Effect of Negative Valve Overlap on Combustion and Emissions of CNG-Fueled HCCI Engine with Hydrogen Addition
作者：
Li, Yuelin;Zhang, Zihan;Liu, Zhiqiang* ;Tong, Peng;Yang, Dezhi;...
期刊：
International Journal of Aerospace Engineering ,2021年2021 ISSN：1687-5966
通讯作者：
Liu, Zhiqiang
作者机构：
[Li, Yuelin; Tong, Peng; Zhang, Zihan; Zhang, Wulong; Yang, Dezhi; Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.;[Zhang, Zihan] Yichun Vocat Tech Coll, Yichun 336000, Peoples R China.;[Tong, Peng] Loudi Vocat & Tech Coll, Loudi 417000, Peoples R China.
通讯机构：
[Liu, Zhiqiang] C;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.
摘要：
In order to study the effect of negative valve overlap on combustion and emission characteristics of a homogeneous charge compression ignition engine fueled with natural gas and hydrogen, the test and the simulation were conducted using an engine cycle model coupling the chemical kinetic reaction mechanism under different valve timing conditions. Results show that the internal EGR formed by using negative valve overlap could heat the inlet mixtures and improve the spontaneous ignition characteristic of the engine. The residual exhaust gas could slow down the heat release rate, decrease the pressure rise rate and the maximum combustion temperature, and reduce the NOx emission simultaneously. Among the three NVO schemes, the strategy of changing the intake valve opening timing individually can create the least power loss, and the symmetric NVO strategy which changes both the exhaust valve closing timing and the intake valve opening timing simultaneously can achieve the best heating effect of inlet mixtures and the satisfactory decrease of combustion temperature, as well as the largest reduction of NOx emission. © 2021 Yuelin Li et al.
语种：
英文
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A realistic skeletal mechanism for the oxidation of biodiesel surrogate composed of long carbon chain and polyunsaturated compounds
作者：
Wu, Gang;Wang, Xin;Abubakar, Shitu;Li, Yuqiang* ;Liu, Zhiqiang*
期刊：
Fuel ,2021年289:119934 ISSN：0016-2361
通讯作者：
Liu, Zhiqiang;Li, Yuqiang
作者机构：
[Wang, Xin; Wu, Gang; Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.;[Abubakar, Shitu] Cent South Univ, Coll Mech & Elect Engn, Changsha 410083, Peoples R China.;[Li, Yuqiang] Cent South Univ, Sch Energy Sci & Engn, Changsha 410083, Peoples R China.
通讯机构：
[Liu, Zhiqiang; Li, Yuqiang] C;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.;Cent South Univ, Sch Energy Sci & Engn, Changsha 410083, Peoples R China.
关键词：
Core sub;Ester group;Fuel;Heavy methyl esters;Mechanism;Polyunsaturated degree;Real biodiesel;Related sub
摘要：
To obtain a realistic reduced reaction model for the combustion of biodiesel in compression ignition engine, the heavy methyl esters with long carbon chain and polyunsaturated degree were used to characterize real biodiesel fuel in this study. Methyl palmitate (MHD), methyl stearate (MOD), methyl linoleate (MOD9D12D), methyl–5–decenoate (MD5D) and n–decane were selected as the surrogate of biodiesel. A skeletal mechanism with 187 species and 982 reactions was developed for the oxidation of biodiesel surrogate using the decoupling methodology. The mechanism was partitioned into three, including the relatively simplified fuel–related sub-mechanism, the ester group–related sub–mechanism, and the detailed core sub–mechanism during the construction process. It was validated by zero–dimensional ignition delay for each component in biodiesel surrogate under variable conditions. The predicted outcomes are in concordance with the experimental information, which preliminarily verifies the effectiveness and accuracy of the mechanism. A three–dimensional computational fluid dynamics code coupled with the mechanism was subsequently utilized to simulate engine combustion. The findings show that the combustion characteristics of biodiesel are robustly replicated, portraying that the newly developed biodiesel mechanism can be assuredly used in the practical engine simulation. © 2020 Elsevier Ltd
语种：
英文
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Intelligent prediction on air intake flow of spark ignition engine by a chaos radial basis function neural network
作者：
Li, Yue-lin;Liu, Bo-fu;Wu, Gang* ;Liu, Zhi-qiang;Ding, Jing-feng;...
期刊：
中南大学学报(英文版) ,2020年27(9):2687-2695 ISSN：2095-2899
通讯作者：
Wu, Gang
作者机构：
[Li, Yue-lin; Liu, Bo-fu; Liu, Zhi-qiang; Ding, Jing-feng; Wu, Gang] Key Lab Safety & Design & Reliabil Technol Engn V, Changsha 410114, Peoples R China.;[Li, Yue-lin; Liu, Zhi-qiang; Ding, Jing-feng; Wu, Gang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.;[Abubakar, Shitu] Cent South Univ, Coll Mech & Elect Engn, Changsha 410083, Peoples R China.
通讯机构：
[Wu, Gang] K;[Wu, Gang] C;Key Lab Safety & Design & Reliabil Technol Engn V, Changsha 410114, Peoples R China.;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.
关键词：
intake air flow;spark ignition engine;chaos;RBF neural network
摘要：
To ensure the control of the precision of air-fuel ratio (AFR) of port fuel injection (PFI) spark ignition (SI) engines, a chaos radial basis function (RBF) neural network is used to predict the air intake flow of the engine. The data of air intake flow is proved to be multidimensionally nonlinear and chaotic. The RBF neural network is used to train the reconstructed phase space of the data. The chaos algorithm is employed to optimize the weights of output layer connection and the radial basis center of Gaussian function in hidden layer. The simulation results obtained from Matlab/Simulink illustrate that the model has higher accuracy compared to the conventional RBF model. The mean absolute error and the mean relative error of the chaos RBF model can reach 0.0017 and 0.48, respectively.
语种：
英文
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路面附着系数的自适应衰减卡尔曼滤波估计
作者：
刘志强;刘逸群
期刊：
中国公路学报 ,2020年33(7):176-185 ISSN：1001-7372
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙 410114
关键词：
汽车工程;路面附着系数;联合仿真;自适应衰减无迹卡尔曼滤波;分布式驱动电动汽车
摘要：
为了获得实时、准确的路面附着系数,进一步提高观测路面附着系数算法的精度和收敛速度,结合非线性车辆动力学模型和轮胎力修正模型,搭建分布式驱动电动汽车联合仿真平台,提出一种基于自适应衰减无迹卡尔曼滤波的路面附着系数观测算法。该算法设计与各轮对应的路面附着系数观测器,应用协方差匹配判据对观测器发散趋势进行判别,设计自适应加权系数修正预测协方差,以增强新近观测数据的利用率;同时采用次优Sage-Husa噪声估计器对未知的系统过程噪声进行估计,抑制观测器的记忆存储长度,调整过程噪声和测量噪声的均值与协方差,提高观测器的跟踪能力。利用分布式驱动电动汽车分别进行高、低附着路面和对开路面直线制动试验,并将自适应衰减无迹卡尔曼滤波路面附着系数观测器的观测结果与无迹卡尔曼滤波观测值、参考路面附着系数进行比较和分析。结果表明:高附着路面条件下,所设计的算法估计误差可控制在0.64%以内;低附着路面条件下,所设计的算法估计误差可控制在1.03%以内;对开路面条件下估计误差可控制在1.26%以内;自适应衰减无迹卡尔曼滤波算法相比无迹卡尔曼滤波算法响应速率更快,具有更高的估计精度和较强的自适应能力,估计结果整体上维持稳定,能够适应各种不同路面的估计。
语种：
中文
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Simulation and experiments of active vibration control for ultra-long flexible manipulator under impact loads:
作者：
Huang, Yi* ;Liu, Zhiqiang;Du, Ronghua;Tang, Hongbin
期刊：
Journal of Vibration and Control ,2019年25(3):675-684 ISSN：1077-5463
通讯作者：
Huang, Yi
作者机构：
[Du, Ronghua; Huang, Yi; Liu, Zhiqiang; Tang, Hongbin] Changsha Univ Sci & Technol, Sch Automot & Mech Engn, Changsha, Hunan, Peoples R China.;[Huang, Yi] Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha, Hunan, Peoples R China.;[Huang, Yi] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha, Hunan, Peoples R China.;[Huang, Yi] Changsha Univ Sci & Technol, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Huang, Yi] C;Changsha Univ Sci & Technol, Changsha 410114, Hunan, Peoples R China.
关键词：
Active vibration control;frequency domain;least mean square method;flexible manipulator;fast Fourier transform;inverse fast Fourier transform;pump truck
摘要：
This paper aims to reduce the tip vibration of an ultra-long flexible manipulator subjected to impact loads. A modified least mean square method is proposed to determine the frequency response matrix of control paths and identify the complex amplitude of external excitation responses. The presented work is innovative in the sense that: (1) a theoretical model and a new algorithm are proposed for the identification of explicit convergence conditions of online parameters, and they are used to calculate output variables for the optimized robotic control; (2) an active numerical approach is developed to control the response of the tip vibration of the manipulator. The control algorithm is based on a relational model of control parameters and system outcomes; (3) design of experiments is performed for the verification purpose. The active vibration control has been demonstrated on a pump truck product where the third boom hydraulic cylinder is selected as the actuator for testing, and the manipulator tip is equipped with an acceleration sensor to collect the information of vibration; and (4) the performance of the proposed active vibration control has been validated on the flexible manipulator, and the results have shown that the amplitude of the vibration of robotic tip has been decreased for more than 60%.
语种：
英文
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分布式驱动电动汽车稳定性控制仿真与试验
作者：
刘志强;刘广
期刊：
汽车工程 ,2019年41(7):792-799 ISSN：1000-680X
通讯作者：
Liu, Z.
作者机构：
长沙理工大学汽车与机械工程学院,长沙,410114;[刘志强; 刘广] 长沙理工大学
通讯机构：
School of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha, China
关键词：
分布式驱动电动汽车;可拓控制;滑模控制;联合仿真;实车试验
摘要：
为提高电动汽车的操纵稳定性,建立了3层的控制策略。动力学建模层计算变量实际值和期望值;补偿力矩确定层结合可拓控制与滑模控制的优势,建立自适应滑模算法,协调各参数控制的权重并确定合适的补偿力矩;车轮转矩分配层对补偿力矩提供约束后将其分配给4个轮毂电机。采用Carsim和Simulink软件进行模型搭建和联合仿真。仿真结果表明,整车控制策略的实时性和自适应性好。最后,在样车上进行快速原型试验也验证了所采用的控制策略达到了改善车辆稳定性的预期目标。
语种：
中文
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四轮毂驱动EV双容积卡尔曼路面附着系数估计
作者：
刘志强;刘逸群
期刊：
长沙理工大学学报(自然科学版) ,2019年16(03):55-62 ISSN：1672-9331
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙,410114;[刘志强; 刘逸群] 长沙理工大学
关键词：
电动汽车;轮毂驱动;仿真;路面附着系数;容积卡尔曼滤波;双容积卡尔曼滤波
摘要：
针对车辆在行驶过程中难以实时、准确地获取路面附着系数这一问题,本研究在结合车辆三自由度动力学模型和Dugoff修正轮胎力模型所搭建的四毂驱动联合仿真电动汽车平台基础上,设计了一种时效性、鲁棒性强的双容积卡尔曼滤波路面附着系数观测算法。双容积卡尔曼滤波算法利用奇异值分解优化求解误差协方差矩阵,将车辆行驶状态观测器信息与附着系数观测器信息相互联系,形成闭环反馈校正更新观测信号,实现对路面附着系数的实时估计。在四轮毂驱动联合仿真电动汽车平台中设置低附着路面,在开路面仿真工况下对双容积卡尔曼滤波算法进行验证,并与传统容积卡尔曼滤波观测器数据进行比较和分析。结果表明:双容积卡尔曼滤波算法具有更快的的响应速度,估计的路面附着系数精度更高,实时性更强。
语种：
中文
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Prediction of the performance and emissions of a spark ignition engine fueled with butanol-gasoline blends based on support vector regression
作者：
Zuo, Qingsong;Zhu, Xinning;Liu, Zhiqiang* ;Zhang, Jianping;Wu, Gang;...
期刊：
ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY ,2019年38(3):- MAY-JUN ISSN：1944-7442
通讯作者：
Liu, Zhiqiang
作者机构：
[Zuo, Qingsong; Zhang, Jianping; Zhu, Xinning] Xiangtan Univ, Coll Mech Engn, Xiangtan 411100, Hunan, Peoples R China.;[Li, Yuelin; Wu, Gang; Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 411100, Hunan, Peoples R China.
通讯机构：
[Liu, Zhiqiang] C;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 411100, Hunan, Peoples R China.
关键词：
butanol;alternative fuel;support vector regression;SI engine
摘要：
Butanol is considered as the more promising alternative fuel candidate because of its favorable chemical and physical properties over ethanol and methanol. In this study, the performance and emissions of a port fuel injected spark ignition engine fueled with butanol-gasoline blends (0–60 vol % butanol blended with gasoline referred as G100-B60), including brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and carbon monoxide (CO), unburned hydrocarbon (UHC), nitrogen oxide (NO x ), were investigated under various equivalence ratio. Among the butanol-gasoline blends, B30 performs well in engine performance and emissions due to its CO (2.3%–8.7%), UHC (12.4%–27.5%), and NO x (2.8%–19.6%) emissions compared to those of gasoline. Butanol can be a good alternative fuel to gasoline for its potential to reduce pollutant emissions. It is well known that engine tests are hard, time consuming, and high cost. Therefore, support vector regression (SVR) was used to predict the performance and emissions of the engine, where equivalence ratio and blend ratio were used as the input parameters, and BTE, BSFC, CO, UHC, and NO x were used as the output parameters. It was observed that the correlation coefficients and mean relative error were in the range of 0.9940–0.9998 and 0.1901–10.2570%, respectively. The SVR predictions of BTE, BSFC, CO, UHC, and NO x yielded the root-mean-squared-errors of 0.0511%, 4.6058 g/kW h, 0.9995% vol, 7.7503 ppm vol and 38.5861 ppm, respectively. It could be indicated that the SVR provided an accurate and simple approach to analyze performance and exhaust emissions of spark ignition engine. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13042, 2019. © 2018 American Institute of Chemical Engineers
语种：
英文
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混合动力电动汽车无级变速-动力耦合机构
作者：
刘志强;马源晖;向青青
期刊：
长沙理工大学学报(自然科学版) ,2018年15(4):80-86 ISSN：1672-9331
作者机构：
长沙理工大学汽车与机械工程学院,湖南长沙,410114;[马源晖; 刘志强; 向青青] 长沙理工大学
关键词：
动力耦合机构;五杆星系轮系;混合动力电动汽车;无级变速;传动比;能流图;仿真
摘要：
为提高混合动力电动汽车燃油经济性,设计了一种五杆行星轮系动力耦合机构。该机构利用双行星排实现三动力耦合,其中,发动机与行星架相连,电机1通过链轮1和太阳轮1相连,电机2和太阳轮2相连,并通过链轮2把动力传到驱动桥。推导了输出轴转速与三个动力源转速的关系,传动比分析表明,该机构在实现动力耦合的同时,还能在运行过程中无级变速。对启动、起步、加速和上坡、巡航、滑行、刹车制动、低速纯电动和倒车等8种运行工况进行了能量流动路径分析,采用Advisor软件在某车型上对耦合机构进行了新欧洲行驶工况仿真验证。研究结果表明,回收的制动能量增加了45 kJ,回收率提高了3.42%,有效地提高了整车燃油经济性。
语种：
中文
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Effect of extended necks on transmission loss performances of Helmholtz resonators in presence of a grazing flow
作者：
Zhao, He;Lu, Zhengli;Guan, Yiheng;Liu, Zhiqiang* ;Li, Guoneng;...
期刊：
Aerospace Science and Technology ,2018年77:228-234 ISSN：1270-9638
通讯作者：
Ji, C. Z.;Liu, Zhiqiang
作者机构：
[Ji, C. Z.; Zhao, He; Lu, Zhengli; Guan, Yiheng] Jiangsu Univ Sci & Technol, Sch Energy & Power Engn, Mengxi Rd 2, Zhenjiang City 212003, Jiangsu, Peoples R China.;[Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Li, Guoneng] Zhejiang Univ Sci & Technol, Sch Mech & Automot Engn, Liuhe Rd, Hangzhou 310023, Zhejiang, Peoples R China.;[Liu, Jun] Jiangsu Jintongling Fluid Machinery Technol Co Lt, 135 Mid Zhongxiu Rd, Nantong City 226001, Jiangsu, Peoples R China.;[Ji, C. Z.] Nanyang Technol Univ, Coll Engn, Singapore 639798, Singapore.
通讯机构：
[Ji, C. Z.] J;[Liu, Zhiqiang] C;Jiangsu Univ Sci & Technol, Sch Energy & Power Engn, Mengxi Rd 2, Zhenjiang City 212003, Jiangsu, Peoples R China.;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Acoustic damper;Grazing flow;Helmholtz resonator;Noise damping;Transmission loss
摘要：
Suppressing acoustic pulsations is a critical task in modern premixed combustion-involved gas turbines. As a classical acoustic noise damper, Helmholtz resonator is generally applied in gas turbine combustors to reduce the transmission of acoustic perturbations. However, the neck configuration of a Helmholtz resonator may be designed in different ways. To obtain an optimum design and to compare the noise damping performances of these different configurations of the resonator necks, comparison study is conducted via developing a 2D linearized Navier–Stokes model of a duct in the presence of a grazing flow. A Helmholtz resonator is implemented on the duct as a side branch. The model is in frequency domain and it is validated first by comparing the numerical results with the experimental measurements available in the literature. The effects of 1) 3 extended neck configurations, 2) extended neck length and 3) the grazing flow Mach number are evaluated. It is shown that higher Mach number of the grazing flow, lower transmission loss. As the extended neck is in different configurations, the resonant frequencies and the maximum transmission losses are dramatically different, especially as the grazing Mach number Mu is greater than 0.05, i.e. Mu≥0.05. Approximately 20% resonant frequency shift is observed. The conventional design of Helmholtz resonator without an extended neck is found to perform much less effective than that of with concentric extended neck. The optimum design of the resonator neck can lead to 5–11 dB more transmission loss over a broader frequency range, especially at higher Mach number. The noise damping mechanism is visualized by the formation of vortex shedding at the neck of the resonator and sound energy is converted into kinetic energy being dissipated by the surrounding air. The present work opens up a predictive means to optimize the design of a Helmholtz resonator. © 2018 Elsevier Masson SAS
语种：
英文
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An artificial neural network developed for predicting of performance and emissions of a spark ignition engine fueled with butanol–gasoline blends
作者：
Liu, Zhiqiang;Zuo, Qingsong* ;Wu, Gang;Li, Yuelin
期刊：
Advances in Mechanical Engineering ,2018年10(1) ISSN：1687-8132
通讯作者：
Zuo, Qingsong
作者机构：
[Li, Yuelin; Wu, Gang; Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha, Hunan, Peoples R China.;[Zuo, Qingsong] Xiangtan Univ, Sch Mech Engn, Xiangtan 411105, Peoples R China.
通讯机构：
[Zuo, Qingsong] X;Xiangtan Univ, Sch Mech Engn, Xiangtan 411105, Peoples R China.
关键词：
Butanol;performance;emissions;alternative fuels;spark ignition engine
摘要：
The engine experiments require multiple tests that are hard, time-consuming, and high cost. Therefore, an artificial neural network model was developed in this study to successfully predict the engine performance and exhaust emissions when a port fuel injection spark ignition engine fueled with n-butanol–gasoline blends (0–60 vol.% n-butanol blended with gasoline referred as G100-B60) under various equivalence ratio. In the artificial neural network model, compression ratio, equivalence ratio, blend percentage, and engine load were used as the input parameters, while engine performance and emissions like brake thermal efficiency, brake-specific fuel consumption, carbon monoxide, unburned hydrocarbons, and nitrogen oxides were used as the output parameters. In comparison between experimental data and predicted results, a correlation coefficient ranging from 0.9929 to 0.9996 and a mean relative error ranging from 0.1943% to 9.9528% were obtained. It is indicated that the developed artificial neural network model was capable of predicting the combustion of n-butanol–gasoline blends due to a commendable accuracy. © 2018, © The Author(s) 2018.
语种：
英文
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Destination unaware geometric routing for delay tolerant networks
作者：
Liu, Zhi Qiang;Wang, Tong;Wang, Xi Bo
期刊：
International Journal of Security and Networks ,2017年12(2):103-111 ISSN：1747-8405
通讯作者：
Wang, Tong(wangtong@hrbeu.edu.cn)
作者机构：
[Liu, Zhi Qiang] College of Automotive and Mechanical, Changsha University of Science and Technology, Changsha, 410076, China;[Wang, Xi Bo; Wang, Tong] College of Information and Communication Engineering, Harbin Engineering University, Harbin, 150001, China
通讯机构：
College of Information and Communication Engineering, Harbin Engineering University, Harbin, China
关键词：
routing protocol;geometric routing.
摘要：
Receiving great interest from the research community, the concept of delay/disruption tolerant networks (DTNs) is without the contemporaneous end to end connectivity to bridge communication in the challenged networks, suffering from sparse network density and frequent disruption. In this paper, our motivation is to firstly adopt geographic information instead of history encounter information to relay message. Then we argue it is unreasonable to rely on realtime location of destination to relay message due to sparse network density and high mobility. Therefore, our contribution is to propose a geographic routing algorithm for DTNs without knowing where the destination is. The key insight is to replicate message in an efficient manner rather than flooding, taking into account encounter angle between pairwise nodes. Evaluation results under the Helsinki city scenario show an improvement of our proposed.
语种：
英文
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基于模糊控制的纯电动汽车再生制动策略仿真
作者：
卢珊;刘志强;葛进;叶青
期刊：
长沙理工大学学报(自然科学版) ,2017年14(3):90-96 ISSN：1672-9331
作者机构：
长沙理工大学汽车与机械工程学院,湖南长沙,410004;[葛进; 卢珊; 刘志强; 叶青] 长沙理工大学
关键词：
纯电动汽车;ECE法规线;制动能量回馈效率;模糊控制系统;续航里程
摘要：
为了使纯电动汽车在制动时既能保证安全性,又能获取最大的制动能量回馈效率,综合考虑了ECE法规线、I曲线、f线以及M线对制动力分配的规范作用,结合模糊控制算法,提出了一种以车速v、制动强度z以及蓄电池SOC三者为输入、制动能量回馈比例Kr为输出的模糊控制系统.在此基础上建立了再生制动模型,将其嵌入到ADVISOR 2002中,并在CYC_UDDS工况下进行仿真.研究结果表明,新的再生制动策略比ADVISOR 2002原有的控制方案回收率提高了6.36％,显著提高了电动汽车的实际续航里程.
语种：
中文
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变电站三维智能虚拟运检系统
作者：
王会勤;周育才;左萃;刘志强
期刊：
电力科学与技术学报 ,2017年32(4):73-78 ISSN：1673-9140
作者机构：
[王会勤] 浙江浙能温州发电有限公司;长沙理工大学能源与动力工程学院;[左萃] 湖南生物机电职业技术学院;长沙理工大学汽车与机电工程学院;[周育才; 刘志强] 长沙理工大学
关键词：
变电站;虚拟现实;智能运检系统;三维建模
摘要：
设计变电站三维智能虚拟运检系统结构和具体制作方案.首先,介绍层次细节和点云计算三维建模的关键技术,利用Multi Gen Creator三维建模软件和虚拟开发平台进行三维模型建模;然后,建立用户交互界面和数据库,构建变电站三维智能运检系统;最后,以安徽阜阳500 kV变电站新建工程为例进行测试,测试结果表明:该系统能够直观展示每个设备的属性信息、位置坐标和信息数据,能够模拟生产操作和调取实时监控画面,为变电站的生产管理和运营决策提供可视化平台支持,提升了管理效率和变电站的智能化水平.
语种：
中文
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Brushless DC Motor Torque Estimation Based on Nonlinear Partial Least Square Method
作者：
张志勇;张飞;刘志强;张新
期刊：
电工技术学报 ,2017年32(5):62-69 ISSN：1000-6753
通讯作者：
Zhang, Zhiyong(zzy04@163.com)
作者机构：
[张志勇] Engineering Research Center of Catastrophic Prophylaxis and Treatment of Road &, Traffic Safety, Ministry of Education, Changsha, 410114, China;[张飞; 刘志强; 张新] College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha, 410114, China;[张志勇; 张飞] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle Hunan Province, Changsha, 410114, China
通讯机构：
[Zhang, Z.] E;Engineering Research Center of Catastrophic Prophylaxis and Treatment of Road & Traffic Safety, Ministry of Education, Changsha, China
关键词：
无刷直流电机;转矩估计;直接转矩控制;非线性偏最小二乘
摘要：
针对无刷直流电机直接转矩控制系统中,电机输出转矩估计或观测存在需检测电机状态信号难以精确地检测、观测或计算等不可避免的难题,提出一种利用电机线电流和转速两个易检测信号进行电机输出转矩估计的方法。该方法首先基于拉丁超立方抽样方法确定建模数据,确保离散数据的可靠性;然后通过核函数将建模数据中的自变量变换到特征空间,将自变量与因变量之间的非线性关系在特征空间中线性地展开;最后在特征空间中利用偏最小二乘回归方法建立电机输出转矩的估计模型。通过对转矩估计精度和控制系统性能进行分析及实验验证,证明了所提转矩估计方法能准确地估计电机输出转矩,确保电机直接转矩控制系统的性能,该方法具有较强的实用性。
语种：
中文
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Fuzzy control method of regenerative braking in electric vehicles considering parameter sensitivity
作者：
刘志强;汪浩磊;杜荣华
期刊：
中南大学学报(自然科学版) ,2016年47(11):3700-3706 ISSN：1672-7207
通讯作者：
Liu, Zhiqiang(lzq0228@126.com)
作者机构：
[汪浩磊; 杜荣华; 刘志强] School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha, 410114, China
通讯机构：
School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha, China
关键词：
电动汽车;制动力分配;模糊控制;灵敏度分析
摘要：
分析影响电动汽车制动能量回馈的主要因素;以制动能量最大化为目标,建立电液复合制动力分配模型,设计以电液复合制动特性参数蓄电池荷电状态(S_(OC))、制动强度、车速为输入,回馈制动比例为输出的制动力模糊分配规则。同时,以能量回收率为评价指标对S_(OC)、制动强度及车速进行灵敏度分析。研究结果明:S_(OC)对能量回收率的影响最大,制动强度对能量回收率的影响次之;根据各特性参数对评价指标的影响权重,可改进电液复合制动力分配模糊规则;在相同制动工况下,考虑参数灵敏度的电动汽车电液复合回馈制动模糊控制方法可有效提高制动能量回收率。
语种：
中文
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无刷直流外转子电机结构参数优化
作者：
刘志强;舒刚华;杜荣华;杨中华
期刊：
食品与机械 ,2016年32(11):93-97,228 ISSN：1003-5788
作者机构：
长沙理工大学汽车与机械工程学院, 湖南, 长沙, 410114;长沙中成汽车零部件有限公司技术部, 湖南, 长沙, 410114;[刘志强; 舒刚华; 杜荣华] 长沙理工大学汽车与机械工程学院, 湖南, 长沙, 410114;[杨中华] 长沙中成汽车零部件有限公司技术部, 湖南, 长沙, 410114
关键词：
优化设计;Taguchi方法;齿槽转矩;直流外转子电机;有限元分析
摘要：
齿槽转矩脉动是影响直流外转子电机输出转矩脉动的主要原因。为抑制齿槽转矩脉动,根据电机的结构参数建立了有限元分析模型,并对齿槽转矩进行仿真;仿真结果与试验获取的齿槽转矩曲线吻合较好,证明了所建模型的正确性。然后,采用Taguchi方法,以齿槽转矩峰值和平均输出转矩作为优化目标,以槽口宽度、极弧系数、气隙长度、平行齿宽为控制因子,选取槽口宽度加工误差、气隙长度加工误差、平行齿宽加工误差和永磁体剩磁变化作为噪声因子,对电机进行了优化设计,并利用所建立的有限元分析模型进行性能仿真验证。结果表明:用Taguchi方法优化电机设计参数,能够在电机平均输出转矩略有增加的同时,显著降低齿槽转矩。
语种：
中文
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纯电动汽车电液制动力分配计算方法
作者：
刘志强;刘周博涵
期刊：
公路与汽运 ,2016年(4):4-7 ISSN：1671-2668
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙,410004;[刘志强; 刘周博涵] 长沙理工大学
关键词：
汽车;电动汽车;电液制动;计算流程;可回收能量比
摘要：
基于汽车制动力学，建立了纯电动汽车电液制动力分配数学模型；结合 ECE R13- H制动法规，确定了汽车的制动力安全分配范围，在该允许范围内，制定了尽量提高能量回收效率的制动力分配流程，驱动轴的制动需求尽量利用电机制动，不足部分通过调整液压制动力补充；并以15°/s 匀速旋转制动踏板和以5°/s2匀加速转动制动踏板二种工况为例，阐明了电-液制动力的分配计算流程，得到了较高的可回收能量比，验证了数学模型的合理性与分配策略的有效性。
语种：
中文
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独立学院机制专业学生实践能力培养机制研究
作者：
何志勇;陈耿彪;杜荣华;刘志强
期刊：
教育教学论坛 ,2016年(34):165-167 ISSN：1674-9324
作者机构：
长沙理工大学汽车与机械工程学院,湖南 长沙,410114;[何志勇; 陈耿彪; 杜荣华; 刘志强] 长沙理工大学
关键词：
独立学院;机制专业;实践能力;教学改革
摘要：
文章针对独立学院的办学目的，分析了目前人才培养的不足，以长沙理工大学独立学院机制专业的高级应用型人才培养为例，从培养方案、课程体系设置、实践教学平台的建立、师资队伍建设、校企合作模式等方面进行综合改革，形成了鲜明的办学特色，取得了良好的教学效果。
语种：
中文
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纯电动汽车电液复合回馈制动研究
作者：
刘志强;汪浩磊;杜荣华;杨中华
期刊：
汽车工程 ,2016年38(8):955-960 ISSN：1000-680X
作者机构：
[汪浩磊; 杜荣华; 刘志强] School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha, 410114, China;[杨中华] Changsha Zhongcheng Automotive Components Co., Ltd., Changsha, 410114, China
关键词：
电动汽车;电液复合回馈制动;模糊控制
摘要：
通过对电动汽车制动能量回馈约束条件的分析,制定了一种基于制动能量回收最大化的电液复合制动力协调式控制策略。设计了以车速、制动强度、蓄电池SOC为输入,回馈制动比例为输出的电液复合制动力模糊分配控制器,建立了电液复合制动力分配模型,并进行了仿真分析。同时,设计了一种缩小比例的电液复合回馈制动模拟实验台,进行模拟实验,通过仿真分析和模拟实验,验证了该策略的可行性。
语种：
中文
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