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Electromagnetic torque Analysis of Wind-Driven SRG with Ferrite Magnet

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CES Transactions on Electrical Machines and Systems 2020年第3期4卷 172-179页

作者： Kitaba Tefera Praveen Tripathy Ravindranath Adda Indian Institute of Technology Guwahati India Department of Electronics and Electrical Engineering Indian Institute of Technology GuwahatiIndia

The present paper analyses the effect of placing the ferrite magnet into the rotor air barrier of synchronous reluctance generators(SRG)on its electromagnetic performance.The paper uses a difference of average electromagnetic torque and ripple torque as a measure of the performance index.Here,in the analysis,a magnetic material is placed in the middle of each air barrier,and its size is symmetrically increased on both sides to increase the percentage of the volume of the magnetic material.The effect of an increase in the volume of the magnetic material on its performance is presented.Moreover,the variation in electromagnetic features such as the d−and q-axes inductance and flux linkage are also explored and compared for different volumes and ferrite material.In the present work,finite element analysis is used to get the electromagnetic performance.The paper also includes hardware validation on the fabricated prototype of SRG(without ferrite magnet),but SRG with a ferrite magnet only includes the results with FEA simulation.

关键词： Ferrite material FEA torque Synchronous reluctance generator

Calculation for electromagnetic torque of double-stator-permanent magnet synchronous motor

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Journal of Harbin Institute of Technology(New Series) 2000年第2期7卷 58-61页

作者：柴凤朱春波程树康 Dept. of Electric Engineering Harbin Institute of Technology Harbin 150001 China

Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the development of prototypes, and discusses the comparison of the motor under development with the conventional motors with the same volume, stator structure, and magnet shape, and concludes the motor under development is one of the ways to improve the performance/volume ratio of motors.

关键词： double stator electromagnetic torque synchronous motor

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CES Transactions on Electrical Machines and Systems 2022年第3期6卷 223-224页

作者： Wenxiang Zhao Zheng Wang Xuzhen Huang Dawei Li Xiao Liu Wenliang Zhao Ying Xie Xianglin Li Guodong Yu Liang Xu the School of Electrical Information Engineering Jiangsu University Southeast University China Nanjing University of Aeronautics and Astronautics China Huazhong University of Science and Technology China Hunan University China Shandong University China Harbin University of Science and Technology China Qingdao University China Harbin Institute of Technology China Jiangsu University China

WITH the rapid development of aerospace, industrial robots, numerical control machine tool and other high-end equipment, electrical machine system, as the core power source, requires a higher torque performance. High torque density means that the machine has a smaller size and weight, which is critical in aerospace, electric vehicles and other applications where machine volume and mass requirements are stringent. In industrial robots and numerical control machine tools, low torque pulsation has an important effect on positioning accuracy and running smoothness. In this context, high torque performance machine system has gradually become an important research and development branch in the field.

关键词： Message system torque

Experimental study of drag reduction characteristics related to the multifactor coupling of a bionic jet surface

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Journal of Hydrodynamics 2019年第1期31卷 186-194页

作者： Yun-qing Gu Song-wei Yu Jie-gang Mou Tian-xing Fan Shui-hua Zheng Gang Zhao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

To study the drag reduction of a jet surface,an experiment is conducted with a gyrorotor model.The aim of this study is to analyze the influence of the jet aperture,the jet angle and the rotational velocity coupled with the jet velocity on the friction torque acting on a jet surface model by using a jet surface drag reduction testing experimental platform.The drag reduction characteristics of the jet surface are also studied.The results show that the maximum drag reduction rate is attained when the jet diameter is 5 mm and the jet velocity is 1.2 m/s.The influence of the jet velocity on the drag reduction rate decreases as the diameter decreases.However,the maximum drag reduction rate can be attained when the angle of the jet is 30° and the velocity of the jet is 1.0 m/s.When the jet diameter is small,the influence of the jet velocity on the drag reduction rate is small,whereas the maximum drag reduction rate is attained when the jet angle is 30° and the jet velocity is 1.0 m/s.When the jet angle is 15°,the drag reduction rate fluctuation is distinct.The maximum drag reduction rate is attained when the rotational velocity is 2 100 r/min and the jet velocity is 1.0 m/s.The results show that the best scheme is A2B2D3 A maximum drag reduction rate of 8.57% can be attained.The effective control of the jet effect on the separation of the boundary layer demonstrates the drag reduction principle of a bionic jet surface.

关键词： Drag reduction bionic jet surface friction torque coupling experiment

Design and simulation of electrical dynamometer using improved DTC induction motor driver

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Journal of Central South University 2017年第6期24卷 1360-1368页

作者：朱成礼王延忠侯良威 School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China

AC motors, especially the squirrel cage induction motors have the advantages of simple structure, good reliability and low cost. They are more suitable to be used as electrical dynamometers to provide dynamic load for bench test systems. But, the speed and torque of induction motors are not easy to be controlled accurately. In this work, an electrical dynamometer based on the induction motor is proposed. In order to get better control performance of torque and speed of induction motor, an improved direct torque control method(DTC) is also developed based on the space vector modulation(SVM) technique. The performance of the proposed dynamometer system is validated in the Matlab/Simulink platform. The simulation results show that the new dynamometer has good torque and stator flux response. And the torque and stator current ripples of it are reduced significantly compared with using the conventional DTC method.

关键词： dynamometer induction motor direct torque control (DTC) direct torque control method-space vector modulation DTC-SVM PI controller

Contribution of the FPGAs for Complex Control Algorithms: Sensorless DTFC with an EKF of an Induction Motor

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International Journal of Automation and computing 2019年第2期16卷 226-237页

作者： Saber Krim Soufien Gdaim Abdellatif Mtibaa Mohamed Faouzi Mimouni Laboratory of Electronics and Microelectronics EE Faculty of SciencesUniversity of Monastir Research Unit "Industrial Systems Study and Renewable Energy" University of Monastir Polytechnic School of Engineering (PSE) University of Sousse National Engineering School University of Monastir

In a conventional direct torque control(CDTC) of the induction motor drive, the electromagnetic torque and the stator flux are characterized by high ripples. In order to reduce the undesired ripples, several methods are used in the literature. Nevertheless,these methods increase the algorithm complexity and dependency on the machine parameters such as the space vector modulation(SVM). The fuzzy logic control method is utilized in this work to decrease these ripples. Moreover, to eliminate the mechanical sensor the extended kalman filter(EKF) is used, in order to reduce the cost of the system and the rate of maintenance. Furthermore, in the domain of controlling the real-time induction motor drives, two principal digital devices are used such as the hardware(FPGA) and the digital signal processing(DSP). The latter is a software solution featured by a sequential processing that increases the execution time. However, the FPGA is featured by a high processing speed because of its parallel processing. Therefore, using the FPGA it is possible to implement complex algorithms with low execution time and to enhance the control bandwidth. The large bandwidth is the key issue to increase the system performances. This paper presents the interest of utilizing the FPGAs to implement complex control algorithms of electrical systems in real time. The suggested sensorless direct torque control using the fuzzy logic(DTFC) of an induction motor is successfully designed and implemented on an FPGA Virtex 5 using xilinx system generator. The simulation and implementation results show proposed approach s performances in terms of ripples, stator current harmonic waves, execution time, and short design time.

关键词： Direct torque control fuzzy logic control (FLC) extended Kalman filter Xilinx system generator (XSG) field programmable gate array (FPGA)

Design and Tests of Biomimetic Blades for Soil-rototilling and Stubble-breaking

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Journal of Bionic Engineering 2015年第3期12卷 495-503页

作者： Jin Tong Wenfeng Ji Honglei Jia Donghui Chen Xiaowan Yang The Key Laboratory of Bionic Engineering (Ministry of Education China) and the College of Biological and Agricultural Engineering Jilin University (Nanling Campus) Changchun 130022 China The College of Engineering Huazhong Agricultural University Wuhan 430070 China

Biomimetic blades for soil-rototilling and stubble-breaking were designed learning from the geometrical structure of the tips of toes of mole rat （Scaptochirus moschatus）. The orientation, the number and the central angle of the biomimetic structure were taken as the testing factors. The optimal structure of the biomimetic blade was determined through the tests of soil-rototilling and stubble-breaking operation in an indoor soil bin. The optimal combination of the biomimetic structure pa- rameters is that three arc concave teeth are equally arranged on the front cutting edge with a central angle of 60°. The results of comparative tests between the optimal biomimetic blade and a conventional universal blade show the torque acting on the biomimetic blade is lower during soil-rototilling and stubble-breaking operations. The results of field tests show that the working quality of the biomimetic blades meets the requirements of the national standard of China. Tests of soil-rototilling show that, when the orientation of the biomimetic structure was at low and middle levels, the torque ofbiomimetic blades decreased from 34.17 N·m to 31.03 N·m. The torque also decreased with the increase of the number of biomimetic structure. The average torques were 34.57 N·m, 33.44 N·m and 31.37 N·m, respectively. The maximum different value between two levels of central angle was 0.41 N·m. Tests in field indicate that for soil-rototilling operation, the tillage depth is deeper than 80 mm, the soil-crushing rate （length of soil block less than 40 mm） is over 50 %, and the vegetation coverage rate is over 55 %. For stubble-breaking operation, the stubble-breaking depth is deeper than 70 ram, the stubble-breaking rate （length of stubble less than 40 mm） is over 60%, and the stubble coverage rate is over 80%, which can meet the stubble-breaking requirement of corn.

关键词： biomimetics mole rat （Scaptochirus moschatus） soil-rototilling stubble-breaking torque working quality

Performance analysis of a wave energy converter using numerical simulation technique

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Science China(Technological Sciences) 2010年第1期53卷 13-18页

作者： Mohammed Asid ZULLAH Deepak PRASAD Mohammed Rafiuddin AHMED Young-Ho LEE Graduate School Korea Maritime University Dongsam-dong Youngdo-kuBusan 606-791Republic of Korea Division of Mechanical Engineering University of the South PacificPrivate Mail BagLaucala CampusSuvaFiji Islands Division of Mechanical & Information Engineering Korea Maritime UniversityDongsam-dong Youngdo-kuBusan 606-791Republic of Korea

A general purpose viscous flow solver Ansys CFX was used to study a Savonius type wave energy converter in a 3D numerical viscous wave tank.This paper presents the results of a computational fluid dynamics(CFD) analysis of the effect of blade configuration on the performance of two Savonius rotors for wave energy extraction.A piston-type wave generator was incorporated in the computational domain to generate the desired incident waves.A complete OWC system with a 3-bladed Savonius rotor was modeled in a three dimensional numerical wave tank and the hydrodynamic conversion efficiency was estimated.The flow over the rotors was assumed to be two-dimensional(2D),viscous,turbulent and unsteady.The CFX code was used with a solver of the coupled conservation equations of mass,momentum and energy,with an implicit time scheme and with the adoption of the hexahedral mesh and the moving mesh techniques in areas of moving surfaces.Turbulence was modeled with the k-e model.The results indicated that the developed models are suitable to analyze the water flows both in the chamber and in the turbine.For the turbine,the numerical results of pressure and torque were compared for the two cases.

关键词： wave energy Ansys CFX code Savonius rotor numerical simulation torque efficiency

Quantifying Roll Feel of a Car by Using a Musculoskeletal Mathematical Model

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Computer Modeling in Engineering & Sciences 2019年第3期118卷 493-507页

作者： Masaki Izawa Ryota Araki Tatsuro Suzuki Kaito Watanabe Kazuhito Misaji Showa Corporation 112-1 Haga-daiHaga-machHaga-gunTochigiJapan Ex-Graduate Student Nihon UniversityCollege of Industrial TechnologyDepartment of Mathematical Information EngineeringJapan Nihon University College of Industrial TechnologyDepartment of Mathematical Information EngineeringJapan

Primary purpose of this research is to create a three-dimensional musculoskeletal mathematical model of a driver of a car using a motion capture system.The model is then used in an analysis of drive torque around joints and attached muscles as a vehicle travels in different travel modes and damping force settings to examine‘burdens’for the driver.Previous studies proposed a method of quantifying the degree of musculoskeletal load in simple human motion from the changes in drive torque around joints and attached muscles.However,examination of the level of burdens for the driver while driving using this method does not seem to exist.Especially within the scope of evaluating different travel modes and dampers,there is no other study.Results of this study are hence a valuable new perspective on quantitative analysis of the burdens for the driver’s joints and muscles depending on the different settings of travel modes and dampers.

关键词： Human engineering biomechanics musculoskeletal mathematical model driving torque motion capture