design and control methods for electrical machines and various topologies and control strategies for power electronic converters have been widely researched. Besides, several studies are carried out regarding energy management strategies that intend to optimize the operation of MEA power distribution systems. Furthermore, it is necessary to investigate the system stability and reliability issues in an MEA, since they are directly related to the safety of passengers. In terms of machine technologies, power electronics techniques, energy management strategies, and the system stability and reliability, a review is carried out for the contributions in the literature to MEA.

4.Multi-Step Short-Term Power Consumption Forecasting with a Hybrid Deep Learning Strategy

Author:Yan, K;Wang, XD;Du, Y;Jin, N;Huang, HC;Zhou, HX


Abstract:Electric power consumption short-term forecasting for individual households is an important and challenging topic in the fields of AI-enhanced energy saving, smart grid planning, sustainable energy usage and electricity market bidding system design. Due to the variability of each household's personalized activity, difficulties exist for traditional methods, such as auto-regressive moving average models, machine learning methods and non-deep neural networks, to provide accurate prediction for single household electric power consumption. Recent works show that the long short term memory (LSTM) neural network outperforms most of those traditional methods for power consumption forecasting problems. Nevertheless, two research gaps remain as unsolved problems in the literature. First, the prediction accuracy is still not reaching the practical level for real-world industrial applications. Second, most existing works only work on the one-step forecasting problem; the forecasting time is too short for practical usage. In this study, a hybrid deep learning neural network framework that combines convolutional neural network (CNN) with LSTM is proposed to further improve the prediction accuracy. The original short-term forecasting strategy is extended to a multi-step forecasting strategy to introduce more response time for electricity market bidding. Five real-world household power consumption datasets are studied, the proposed hybrid deep learning neural network outperforms most of the existing approaches, including auto-regressive integrated moving average (ARIMA) model, persistent model, support vector regression (SVR) and LSTM alone. In addition, we show a k-step power consumption forecasting strategy to promote the proposed framework for real-world application usage.

5.Comproportionation Reaction Synthesis to Realize High-Performance Water-Induced Metal-Oxide Thin-Film Transistors

Author:Liu, QH;Zhao, C;Mitrovic, IZ;Xu, WY;Yang, L;Zhao, CZ


Abstract:Solution-processed metal-oxide thin films have been widely studied in low-power and flexible electronics. However, the high temperature required to form a condensed and uniform film limits their applications in flexible and low-cost electronics. Here, a novel and environmental-friendly comproportionation reaction synthesis (CRS) is presented to obtain amorphous aluminum oxide (AlOx) thin films for solution-processed thin-film transistors (TFTs) employing water as the precursor solvent. The thermal decomposition of CRS-AlO(x)precursor is completed at approximate to 300 degrees C, which is 100 degrees C lower than that of the conventional water-induced AlOx. The morphological, optical, compositional, and electrical properties of CRS-AlO(x)dielectric films are studied systematically. Meanwhile, TFTs based on water-induced In(2)O(3)metal oxide semiconductor layers deposited on these dielectrics at low temperatures are formed and characterized. Compared with TFTs based on conventional AlO(x)showing low mobility and low clockwise hysteresis, In2O3TFTs based on CRS-AlO(x)exhibit improved electrical performance and counterclockwise hysteresis in the transfer curves. Water-induced TFTs fabricated on CRS-AlO(x)formed at a low temperature of 250 degrees C have average mobility of 98 cm(2)V(-1)s(-1). Through chemical composition characterization and electrical characterization, the high mobilities of TFTs based on CRS-AlO(x)dielectrics are correlated to trap states, which resulted in counterclockwise hysteresis in the transfer curves.

6.Review on Non-Volatile Memory with High-k Dielectrics: Flash for Generation Beyond 32 nm

Author:Zhao, C;Zhao, CZ;Taylor, S;Chalker, PR


Abstract:Flash memory is the most widely used non-volatile memory device nowadays. In order to keep up with the demand for increased memory capacities, flash memory has been continuously scaled to smaller and smaller dimensions. The main benefits of down-scaling cell size and increasing integration are that they enable lower manufacturing cost as well as higher performance. Charge trapping memory is regarded as one of the most promising flash memory technologies as further down-scaling continues. In addition, more and more exploration is investigated with high-k dielectrics implemented in the charge trapping memory. The paper reviews the advanced research status concerning charge trapping memory with high-k dielectrics for the performance improvement. Application of high-k dielectric as charge trapping layer, blocking layer, and tunneling layer is comprehensively discussed accordingly.

7.Interactive Learning Environment for Bio-Inspired Optimization Algorithms for UAV Path Planning

Author:Duan, HB;Li, P;Shi, YH;Zhang, XY;Sun, CH


Abstract:This paper describes the development of BOLE, a MATLAB-based interactive learning environment, that facilitates the process of learning bio-inspired optimization algorithms, and that is dedicated exclusively to unmanned aerial vehicle path planning. As a complement to conventional teaching methods, BOLE is designed to help students consolidate the concepts taught in the course and motivate them to explore relevant issues of bio-inspired optimization algorithms through interactive and collaborative learning processes. BOLE differs from other similar tools in that it places greater emphasis on fundamental concepts than on complex mathematical equations. The learning tasks using BOLE can be classified into four steps: introduction, recognition, practice, and collaboration, according to task complexity. It complements traditional classroom teaching, enhancing learning efficiency and facilitating the assessment of student achievement, as verified by its practical application in an undergraduate course "Bio-Inspired Computing." Both objective and subjective measures were evaluated to assess the learning effectiveness.

8.Minimize Reactive Power Losses of Dual Active Bridge Converters using Unified Dual Phase Shift Control

Author:Wen, HQ;Su, B


Abstract:This paper proposed an unified dual-phase-shift (UDPS) control for dual active bridge (DAB) converters in order to improve efficiency for a wide output power range. Different operating modes of UDPS are characterized with respect to the reactive current distribution. The proposed UDPS has the same output power capability with conventional phase-shift (CPS) method. Furthermore, its implementation is simple since only the change of the leading phase-shift direction is required for different operating power range. The proposed UDPS control can minimize both the inductor rms current and the circulating reactive current for various voltage conversion ratios and load conditions. The optimal phase-shift pairs for two bridges of DAB converter are derived with respect to the comprehensive reactive power loss model, including the reactive components delivered from the load and back to the source. Simulation and experimental results are illustrated and explained with details. The effectiveness of the proposed method is verified in terms of reactive power losses minimization and efficiency improvement.

9.Robust Localisation of Pedestrians with Cast Shadows Using Homology in A Monocular View

Author:Xu, M;Jia, TY;Lu, L;Smith, JS


Abstract:In this paper an object detection algorithm is proposed, which is robust in the presence of cast shadows and is based on geometric projections. The novelty of the work lies in the use of homology mapping of the foreground regions between different parallel planes within a monocular view, unlike some existing algorithms which depend on the use of multiple cameras. The results on an open video dataset are provided.

10.Segregated Lightweight Dynamic Rate (SLDR) control scheme for efficient internet communications

Author:Ting,T. O.;Ting,H. C.;Lee,Sanghyuk

Source:Lecture Notes in Electrical Engineering,2013,Vol.235 LNEE

Abstract:This paper proposes an effective Segregated Lightweight Dynamic Rate Control Scheme (SLDRCS) over the internet. Based on the feedback analysis of the current approaches, we found that the indicator of the congestion is only the queue length. It only captures a partial indicator of delay and loss in feedback mechanism. This may result in an ineffective way in controlling the network when congestion control occurs. Therefore, we suggest multiple congestion indicators to adapt inside this scheme to fully control the average delay and loss from bidirectional of sender to receiver. The behavior of next event packet being control using discrete event simulation tool with First Come First Serve (FCFS) scheduling policy and we code this algorithm into C programming language. Through the simulation results, our Segregated Lightweight Dynamic Rate Control Scheme (SLDRCS) guaranteed high improvement in packet drop and average delay under various congestion level and traffic load conditions compare with the current approach. © 2013 Springer Science+Business Media Dordrecht.

11.Hydrogen Consumption Minimization for Fuel Cell Trains Based on Speed Trajectory Optimization

Author:Huang, Zheng ; Wu, Chaoxian ; Lu, Shaofeng ; Xue, Fei

Source:Lecture Notes in Electrical Engineering,2020,Vol.638

Abstract:To make rail transport much greener, the fuel cell system has been applied in some train vehicles. The paper is aimed at establishing an integrated mixed-integer linear programming (MILP) model to optimize operations of the trains with the fuel cell system. Train motion analysis and physical constraints setup are given to illustrate the model. The main power-efficiency characteristic of the fuel cell system is also modeled in the research. The optimal train speed trajectory is obtained by applying the proposed approach, where the hydrogen consumption of the fuel cell is minimized. To prove the robustness of the model, the power profiles of scenarios with normal and extreme power-efficiency characteristics are compared, and the results show influences of these characteristics on the train operations. © Springer Nature Singapore Pte Ltd. 2020.

12.Emerging research on swarm intelligence and algorithm optimization

Author:Shi, Yuhui

Source:Emerging Research on Swarm Intelligence and Algorithm Optimization,2014,Vol.

Abstract:Throughout time, scientists have looked to nature in order to understand and model solutions for complex real-world problems. In particular, the study of self-organizing entities, such as social insect populations, presents a new opportunity within the field of artificial intelligence. Emerging Research on Swarm Intelligence and Algorithm Optimization discusses current research analyzing how the collective behavior of decentralized systems in the natural world can be applied to intelligent system design. Discussing the application of swarm principles, optimization techniques, and key algorithms being used in the field, this publication serves as an essential reference for academicians, upper-level students, IT developers, and IT theorists. © 2015 by IGI Global. All rights reserved.

13.Effect of Annealing Temperature for Ni/AlOx/Pt RRAM Devices Fabricated with Solution-Based Dielectric

Author:Shen, ZJ;Qi, YF;Mitrovic, IZ;Zhao, CZ;Hall, S;Yang, L;Luo, T;Huang, YB;Zhao, C


Abstract:Resistive random access memory (RRAM) devices with Ni/AlOx/Pt-structure were manufactured by deposition of a solution-based aluminum oxide (AlOx) dielectric layer which was subsequently annealed at temperatures from 200 degrees C to 300 degrees C, in increments of 25 degrees C. The devices displayed typical bipolar resistive switching characteristics. Investigations were carried out on the effect of different annealing temperatures for associated RRAM devices to show that performance was correlated with changes of hydroxyl group concentration in the AlOx thin films. The annealing temperature of 250 degrees C was found to be optimal for the dielectric layer, exhibiting superior performance of the RRAM devices with the lowest operation voltage (<1.5 V), the highest ON/OFF ratio (>10(4)), the narrowest resistance distribution, the longest retention time (>10(4) s) and the most endurance cycles (>150).

14.Modeling and Simulation of Energy Control Strategies in AC Microgrid

Author:Wen, HQ;Yang, RZ


Abstract:Microgrid is an intelligent power system wh ich contains distributed generations, energy storages, local loads, monitoring and protecting units to realize autonomous control, protect and manage functions. It's regarded as the trend for the future power system since it satisfies the rapidly-developing electrical power demand and reduces environmental concerns. Considering different operation modes of Microgrid such as grid-connected and stand-alone, the control strategies need be automatically adjusted with support from Grid, battery or Fuel Cells. In this paper, a Microgrid is buHt and simulated in PSCAD, including PV, wind power, Fuel Cell, lead acid battery, and microturbine. Both component and system level models are verified tor different scenarios with appropriate control strategies. Main results are illustrated in order to show the efTectiveness of the control strategy tor different modes.

15.A Novel Hybrid ACO/SA Approach to Solve Stochastic Dynamic Facility Layout Problem (SDFLP)

Author:Lee, TS;Moslemipour, G;Ting, TO;Rilling, D


Abstract:This paper proposes a new hybrid algorithm using ant colony optimization and simulated annealing intelligent approaches to solve a stochastic dynamic facility layout problem in which product demands are normally distributed random variables with known probability density function that changes from period to period in a random manner. Finally, the performance of the proposed algorithm is compared with the simulated annealing and another approach using data taken from the literature.

16.Partitioning Method of Virtual Microgrid Based on Electrical Coupling Strength

Author:Wu Chunchao;Xue Fei;Xu Xiaotong;Lu Shaofeng;Jiang Lin;Li Gang

Source:Automation of Electric Power Systems,2019,Vol.43

Abstract:With the fast development in the research of smart grid and Energy Internet, more and more distributed renewable energy and energy storage devices are connected into distribution networks, intelligent development of distribution network has become an inevitable trend. It is a big challenge for large-scale conventional distribution networks to be consistent with the requirements of free, equal and flexible interaction. Virtual microgrids with high internal convergence are proposed based on electrical coupling strength, which is partitioned from conventional power distribution networks. Furthermore, an implementation framework of virtual microgrids based on extended cyber, physical and socioeconomic is put forward, three-stage research problems of boundary division, resource optimization deployment and collaborative capability management are introduced. According to the first problem, by defining the electrical coupling strength, the classical Newman fast partitioning algorithm is upgraded in complicated network to realize the automatic optimization of boundary in virtual microgrids. Through case studies, the proposed algorithm is verified to be reasonable and efficient.

17.Facile preparation of Co3O4 nanoparticles incorporating with highly conductive MXene nanosheets as high-performance anodes for lithium-ion batteries

Author:Zhao, YC;Liu, CG;Yi, RW;Li, ZQ;Chen, YB;Li, YQ;Mitrovic, I;Taylor, S;Chalker, P;Yang, L;Zhao, CZ


Abstract:There is considerable scientific interest in the newly available family of MXenes material. An analog as graphene, this two-dimensional (2D) layered material with the structure of transition metal carbides or nitrides exhibits superior electronic conductivity, large interlayer spacing for highly efficient lithium ions diffusion pathways and environmental benignity, making it useful as energy storage material. However, the inferior capability to store lithium ions impedes its wide application in lithium-ion batteries. Therefore, a facile strategy for preparing Co3O4 nanoparticles incorporated with MXene nanosheets on Ni foams has been developed. Small-size Co3O4 nanoparticles are uniformly distributed within the MXene nanosheets leading to the highly efficient lithium ions and electrons transmission, as well as the prevention for the restacking of MXene nanosheets and huge volume change of the Co3O4 nanoparticles. Under the cooperative effect of Co3O4 nanoparticles and MXene nanosheets, the Co3O4/MXene composite electrode with the mass ratio of Co3O4/MXene = 1:1 exhibits an excellent reversible capacity of 1005 mAh g(-1) after 300 cycles at the current density of 1 C, which significantly exceeds that of pristine Co3O4 electrode. Though the current density climbs to 5 C, the composite electrode remains a stable capacity of 307 mAh g(-1) after 1000 cycles. It is demonstrated that Co3O4/MXene composite electrode has the potential as an anode for the high-performance lithium-ion batteries. (c) 2020 Elsevier Ltd. All rights reserved.

18.Multi-GHz Microstrip Transmission Lines Realised by Screen Printing on Flexible Substrates

Author:Shi, YZ;Jiang, ZZ;Lam, S;Leach, M;Wang, JC;Lim, EG


Abstract:This paper reports experimental work on 50 SI microstrip transmission lines implemented by screen-printing low-cost silver paste onto thin flexible polyethylene terephthalate (PET) substrates of varying thickness. The microstrip line designs are based on PET substrates with thicknesses of 1.4 mm, 0.7 mm and 0.5 mm, leading to conductive track widths of 3.8 mm, 1.7 mm and 1.2 mm respectively for a 50 SI line; these designs were then realised. The S-parameter measurements show that the insertion loss of the microstrip transmission lines on each substrate can be as low as 0.2 dB/cm, 0.17 dB/cm, and 0.14 dB/cm up to a frequency of 5 GHz in spite of the average quality of the silver paste used. The experimental results also show that the screen-printed transmission lines still work quite well in bent condition and wearable electronics application at GHz is possible.

19.Optimization for Train Speed Trajectory Based on Pontryagin's Maximum Principle

Author:Bao, K;Lu, SF;Xue, E;Tan, ZX


Abstract:Among different energy efficiency improvement technologies for railway transportation, the optimization of speed trajectory is a feasible method with low cost, since there is no need to upgrade the railway infrastructures. This paper proposes a simplified method to find speed trajectory and co-state variables. The method is based on Pontryagin's Maximum Principle (PMP) to minimize tractive energy. Hamiltonian and co-state equation are derived. The design of this paper is based on an ideal model which has no speed limit, gradient, and regenerative braking. Under the necessary condition of PMP, it can obtain acceleration, cruising, coasting, deceleration sections independently using a linear iteration, and then connect them to form full trajectory using the Linking Principle proposed in this paper. The train parameters are determined based on locomotive SS4. The results show that PMP can be applied on optimal train trajectory with minimum energy consumption.


Author:Man, KL;Chen, C;Ting, TO;Krilavicius, T;Chang, J;Poon, SH


Abstract:One of the most important and indispensable parameters of a Battery Management Systems (BMS) is accurate estimates of the State of Charge (SoC) of the battery. It can prevent battery from damage or premature aging by avoiding over charge/discharge. Due to the limited capacity of a battery, advanced methods must be used to estimate precisely the SoC in order to keep battery safely being charged and discharged at a suitable level and to prolong its life cycle. In this paper, we review several effective approaches: Coulomb counting, Open Circuit Voltage (OCV) and Kalman Filter method for performing the SoC estimation; then we propose Artificial Intelligence (AI) approach that can be efficiently used to precisely determine the SoC estimation for the smart battery management system as presented in [1]. By using our proposed approach, a more accurate SoC measurement will be obtained for the smart battery management system.
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