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Design concept development of a variable magnetization motorwith improved efficiency and controllable stiffness for roboticapplications

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Science China(Technological Sciences) 2019年第1期62卷 39-46页

作者： BAI Kun ZHU Lang YUAN Mi LEE Kok-Meng State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Woodruff School of Mechanical Engineering Georgia Institute of Technology

A variable magnetization(VM) motor by incorporating magnets that can be flexibly configured with variable magnetization process is proposed to meet the emerging requirements on motor efficiency and actuator compliance in robotic applications. A generalized spin torque model is established which provides a relationship between the motor torque and two different types of motor inputs, the current inputs and the magnet magnetizations. Avariable magnetization process is proposed based on the study of the hysteresis properties of the magnetic materials and the design criteria for implementing the variable magnetization process with current pulses are established. The feasibility of the variable magnetization is validated with experimental data and the motor functions and performances are numerically demonstrated and evaluated. The results show that the VM motor can maintain high efficiency by switching between two actuation modes. Controllable stiffness at different equilibria can be also achieved with the VM motor with instantaneous magnetizing current pulses.

关键词： compliant actuators direct-drive motors variable stiffness motors variable magnetization motors

Design and experimental research of angle self-compensation setup for BSDF measurement

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Chinese Optics Letters 2009年第5期7卷 403-406页

作者：齐超刘洪臣韦袁丽戴景民 School of Electrical Engineering and Automation Harbin Institute of Technology

When using a single reference to measure the bi-directional scattering distribution function （BSDF）, the incident zenith angle of the tested sample must be identical to that of the reference. In order to get the hemisphere space scattering characteristic on the sample surface, usually a motor drives the sample tilting, then the incident zenith angle is changed and needs to be the compensated by another motor. We mathematically deduce the expression of compensation angle when the incident zenith angle is changed by the rotation of motor. After the incident angle is compensated, the scattering zenith angle and azimuth angle are deduced too. The uncertainty of the system is 0.75%. Scattering measurements are performed on copper sample with visible light under different temperatures.

关键词： Distribution functions Electric drives motors

A comprehensive review on hybrid electric vehicles: architectures and components

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Journal of Modern Transportation 2019年第2期27卷 77-107页

作者： Krishna Veer Singh Hari Om Bansal Dheerendra Singh Power Electronics and Drives Laboratory Department of Electrical and Electronics Engineering Birla Institute of Technology and Science

The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability.

关键词： Hybrid electric vehicle Hybrid energy storage system Architecture Traction motors Bidirectional converter

LEAD SCREW LINEAR ULTRASONIC MOTOR USING BENDING VIBRATION MODES

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Transactions of Nanjing University of Aeronautics and Astronautics 2009年第2期26卷 89-94页

作者：张健滔黄卫清朱华赵淳生南京航空航天大学航空宇航学院

The operating principle of a lead screw linear ultrasonic motor using bending vibration modes is analyzed. The simplified beam bending vibration model is used to analyze the dynamics characteristics of the motor. Motion trajectory equations are derived for driving points of the stator. The motor operation and driving mechanisms are investigated. The vibration modes and the construction of the motor are analyzed by using the finite element method （FEM）. A prototype motor is built and its stator dimension is 13 mm × 13 mm× 30 mm. The motor is experimentally characterized and the maximum output force of 5- 2 N is obtained.

关键词： motors ultrasonic motor vibrations finite element method (FEM) traveling wave

Mitochondria: transportation, distribution and function during spermiogenesis

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Advances in Bioscience and Biotechnology 2010年第2期1卷 97-109页

作者： Xiao Sun Wan-Xi Yang 不详

Spermiogenesis is a dynamic process which includes organelle reorganization and new structure formation. The morphology and distribution of the mitochondria in germ cells change to accommodate the cellular requirement. Multiple molecular motors and related proteins participate in carrying and anchoring mitochondria to the midpiece during spermiogenesis and this process is regulated precisely. Energetic metabolism provides energy for cellular activity and influences sperm survival and motility directly. Ubiquitination of mitochondria takes place during spermiogenesis, which has been implicated in sperm quality control and mitochondrial inheritance. In light of the essential roles of mitochondria in energy production, calcium homeostasis and apoptosis, mitochondria dysfunction cause severe human diseases, such as male infertility. The present study paves a way for a more detailed exploration of the biology of mitochondria during spermiogenesis.

关键词： Spermiogenesis Mitochondria Molecular motors Sperm Motility Ubiquitination Infertility

An Evolving Fuzzy Classifier for Induction Motor Health Condition Monitoring

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Intelligent Control and Automation 2019年第4期10卷 129-141页

作者： Peter Luong Wilson Wang Department of Electrical and Computer Engineering Lakehead University Thunder Bay Canada Department of Mechanical Engineering Lakehead University Thunder Bay Canada.

Induction motor (IM) is commonly used in various industrial applications. Reliable online IM health condition monitoring systems are critically needed in industries to improve operational accuracy and safety of the IMs and the machinery. A new evolving algorithm is proposed to provide more decision-making transparency, as well as better classification and processing efficiency. The effectiveness of the developed intelligent classifier is examined by simulation and experimental tests.

关键词： Evolving Fuzzy Classifier Clustering Automatic Fault Diagnostics Induction motors

A Novel Current Sensor Technique for Brushless DC Motor Drives

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Advances in Manufacturing 2000年第1期4卷 42-48页

作者： Hui Tan Jian-zhong Jiang Xin-yao Wang Yong Wang School of Mechanical and Electronic Engineering and Automation Shanghai University Shanghai 200072 China

The torque output in a permanent magnet brushless DC motor (BLDCM) is usually controlled by regulating the motor phase currents. In this paper, three kinds of PWM strategies together with some critical review on traditional current measurements in a BLDCM drive system are discussed. A novel method for assessing the PWM information and measuring the motor phase currents by a dc link current sensor is proposed. An attractive feature of the proposed method is the simplicity with the current sample processing because there is no need to incorporate the conduction information of the power switches or diodes. Only the single sided PWM or the double sided complementary PWM is needed with the proposed technique.

关键词： current sampling sensor reduction motors drives

A New Structure of Multilevel Inverter with Reduced Number of Switches for Electric Vehicle Applications

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Energy and Power Engineering 2011年第2期3卷 198-205页

作者： M. Ebadpour M. B. B. Sharifian S. H. Hosseini 不详

Both Hybrid Electric Vehicles (HEVs) and Electric Vehicles (EVs) need a traction motor and a power in-verter to drive the traction motor. The requirements for the power inverter include high peak power, opti-mum consumption of energy, low output harmonics and inexpensive circuit. In this paper, a new structure of multilevel inverter with reduced number of switches is proposed for electric vehicle applications. It consists of an H-bridge and an inverter in each phase which produces multilevel voltage by switching the dc voltage sources in series. As the number of switches are reduced, both conduction and switching losses will be de-creased, which leads to increase the efficiency of converter. The size and power consumption of driving cir-cuits are also reduced. The proposed three phase inverter can produces more number of voltage levels in the same number of the voltage source and reduced number of switches compared to the conventional inverters. This structure minimizes the total harmonic distortion (THD) of the output voltage waveforms. The structure of proposed multilevel inverter, modulation method, switching losses, THD calculation and simulation re-sults with PSCAD/EMTDC software are shown in this paper.

关键词： Cascaded H-Bridge Electric Vehicles (EVs) Hybrid Modulation Inverters Traction motors

Dynamic Equivalent Method of Motor Loads for Power Systems Based on the Weighted

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Journal of Power and Energy Engineering 2014年第4期2卷 416-422页

作者： Bo Hong Hanmei Hu Ting Chen Qinfeng Li College of Electrical Engineering and New Energy China Three Gorges University Yichang China College of Electrical Engineering and New Energy China Three Gorges University Yichang China

Dynamic equivalence can not only largely reduce the system size and the computation time but also stress the dominant features of the system [1]-[3]. This paper firstly recommends the basic concept of dynamic equivalent and the status of both domestic and abroad development in this area. The most existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors. In addition, the existing polymerization method which is based on the frequency domain algorithm of induction electric machines parameters takes a long time to equivalent for the large system, then the new method based on the weighted is proposed. Then, the basic steps for dynamic equivalence with the weighted method are introduced as follows. At first, the clustering criterion of motor loads based on time domain simulation is given. The motors with similar dynamic characteristics are classified into one group. Then, the simplication of the buses of motors in same group and network is carried out. Finally, parameters of the equivalent motor are calculated and the equivalent system is thus obtained based on the weighted. This aggregation method is applied to the simple distribution system of 4 generators. Simulation results show that the method can quickly obtain polymerization parameters of generator groups and the aggregation model retains the dynamic performance of the original model with good accuracy, the active and reactive power fitting error is smaller as well.

关键词： Power System Dynamic Equivalent Induction motors Parameter Aggregation The Weighted Method