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New Family of Exact Solutions and Chaotic Soltions of Generalized Breor-Kaup System in (2+1)-Dimensions via an Extended Mapping Approach 被引量:11
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作者 FANG Jian-Ping ZHENG Chun-Long +2 位作者 ZHU Hai-Ping REN Qing-Bao CHEN Li-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期203-208,共6页
Starting from an extended mapping approach, a new type of variable separation solution with arbitrary functions of generalized (2+1)-dimensional Broer-Kaup system (GBK) system is derived. Then based on the derived sol... Starting from an extended mapping approach, a new type of variable separation solution with arbitrary functions of generalized (2+1)-dimensional Broer-Kaup system (GBK) system is derived. Then based on the derived solitary wave solution, we obtain some specific chaotic solitons to the (2+1)-dimensional GBK system. 展开更多
关键词 extended mapping approach GBK system exact solution chaotic soliton
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The extended symmetry approach for studying the general Korteweg-de Vries-type equation 被引量:1
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作者 李志芳 阮航宇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期3-10,共8页
The extended symmetry approach is used to study the general Korteweg-de Vries-type (KdV-type) equation. Several variable-coefficient equations are obtained. The solutions of these resulting equations can be construc... The extended symmetry approach is used to study the general Korteweg-de Vries-type (KdV-type) equation. Several variable-coefficient equations are obtained. The solutions of these resulting equations can be constructed by the solutions of original models if their solutions are well known, such as the standard constant coefficient KdV equation and the standard compound KdV--Burgers equation, and so on. Then any one of these variable-coefficient equations can be considered as an original model to obtain new variable-coefficient equations whose solutions can also be known by means of transformation relations between solutions of the resulting new variable-coefficient equations and the original equation. 展开更多
关键词 extended symmetry approach general Korteweg-de Vries-type (KdV-type) equation variable-coefficient equation
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New Families of Exact Excitations to (2+1)-Dimensional Toda Lattice System via an Extended Projective Approach
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作者 FANG Jian-Ping FEI Jin-Xi ZHENG Chun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期864-868,共5页
In this paper, the extended projective approach, which was recently presented and successfully used in some continuous nonlinear physical systems, is generalized to nonlinear partial differential-difference systems (... In this paper, the extended projective approach, which was recently presented and successfully used in some continuous nonlinear physical systems, is generalized to nonlinear partial differential-difference systems (DDEs), As a concrete example, new families of exact solutions to the (2+1)-dimensional Toda lattice system are obtained by the extended projective approach. 展开更多
关键词 extended projective approach DDEs Toda lattice exact solution
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Explicit and Exact Solutions to N-Order Schrodinger System via an Extended Mapping Approach
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作者 ZHU Hai-Ping ZHENG Chun- Long FANG Jian-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期483-486,共4页
In this paper, we extend the mapping approach to the N-order Schrodinger equation. In terms of the extended mapping approach, new families of variable separation solutions with some arbitrary functions are derived.
关键词 extended mapping approach SchrSdinger equation exact solution
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Exact Solution to (1+1)-Dimensional Higher-Order Schrodinger Equation via an Extended Mapping Approach
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作者 ZHU Hai-Ping ZHENG Chun-Long FANG Jian-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期127-130,共4页
Starting from a special variable transformation and with the help of an extended mapping approach, the high-order Schrodinger equation (n = 3, 4) is solved. A new family of variable separation solutions with arbitra... Starting from a special variable transformation and with the help of an extended mapping approach, the high-order Schrodinger equation (n = 3, 4) is solved. A new family of variable separation solutions with arbitrary functions is derived. 展开更多
关键词 extended mapping approach Schrodinger equation exact solution
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Extended Wronskian Determinant Approach and Iterative Solutions ofOne-Dimensional Dirac Equation
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作者 XUYing LUMeng SURu-Keng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期859-866,共8页
An approximation method, namely, the Extended Wronskian Determinant Approach, is suggested to study the one-dimensional Dirac equation. An integral equation, which can be solved by iterative procedure to find the wave... An approximation method, namely, the Extended Wronskian Determinant Approach, is suggested to study the one-dimensional Dirac equation. An integral equation, which can be solved by iterative procedure to find the wave functions, is established. We employ this approach to study the one-dimensional Dirac equation with one-well potential,and give the energy levels and wave functions up to the first order iterative approximation. For double-well potential,the energy levels up to the first order approximation are given. 展开更多
关键词 extended Wronskian determinant approach iteration method double-well potential
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Exact Travelling Solutions of Discrete sine-Gordon Equation via Extended Tanh-Function Approach
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作者 DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期23-27,共5页
In this paper, we generalize the extended tanh-function approach, which was used to find new exact travelling wave solutions of nonlinear partial differential equations or coupled nonlinear partial differential equati... In this paper, we generalize the extended tanh-function approach, which was used to find new exact travelling wave solutions of nonlinear partial differential equations or coupled nonlinear partial differential equations, to nonlinear differential-difference equations. As illustration, two series of exact travelling wave solutions of the discrete sine-Gordon equation are obtained by means of the extended tanh-function approach. 展开更多
关键词 discrete sine-Gordon equation exact travelling wave solution extended tanh-function approach
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Study on (2+1)-Dimensional Nizhnik-Novikov-Veselov Equation by Using Extended Mapping Approach
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作者 XU Chang-Zhi HE Bao-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期10-14,共5页
Extended mapping approach is introduced to solve (2+1)-dimensional Nizhnik-Novikov Veselov equation. A new type of variable separation solutions is derived with arbitrary functions in the model. Based on this excit... Extended mapping approach is introduced to solve (2+1)-dimensional Nizhnik-Novikov Veselov equation. A new type of variable separation solutions is derived with arbitrary functions in the model. Based on this excitation, rich localized structures such as multi-lump soliton and ring soliton are revealed by selecting the arbitrary function appropriately. 展开更多
关键词 extended mapping approach (2+1)-dimensional Nizhnik-Novikov-Veselov equation new localized excitation
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Hybrid approach used for extended image-based wavefront sensor-less adaptive optics 被引量:6
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作者 董冰 喻际 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第4期21-25,共5页
The stochastic paralld gradient descent (SPGD) algorithm is widely used in wavefront sensor-less adaptive optics (WSAO) systems. However, the convergence is relatively slow. Modal-based algorithms usually provide ... The stochastic paralld gradient descent (SPGD) algorithm is widely used in wavefront sensor-less adaptive optics (WSAO) systems. However, the convergence is relatively slow. Modal-based algorithms usually provide much faster convergence than SPGD; however, the limited actuator stroke of the deformable mirror (DM) often prohibits the sensing of higher-order modes or renders a closed-loop correction inapplicable. Based on a comparative analysis of SPGD and the DM-modal-based algorithm, a hybrid approach involving both algorithms is proposed for extended image-based WSAO, and is demonstrated in this experiment. The hybrid approach can achieve similar correction results to pure SPGD, but with a dramatically decreased iteration number. 展开更多
关键词 DM Hybrid approach used for extended image-based wavefront sensor-less adaptive optics MODE
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Fully Actuated System Approach for 6DOF Spacecraft Control Based on Extended State Observer 被引量:5
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作者 ZHAO Qin DUAN Guang-Ren 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2022年第2期604-622,共19页
This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state... This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state-space model by variable elimination.Considering the uncertainties from external disturbance,unknown motion information,and uncertain inertia properties,an extended state observer(ESO)is designed to estimate the total disturbance.Then,a tracking controller based on FAS approach is designed,and this makes the closed-loop system a constant linear one with an arbitrarily assignable eigenstructure.The solution to the parameter matrices of the observer and controller is given subsequently.It is proved via the Lyapunov stability theory that the observer errors and tracking errors both converge into the neighborhood of the origin.Finally,numerical simulation demonstrates the effectiveness of the proposed controller. 展开更多
关键词 Constant linear closed-loop system extended state observer fully actuated system approach relative position and attitude control
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Extended endoscopic endonasal approach for pituitary adenoma: a single-center experience of 171 patients 被引量:1
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作者 Xiaobing Jiang Zhen Liu +2 位作者 Xing Huang Haijun Wang Hongyang Zhao 《Chinese Neurosurgical Journal》 CSCD 2017年第3期134-141,共8页
Background: Pituitary adenoma (PA) is a common intracranial tumor and surgical treatment is considered to be the best treatment for most patients. The extended endoscopic endonasal approach (EEEA) has been used to tre... Background: Pituitary adenoma (PA) is a common intracranial tumor and surgical treatment is considered to be the best treatment for most patients. The extended endoscopic endonasal approach (EEEA) has been used to treat increasing numbers of patients with PA in recent years. We conducted this study to evaluate the safety and efficacy of this approach for PA resection. Methods: We performed a retrospective analysis of all patients who underwent an EEEA to remove PA by a binostril, four-handed technique between October 2013 and April 2016 in our department. The medical information of the patients including gender, age, tumor size, hormone level, clinical outcome, and complications were collected and analyzed.Results: From a total of 593 pituitary adenoma surgeries, 171 patients (101 male and 70 female, mean age 47.4 ± 12.8 years) underwent EEEA, including 96 with functional adenomas (56.14%) and 75 with nonfunctional adenomas (43.86%). The most common symptoms were headache and vision change. Gross total resection was achieved in 126 patients (73.68%). Common complications were hyposmia or anosmia, diabetes insipidus, hypopituitarism, postoperative cerebrospinal fluid leak, cerebral hemorrhage, and epistaxis. The mean duration of follow-up was 14.6 months (range: 6–31 months). Conclusions: The application of EEEA for PA resection by a binostril, four-handed technique provided great surgical freedom with minimal invasion, and resulted in few complications. EEEA is a secure and effective surgical method that could be used for the majority of PAs. 展开更多
关键词 Pituitary adenoma ENDOSCOPE extend endoscopic endonasal approach
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Nucleon effective mass in symmetric nuclear matter from the extended Brueckner-Hartree-Fock approach
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作者 甘胜鑫 左维 U.Lombardo 《Chinese Physics C》 SCIE CAS CSCD 2012年第6期513-518,共6页
We have calculated the nucleon effective mass in symmetric nuclear matter within the framework of the Brueckner-Bethe-Goldstone (BBG) theory, which has been extended to include both the contributions from the ground... We have calculated the nucleon effective mass in symmetric nuclear matter within the framework of the Brueckner-Bethe-Goldstone (BBG) theory, which has been extended to include both the contributions from the ground-state correlation effect and the three-body force (TBF) rearrangement effect. The effective mass is predicted by including the ground-state correlation effect and the TBF rearrangement effect, and we discuss the momentum dependence and the density dependence of the effective mass. It is shown that the effect of ground state correlations plays an important role at low densities, while the TBF-induced rearrangement effect becomes predominant at high densities. 展开更多
关键词 nucleon effective mass extended BHF approach ground state correlations TBF rearrangementeffect
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Modelling the Roles of Cewebrity Trust and Platform Trust in Consumers’Propensity of Live-Streaming:An Extended TAM Method 被引量:8
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作者 Donghui Li Guozheng Zhang +4 位作者 Zeng Xu Yong Lan Yongdong Shi Zhiyao Liang Haiwen Chen 《Computers, Materials & Continua》 SCIE EI 2018年第4期137-150,共14页
Live streaming is a booming industry in China,involving an increasing number of Internet users.Previous studies show that trust is a cornerstone to develop ecommerce.Trust in the streaming industry is different from t... Live streaming is a booming industry in China,involving an increasing number of Internet users.Previous studies show that trust is a cornerstone to develop ecommerce.Trust in the streaming industry is different from that of other e-commerce areas.There are two major dimensions of trust in the live streaming context:platform trust and cewebrity trust,which are both important for customers to adopt and reuse a specific live streaming service.We collected questionnaire data from 520 participates who have used live streaming services in China.We model the collected data and identified factors that can influence users’propensity by an extended technology acceptance model(TAM)method.According to our analysis,both cewebrity trust and platform trust will greatly influence users’intention to reuse a certain platform.Moreover,results also indicate that cewebrity trust is far more important than platform trust.These findings can lead to several management strategies to improve the adherence of users to streaming platforms. 展开更多
关键词 Live streaming extended TAM approach consumers’propensity cewebrity trust platform trust
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Symbolic Computation of Extended Jacobian Elliptic Function Algorithm for Nonlinear Differential-Different Equations
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作者 DAIChao-Qing MENGJian-Ping ZHANGJie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期471-478,共8页
The Jacobian elliptic function expansion method for nonlinear differential-different equations and its algorithm are presented by using some relations among ten Jacobian elliptic functions and successfully construct m... The Jacobian elliptic function expansion method for nonlinear differential-different equations and its algorithm are presented by using some relations among ten Jacobian elliptic functions and successfully construct more new exact doubly-periodic solutions of the integrable discrete nonlinear Schrodinger equation. When the modulous m → 1or 0, doubly-periodic solutions degenerate to solitonic solutions including bright soliton, dark soliton, new solitons as well as trigonometric function solutions. 展开更多
关键词 integrable discrete nonlinear Schrodinger equation extended Jacobian elliptic function expansion approach doubly-periodic wave solutions solitonic solutions singly-periodic wave solutions
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Multiple rational rogue waves for higher dimensional nonlinear evolution equations via symbolic computation approach 被引量:1
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作者 Saima Arshed Nauman Raza +2 位作者 Asma Rashid Butt Ahmad Javid J.F.Gómez-Aguilar 《Journal of Ocean Engineering and Science》 SCIE 2023年第1期33-41,共9页
The paper investigates the multiple rogue wave solutions associated with the generalized Hirota-Satsuma-Ito(HSI)equation and the newly proposed extended(3+1)-dimensional Jimbo-Miwa(JM)equation with the help of a symbo... The paper investigates the multiple rogue wave solutions associated with the generalized Hirota-Satsuma-Ito(HSI)equation and the newly proposed extended(3+1)-dimensional Jimbo-Miwa(JM)equation with the help of a symbolic computation technique.By incorporating a direct variable trans-formation and utilizing Hirota’s bilinear form,multiple rogue wave structures of different orders are ob-tained for both generalized HSI and JM equation.The obtained bilinear forms of the proposed equations successfully investigate the 1st,2nd and 3rd-order rogue waves.The constructed solutions are verified by inserting them into original equations.The computations are assisted with 3D graphs to analyze the propagation dynamics of these rogue waves.Physical properties of these waves are governed by different parameters that are discussed in details. 展开更多
关键词 Generalized Hirota-Satsuma-Ito(HSI) equation The new extended(3+1)-dimensional Jimbo-Miwaequation Symbolic computation approach Bilinear form Rogue wave solutions
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A new and best approach for early detection of rotor and stator faults in induction motors coupled to variable loads
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作者 Abderrahim ALLAL Boukhemis CHETATE 《Frontiers in Energy》 SCIE CSCD 2016年第2期176-191,共16页
Today, induction machines are playing, thanks to their robustness, an important role in world industries. Although they are quite reliable, they have become the target of various types of defects. Thus, for a long tim... Today, induction machines are playing, thanks to their robustness, an important role in world industries. Although they are quite reliable, they have become the target of various types of defects. Thus, for a long time, many research laboratories have been focusing their works on the theme of diagnosis in order to find the most efficient technique to predict a fault in an early stage and to avoid an unplanned stopping in the chain of production and costs ensuing. In this paper, an approach called Park's vector product approach (PVPA) was proposed which was endowed with a dominant sensitivity in the case in which there would be rotor or stator faults. To show its high sensitivity, it was compared with the classical methods such as motor current signature analysis (MCSA) and techniques studied in recent publications such as motor square current signature analysis (MSCSA), Park's vector square modulus (PVSM) and Park-Hilbert (P-H) (PVSMp_H). The proposed technique was based on three main steps. First, the three-phase currents of the induction motor led to a Park's vector. was calculated to show Secondly, the proposed PVPA the distinguishing spectral signatures of each default and specific frequencies. Finally, simulation and experimental results were presented to confirm the theoretical assumptions. 展开更多
关键词 induction motor incipient broken bar extended Park's vector approach spectral analysis interturn short-circuit Hilbert transform
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An integrated deterministic-stochastic approach for forecasting the long-term trajectories of COVID-19
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作者 Indrajit Ghosh Tanujit Chakraborty 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2021年第3期63-75,共13页
The ongoing coronavirus disease 2019(COVID-19)pandemic is one of the major health emergencies in decades that affected almost every country in the world.As of June 30,2020,it has caused an outbreak with more than 10 m... The ongoing coronavirus disease 2019(COVID-19)pandemic is one of the major health emergencies in decades that affected almost every country in the world.As of June 30,2020,it has caused an outbreak with more than 10 million confirmed infections,and more than 500,000 reported deaths globally.Due to the unavailability of an effective treatment(or vaccine)and insufficient evidence regarding the transmission mechanism of the epidemic,the world population is currently in a vulnerable position.The daily cases data sets of COVID-19 for profoundly affected countries represent a stochastic process comprised of deterministic and stochastic components.This study proposes an integrated deterministic–stochastic approach to forecast the long-term trajectories of the COVID-19 cases for Italy and Spain.The deterministic component of the daily-cases univariate time series is assessed by an extended version of the SIR[Susceptible–Infected–Recovered–Protected–Isolated(SIRCX)]model,whereas its stochastic component is modeled using an autoregressive(AR)time series model.The proposed integrated SIRCX-AR(ISA)approach based on two operationally distinct modeling paradigms utilizes the superiority of both the deterministic SIRCX and stochastic AR models to find the long-term trajectories of the epidemic curves.Experimental analysis based on the proposed ISA model shows significant improvement in the long-term forecasting of COVID-19 cases for Italy and Spain in comparison to the ODE-based SIRCX model.The estimated Basic reproduction numbers for Italy and Spain based on SIRCX model are found to be 4.78 and 3.25,respectively.ISA model-based results reveal that the number of cases in Italy and Spain between 11 May,2020–9 June,2020 will be 10,982(6383–15,582)and 13,731(3395–29,013),respectively.Additionally,the expected number of daily cases on 9 July,2020 for Italy and Spain is estimated to be 30(0–183)and 92(0–602),respectively. 展开更多
关键词 COVID-19 Integrated approach PREDICTION extended SIR model AR model
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扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果分析
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作者 丁帅 利文倩 +1 位作者 韦立广 邹瑜珑 《中外医药研究》 2024年第9期9-11,共3页
目的:分析扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果。方法:选取2021年1月—2023年1月钦州市第二人民医院神经外科收治的重型颅脑损伤患者86例作为研究对象,随机分为对照组和观察组,各43例。对照组采用大骨瓣减压术联合传... 目的:分析扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果。方法:选取2021年1月—2023年1月钦州市第二人民医院神经外科收治的重型颅脑损伤患者86例作为研究对象,随机分为对照组和观察组,各43例。对照组采用大骨瓣减压术联合传统快速减压术治疗,观察组采用扩大翼点入路逐步控制性减压术治疗。比较两组颅内压、美国国立卫生研究院脑卒中量表(NIHSS)评分、格拉斯哥昏迷指数(GCS)评分及预后情况。结果:开颅前,两组颅内压水平比较,差异无统计学意义(P>0.05);术后24、72 h,两组颅内压水平降低,观察组低于对照组,差异有统计学意义(P<0.05)。术前,两组NIHSS、GCS评分比较,差异无统计学意义(P>0.05);术后72 h,两组NIHSS评分降低,观察组低于对照组,两组GCS评分升高,观察组高于对照组,差异有统计学意义(P<0.05)。观察组预后良好率高于对照组,差异有统计学意义(P=0.030)。结论:扩大翼点入路逐步控制性减压手术治疗重型颅脑损伤的效果显著,可降低颅内压水平,改善患者神经功能、昏迷程度及预后。 展开更多
关键词 颅脑损伤 扩大翼点入路 逐步控制性减压手术
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一种新型永磁同步电机高阶滑模控制算法
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作者 于惠钧 蒋新春 +3 位作者 黄刚 刘捃锓 郭益武 王志刚 《电气自动化》 2024年第2期1-6,共6页
针对永磁同步电机控制系统易因外部扰动等不确定性影响而导致控制性能下降的问题,提出了一种基于改进自适应非奇异终端滑模控制器和滑模扰动观测器补偿技术的复合控制算法。选择新型自适应指数趋近律设计非奇异终端滑模转速环控制器,新... 针对永磁同步电机控制系统易因外部扰动等不确定性影响而导致控制性能下降的问题,提出了一种基于改进自适应非奇异终端滑模控制器和滑模扰动观测器补偿技术的复合控制算法。选择新型自适应指数趋近律设计非奇异终端滑模转速环控制器,新型趋近律可以在保证减少抖振的同时保证控制系统能够快速收敛,可动态适应被控系统的变化;利用扩展滑模扰动观测器实时估计系统中不确定性参数,并对控制器进行前馈补偿,且通过Lyapunov函数证明了其稳定性。仿真和试验结果表明,与PI控制、传统滑模控制方法相比,所提方法有效改善了抖振问题,提高了控制系统对电机的控制精度,提升了系统的鲁棒性和抗干扰性能。 展开更多
关键词 永磁同步电机 新型自适应指数趋近律 非奇异终端滑模控制 扩展滑模扰动观测器 前馈补偿 鲁棒性
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基于扩张状态观测器的PMLSM高阶自适应非奇异快速终端滑模控制 被引量:1
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作者 唐家勇 张博 +2 位作者 刘洋 郭金钢 杜航航 《国外电子测量技术》 2024年第4期124-132,共9页
为改善永磁直线同步电机控制系统的位置跟踪精度和鲁棒性,提出了一种基于扩张状态观测的高阶自适应非奇异快速终端滑模控制方案。首先,设计了一种高阶非奇异快速终端滑模面,通过引入反馈电流实现对电机位置、速度和电流的整体控制。其次... 为改善永磁直线同步电机控制系统的位置跟踪精度和鲁棒性,提出了一种基于扩张状态观测的高阶自适应非奇异快速终端滑模控制方案。首先,设计了一种高阶非奇异快速终端滑模面,通过引入反馈电流实现对电机位置、速度和电流的整体控制。其次,设计新型滑模趋近律,使控制系统能快速将误差趋近于零并削弱抖振。同时,引入自适应律估计并实时调整趋近律系数。最后,设计了扩张状态观测观测外部扰动,从而提高位置跟踪系统的动态和稳态性能。基于Lyapunov稳定性理论,证明了该控制系统的稳定性。通过仿真与实验验证,结果表明,提出的控制方法能有效提高系统的位置跟踪精度,并且增强了系统的抗干扰能力。 展开更多
关键词 永磁同步直线电机 新型趋近律 高阶非奇异快速终端滑模控制 扩张状态观测器
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