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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils
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作者 Belemdara Dingamadji Hilaire Mbaïnaïbeye Jérôme Guidkaya Golam 《Journal of Electromagnetic Analysis and Applications》 2024年第2期11-23,共13页
The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the tw... The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet. 展开更多
关键词 MODELLING 3D Finite Elements Magnetic Flux Hybrid stepping motor
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ROBUST ADAPTIVE CONTROL SCHEME FOR IMPROVING LOW-SPEED PROFILE TRACKING PERFORMANCE OF HYBRID STEPPING MOTOR SERVO DRIVE 被引量:3
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作者 陈卫东 容启亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期8-16,共9页
A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precisio... A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precision profile tracking at a low speed. In order to construct a completely integrated control design philosophy to reduce torque ripple and at the same time to enhance tracking performance, the properties of nonlinear uncertainties in the system dynamics are uncovered, and then incorporated into the design of the controller. The system uncertainties concerned with ripple dynamics and other external disturbances are composed of two categories. The first category of uncertainties with linear parameterization arising from the detention effect is dealt with by the wellknown adaptive control method. A robust adaptive method is used to deal with the second category of uncertainties resulting from the non-sinusoidal flux distribution. The μ-modification scheme is used to cease parameter adaptation by the robust adaptive control law, thus ensuring that the trajectory tracking error asymptotically converges to a pre-specified boundary. Experiments are performed with a typical hybrid stepping motor to test its profile tracking accuracy. Results confirm the proposed control scheme. 展开更多
关键词 robust adaptive control tracking control stepping motor torque ripple
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Linear Piezoelectric Stepping Motor with Broad Operating Frequency 被引量:2
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作者 陈西府 王寅 +1 位作者 孙梦馨 黄卫清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第2期137-142,共6页
The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displac... The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displacement output characteristics of piezoelectric stacks,the trajectory at the drive foot of stator is firstly produced with two space quadrature piezoelectric actuators excited by sawtooth wave and square wave.Secondly,the friction drive principle of motor is used to analyze the working mechanisms of the continuous stepping motion.Finally,the motor prototype is designed and experiments are carried out.The experimental result shows that the motor can stably operate within the scope of 350 Hz to 750 Hz.When the excitation voltage is 30 Vand pre-load is 3Nor10 N,the lateral amplitude of the drive foot is approximately 4μm and the stable average interval ranges from3.1μm to 3.2μm with the error rate of 5%—7.5%. 展开更多
关键词 linear motor piezoelectric stack stepping motor broad operating frequency
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MINIMUN TIME OPTIMAL CONTROL OF STEPPING MOTOR
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作者 Luo An(College of Information Engineering, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1995年第2期54-58,共5页
The paper describes a new method of the stepping motor moimun time optimal control with closed-loop control. A mathematical model and optimal control strategy for the optimal control of stepping motor are proposed. ... The paper describes a new method of the stepping motor moimun time optimal control with closed-loop control. A mathematical model and optimal control strategy for the optimal control of stepping motor are proposed. Realizing technology for accelerating 展开更多
关键词 OPTIMAL CONTROL stepping motor MICROCOMPUTER
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Static-torque Characteristics of Three-phase Hybrid(HB) Stepping Motors and Influence of Way of Winding Connection on Operating Characteristics of Motors of This Kind
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作者 刘宝廷 郑萍 崔淑梅 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第4期59-62,共4页
The paper presents the static-torque characteristics of three-phase hybrid stepping motors and discusses the influence of way of winding connection on operating characteristics of motors of this kind.
关键词 stepping motors TORQUE CHARACTERISTICS WINDING CONNECTION
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Numerical Modeling of the Coupled Electromagnetic and Mechanical Phenomena of Linear Stepping Motors
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作者 Mustapha Zaouia Nacereddine Benamrouche M'hemed Rachek 《Journal of Electromagnetic Analysis and Applications》 2012年第1期1-8,共8页
In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepp... In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepping Motor (LSRSM). After the resolution of the non-linear electromagnetic equation governing the behaviour of the different materials of the motor using the nodal-based finite element method, this equation is then coupled to the mechanical equation firstly through the magnetic force computed by Maxwell stress tensor, and secondly by the modified flux distribution due to the moving part. Because of the precision required in the mobile part displacement and the very small air gap of stepping motors, the simulation of the movement is assured by the Macro-Element (ME) technique compared to other movement techniques that present many disadvantages. The validity of the developed model is verified through the comparison of the computed displacement of the LSRSM moving part with those given experimentally [2]. The Results shows satisfactory agreement. The obtained dynamic characteristics, particularly the starting magnetic force, are obtained by considering two values of the supplying currents. 展开更多
关键词 NUMERICAL Modeling Electromagnetic-Mechanical PHENOMENA Finite Element MOVEMENT stepping motors
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A hybrid stepping motor system with dual CPU
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作者 高晗璎 赵克 孙力 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期382-386,共5页
An indirect method of measuring the rotor position based on the magnetic reluctance variation is presented in the paper. A single-chip microprocessor 80C196KC is utilized to compensate the phase shift produced by the ... An indirect method of measuring the rotor position based on the magnetic reluctance variation is presented in the paper. A single-chip microprocessor 80C196KC is utilized to compensate the phase shift produced by the process of position signals. At the same time, a DSP (Data Signal Processor) unit is used to realize the speed and current closed-loops of the hybrid stepping motor system. At last, experimental results show the control system has excellent static and dynamic characteristics. 展开更多
关键词 closed-loop control indirect measurement hybrid stepping motor
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Research on simulation system of virtual three-phase stepping motor
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作者 HAN Jiang LIU Youyu +1 位作者 XIA Lian TIAN Xiaoqing 《Computer Aided Drafting,Design and Manufacturing》 2012年第2期74-77,共4页
To change the current phenomenon of "Being an armchair strategist" in the research of a stepping motor, the virtual simu- lation system of stepping motor was developed using virtual reality technique. The basic prin... To change the current phenomenon of "Being an armchair strategist" in the research of a stepping motor, the virtual simu- lation system of stepping motor was developed using virtual reality technique. The basic principle of stepping motor was expounded. The development strategy of the simulation software is introduced. Some key problems and their solutions, including coordinate transformation of rotor and order of on-off electricity for stator, were put forward in system development. Finally, there are three virtual simulation examples of the on-off electricity way in this paper. This work provides a valuable auxiliary tool for the study of the stepping motor. 展开更多
关键词 stepping motor servo system virtual reality software development Visual Basic
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Development of an underactuated prosthetic hand with the step motor 被引量:4
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作者 赵大威 Jin Minghe Jiang Li Shi Shicai Liu Hong 《High Technology Letters》 EI CAS 2006年第4期341-345,共5页
We present the development of a novel prosthetic hand based on the underactuated mechanism. The aim is focused on increasing its dexterity while keeping the same dimension and weight of a traditional prosthetic device... We present the development of a novel prosthetic hand based on the underactuated mechanism. The aim is focused on increasing its dexterity while keeping the same dimension and weight of a traditional prosthetic device. The hybrid step motor is used as the actuator, which enables the finger to keep enough high contact torque on the grasped object with less energy consumption provided by the holding torque. The grasping force of the finger is estimated from the base joint torque, and the adoption of impedance control has provided compliance in the grasping. Also a parallel observer is used to switch over between the impedance control and the torque holding mode. The experimental results show the effectiveness of the design and control strategy. 展开更多
关键词 prosthetic hand UNDERACTUATED torque control step motor
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Detection of rotor position by harmonic back EMF of hybrid step motor
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作者 张劲松 徐殿国 王宗培 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期85-88,共4页
The magnhc network model of a hybrid step motor is established by the air gap rate permeance method,and the expression of harmonic back EMF is deduced, and from the analysis above, a vovel use of harmonic backEMF sed ... The magnhc network model of a hybrid step motor is established by the air gap rate permeance method,and the expression of harmonic back EMF is deduced, and from the analysis above, a vovel use of harmonic backEMF sed to extract rotor peition is proposed and a new position sensor integral with the motoris designed .Experi-ments verified the correctness of the theorecal analysis. Ths type of rotor position sensor lays a foundation for closed-loop conrol of step motor. 展开更多
关键词 HYBRID step motor air gap rate PERMEANCE magnetic network model HARMONIC BACK EMF position sensor
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Six-step Voltage Control of PM Brushless AC Motors under High Speed Flux-weakening Operation for EV/HEV Applications 被引量:1
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作者 诸自强 《电力电子技术》 CSCD 北大核心 2008年第10期2-4,13,共4页
The torque-speed characteristics of brushless motor having an interior permanent magnet rotor and a sinusoidal back-emf waveform are compared experimentally when it is operated in brushless AC(BLAC) mode and brushless... The torque-speed characteristics of brushless motor having an interior permanent magnet rotor and a sinusoidal back-emf waveform are compared experimentally when it is operated in brushless AC(BLAC) mode and brushless DC (BLDC) modes with both 2-phase,120° conduction(BLDC-120) and 3-phase,180° conduction(BLDC-180).Particular emphasis is on high-speed,six-step voltage controlled,flux-weakening operation.It is shown that for EV/HEV applications,even for interior PM brushless motors which have sinusoidal back-emf waveforms,in order to achieve maximum torque per ampere capability over wide operation speed range,it is advantageous to employ a hybrid operation mode-BLAC operation in the constant torque region and six-step voltage control(BLDC-180 operation,together with current phase control) in the flux-weakening region. 展开更多
关键词 电压 控制方法 交流电动机 频率
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An Experimental Investigation on the Dynamic Behavior of Step Motor Drives
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作者 Paolo Righettini Roberto Strada Alberto Oldani Andrea Ginammi 《Journal of Mechanics Engineering and Automation》 2012年第7期431-440,共10页
Step motors, compared to other drive systems, are low-cost and easy to use devices. However, despite these undeniable advantages, they are characterized by some critical running conditions, due to the loss of synchron... Step motors, compared to other drive systems, are low-cost and easy to use devices. However, despite these undeniable advantages, they are characterized by some critical running conditions, due to the loss of synchronization between the stator's magnetic field and the rotor. In order to theoretically investigate such a behavior, several complex mathematical models have been developed, which require several parameters to be defined. For most step motors, such parameters cannot be easily drawn from their data-sheets; on the contrary, in this paper the authors refer to a simplified electro-mechanical model where the most of the parameters are known from data-sheets. The dependence between electrical and mechanical quantities can be investigated by an experimental point of view. At this aim, a specific novel test rig has been designed and developed for either static or dynamic characteristics measurement of small size step motors. In particular, the test rig allow to measure rotor's angular position, motor's torque, currents flowing in the motor's phases. The paper ends with the report of the results of several experimental tests, carried-out on a small-size motor in different running conditions, and with some preliminary remarks on the basis of the measures analysis. 展开更多
关键词 step motor drives experimental investigation test-rig dynamic behavior electro-mechanical model
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A Step Motor Driver For the Let-off Mechanism of Looms
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作者 池洪 陈明 +1 位作者 孙志宏 毕丽蕴 《Journal of China Textile University(English Edition)》 EI CAS 1998年第1期14-16,共3页
It is simple with good quality,and versatile with low costto use a step motor drive for the let-off mechanism ofweaving machines.This paper deals with the investiga-tion of this mechanism about the warp tension detect... It is simple with good quality,and versatile with low costto use a step motor drive for the let-off mechanism ofweaving machines.This paper deals with the investiga-tion of this mechanism about the warp tension detectingand the design of the step motor drive system,which ispracticable,reliable and with low power consumption.So it is worthwhile to spread and push forward its appli-cation. 展开更多
关键词 step motor let-off mechanism WARP tension testing
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两相式混合步进电机速度和位移控制案例设计 被引量:1
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作者 马清艳 《机械工程与自动化》 2024年第1期8-10,共3页
步进电机在电脉冲信号的控制下能实现一定的角位移或线位移,掌握步进电机的控制技术非常重要。以两相混合式步进电机为控制对象,以单片机AT89C52和可编程计数器/定时器8253为主对电机进行速度和位移控制设计,对某一具体案例采用Proteus... 步进电机在电脉冲信号的控制下能实现一定的角位移或线位移,掌握步进电机的控制技术非常重要。以两相混合式步进电机为控制对象,以单片机AT89C52和可编程计数器/定时器8253为主对电机进行速度和位移控制设计,对某一具体案例采用Proteus软件进行设计与仿真,包括控制电路和程序的设计。仿真和实验结果表明:该系统结构简单、容易实现、成本低,可用于其他步进电机的控制,并为教学或工程应用提供了参考。 展开更多
关键词 两相式混合步进电机 速度控制 位移控制 设计
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基于阶跃激励响应的牵引电机定子早期匝间短路故障诊断方法 被引量:1
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作者 耿民 秦嘉翼 +2 位作者 刘明杰 张川宝 王喜莲 《机车电传动》 2024年第2期158-164,共7页
为了实现对牵引电机定子绕组匝间短路早期故障的可靠诊断,文章提出了一种基于阶跃激励稳态响应电流的故障诊断方法。首先根据牵引电机三相定子绕组匝间短路模型,对定子绕组任意两相施加阶跃激励,推导出3种情况下的响应电流表达式,并依... 为了实现对牵引电机定子绕组匝间短路早期故障的可靠诊断,文章提出了一种基于阶跃激励稳态响应电流的故障诊断方法。首先根据牵引电机三相定子绕组匝间短路模型,对定子绕组任意两相施加阶跃激励,推导出3种情况下的响应电流表达式,并依据响应电流稳态值的变化特征提出新的故障特征分量;然后,搭建故障电机仿真模型,分析短路电阻和短路故障严重程度对响应电流的影响,研究故障特征分量对早期匝间短路故障诊断的有效性与可靠性;最后搭建试验平台,分析当电机固有不对称时,匝间短路故障对故障特征分量的影响。仿真与试验结果表明,该故障特征分量可以表示早期的匝间短路故障及其严重程度,并且能滤除电机固有不对称的影响。基于阶跃激励稳态响应电流的诊断方法操作便捷,结果可靠性高,对保护牵引系统的安全具有极大意义,且具备极大的工程应用价值。 展开更多
关键词 牵引电机 定子绕组匝间短路 故障诊断 阶跃响应
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基于流固耦合的固体发动机复合喷管烧蚀型面演变
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作者 陈旭龙 闫航 +2 位作者 张春宇 冯喜平 侯晓 《推进技术》 EI CAS CSCD 北大核心 2024年第7期113-123,共11页
由于材料烧蚀性能不同,固体火箭发动机复合喷管普遍存在烧蚀台阶,严重影响喷管结构完整性,降低喷管性能。为了预示固体火箭发动机复合结构喷管内不同热防护材料交接处的烧蚀台阶型面演变过程,建立了一种能反映喷管两相流环境下防热材料... 由于材料烧蚀性能不同,固体火箭发动机复合喷管普遍存在烧蚀台阶,严重影响喷管结构完整性,降低喷管性能。为了预示固体火箭发动机复合结构喷管内不同热防护材料交接处的烧蚀台阶型面演变过程,建立了一种能反映喷管两相流环境下防热材料烧蚀过程的流固耦合计算方法。依据热化学烧蚀与粒子侵蚀机理,考虑瞬态计算中烧蚀型面的退移,模拟了石墨-高硅氧/酚醛复合喷管烧蚀型面演化过程,验证了计算方法的有效性。模拟得到的收敛段烧蚀台阶型面与实验结果吻合较好,扩张段台阶计算深度略低于实验值。仿真结果表明:收敛段受热化学烧蚀与粒子侵蚀共同作用,两种材料粒子侵蚀速率的差异可达0.36 mm/s,是收敛段烧蚀台阶形成的主要原因,扩张段烧蚀台阶的产生仅受热化学烧蚀的影响,交接处退移速率最大差值为0.044 mm/s;烧蚀台阶形成后,拐角处暴露的石墨材料会受到较强的粒子冲刷效应;喷管喉部前端的石墨材料因烧蚀型面变化,喷管实际喉部向出口移动1.96 mm。 展开更多
关键词 固体火箭发动机喷管 烧蚀台阶 热化学烧蚀 粒子侵蚀 数值仿真
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探测器阵列高精度二维标定平台控制系统设计
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作者 于龙昆 李智祥 +2 位作者 温小辉 刘辉 谭逢富 《量子电子学报》 CAS CSCD 北大核心 2024年第2期300-309,共10页
为了实现快速、高精度探测器阵列标定,对探测器阵列高精度二维标定平台控制系统进行了研究,设计了采用单片机控制步进电机加编码器的闭环位移控制系统。介绍了该平台的标定原理和硬、软件控制系统设计,并对控制PID算法进行了研究,最后... 为了实现快速、高精度探测器阵列标定,对探测器阵列高精度二维标定平台控制系统进行了研究,设计了采用单片机控制步进电机加编码器的闭环位移控制系统。介绍了该平台的标定原理和硬、软件控制系统设计,并对控制PID算法进行了研究,最后搭建了标定系统对控制系统进行综合测试。实验结果表明该控制系统有良好的控制能力,平台在600 mm×600 mm的有效行程内定位精度可达-11~12μm,十次单点测试数据变异系数为0.13%,连续模式下平均测量误差为1.65%。该平台设计满足探测器阵列的标定要求,为探测器阵列标定提供了一种有效手段。 展开更多
关键词 控制工程 探测器阵列标定 二维平台 闭环控制系统 步进电机 PID算法
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基于非线性观测器的永磁同步电机位置估计算法研究
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作者 张琳元 张清艺 张志锋 《电机与控制应用》 2024年第3期79-85,共7页
为提高表贴式永磁同步电机无位置传感器控制中转子位置和速度的估计精度,提出了一种改进型非线性观测器。通过重构非线性观测器的数学模型,构建了误差方程,利用Lyapunov理论对误差方程进行了稳定性分析。并基于稳定性条件提出了一种误... 为提高表贴式永磁同步电机无位置传感器控制中转子位置和速度的估计精度,提出了一种改进型非线性观测器。通过重构非线性观测器的数学模型,构建了误差方程,利用Lyapunov理论对误差方程进行了稳定性分析。并基于稳定性条件提出了一种误差项步长优化方法,实现了非线性观测器的步长增益自调节。仿真与试验结果表明,改进型非线性观测器具有良好的动态性能,验证了其可行性。 展开更多
关键词 永磁同步电机 无位置传感器 非线性观测器 步长优化
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经皮穴位电刺激联合阶梯式运动想象疗法对脑卒中上肢和手功能的闭环康复疗效分析 被引量:1
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作者 高佳佳 王鹤玮 +6 位作者 刘兰兰 夏小迪 纪兆颖 王晓文 刘强 曹叶凡 陈瑶 《同济大学学报(医学版)》 2024年第2期228-235,共8页
目的探究经皮穴位电刺激联合阶梯式运动想象疗法对脑卒中患者上肢和手功能康复的疗效。方法选取2021年1月—2023年4月上海市静安区北部地区医疗服务共同体成员单位脑卒中患者80例随机分为试验组(n=40)和对照组(n=40)。两组患者均接受常... 目的探究经皮穴位电刺激联合阶梯式运动想象疗法对脑卒中患者上肢和手功能康复的疗效。方法选取2021年1月—2023年4月上海市静安区北部地区医疗服务共同体成员单位脑卒中患者80例随机分为试验组(n=40)和对照组(n=40)。两组患者均接受常规康复,试验组在此基础上接受基于“闭环康复”的经皮穴位电刺激联合阶梯式运动想象疗法,而对照组则接受经皮穴位电刺激治疗和注意力无效对照干预,总共干预4周。分别于治疗前后对两组患者进行Fugl-Meyer上肢运动功能评定量表(Fugl-Meyer assessment-upper extremities,FMA-UE)、积木盒障碍测试(boxing and blocking test,BBT)、改良Ashworth评分(modified Ashworth scale,MAS)和改良Barthel指数(modified Barthel index,MBI)的评定,并采用手心理旋转测试评价患者干预前的运动想象能力。结果试验组和对照组分别有35名和36名患者完成研究的所有干预和评定。治疗后两组FMA-UE、BBT、MBI评分均显著改善(t>3.545,P<0.001),试验组FMA-UE总分和近、远端子项目评分均显著优于对照组(t>2.187,P<0.05)。相关性分析显示试验组患者FMA-UE的远端子项目评分变化值与治疗前心理旋转反应时间呈负相关(r=-0.676,P<0.001)。结论经皮穴位电刺激治疗联合阶梯式运动想象疗法可有效改善脑卒中的上肢和手运动功能,其疗效与患者的基线运动想象能力有关。 展开更多
关键词 脑卒中 经皮穴位电刺激 阶梯式运动想象 上肢 手功能
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慢行交通模型框架研究——以北京东坝北西区为例
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作者 张政 焦咏欣 +5 位作者 靳瑾 金山 宣晶 刘昊 张鑫 黄斌 《交通工程》 2024年第5期98-105,共8页
针对既有交通模型主要对中长出行距离的机动化出行进行建模,缺乏对慢行交通行为建模,无法满足慢行示范区慢行需求预测。本文梳理了各种慢行交通方式的出行特征,将研究区域划分为低碳示范区内外两类空间单元,低碳示范区内空间单元细分为... 针对既有交通模型主要对中长出行距离的机动化出行进行建模,缺乏对慢行交通行为建模,无法满足慢行示范区慢行需求预测。本文梳理了各种慢行交通方式的出行特征,将研究区域划分为低碳示范区内外两类空间单元,低碳示范区内空间单元细分为地块颗粒度,示范区外保持原交通小区颗粒度。基于北京综合交通大调查数据,采用多元回归和重力模型分别构建示范区内外的出行生成和分布模型。依据慢行距离转移曲线确定各慢行方式分担率,再利用logit模型得到剩余方式分担率,根据测试场景下慢行设施设置情况确定路网成本并采用CUBE软件进行示范区内慢行需求交通分配。对北京市东坝北西区远期慢行交通需求进行预测。结果表明,本文构建慢行交通模型框架可对示范区内慢行需求预测,模型结果可支撑区域内慢行设施有无对目的地的可达性分析,助力绿色低碳慢行示范区慢行交通规划建设。 展开更多
关键词 交通需求模型 慢行出行特征 慢行交通模型 四阶段法
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