Dynamic characteristics of three-degree-of-freedom resonant actuator

Purpose Linear oscillatory actuators have been used in a wide range of applications because they have a lot of advantages. Additionally, multi-degree of freedom resonant actuators have been developed. The purpose of this paper is to propose a novel three-degree-of-freedom resonant actuator resonant actuator that is driven in three directions. The dynamic characteristics are clarified through finite element analysis and measurement. Design/methodology/approach A novel three-degree-of-freedom resonant actuator resonant actuator consists of a cross-shaped mover, a stator and five excitation coils. The magnetic structure of this actuator is geometrically similar to that of general permanent magnet synchronous motor. Therefore, vector control is applied to this actuator. The dynamic characteristics are analyzed and measured. Findings Computed results show that the proposed actuator is able to be independently driven in three directions. However, measured result show that mutual interference is severely observed because of the structure of the mover support mechanism. Therefore, the structure needs to be improved. Originality/value The proposed actuator has originality in its structure and operating principle.

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Analysis of the rotor dynamics characteristics of multi-degree-of-freedom permanent magnet synchronous motor

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/1461348419830211 ◽

2019 ◽

Vol 38 (2) ◽

pp. 352-362 ◽

Cited By ~ 2

Author(s):

Zheng Li ◽

Qiushuo Chen ◽

Feihong Yue ◽

Qunjing Wang

Keyword(s):

Finite Element ◽

Permanent Magnet ◽

Critical Speed ◽

Permanent Magnet Synchronous Motor ◽

Synchronous Motor ◽

Degree Of Freedom ◽

Normal Operation ◽

Element Analysis ◽

Pass Through ◽

The Relationship

The spherical shell rotor is contained in the multi-degree-of-freedom permanent magnet synchronous motor. When the rated speed of motor is close to the critical speed, the motor will generate multiple resonances, which will affect the normal operation of the motor. The motor rotor must pass through the first-order critical speed and work at the safety range between 1-order and 2-order critical speed. According to the dynamic characteristics of rotor system, a mathematical model of rotor under free state is established, and the result between finite element and analytical methods is comparison. The influence of rotor gyroscope effect on critical speed is analyzed, and the finite element analysis of whether the rigidity of rotor material affects the critical speed is also carried out. The relationship between bending modal and deformation displacement is tested under different rigidity conditions and the stator deformation caused by rotor rotation is analyzed when the stator is filled with different liquids. The relationship between the rotational speed and the amplitude of the spherical rotor is verified by experiments, and the corresponding rules are summarized. The results of the simulation and analysis are referenced by the optimal design of motor.

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Analysis of Magnetic Field and Torque Features of Improved Permanent Magnet Rotor Deflection Type Three-Degree-of-Freedom Motor

Energies ◽

10.3390/en13102533 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2533 ◽

Cited By ~ 1

Author(s):

Zheng Li ◽

Xuze Yu ◽

Zengtao Xue ◽

Hexu Sun

Keyword(s):

Magnetic Field ◽

Permanent Magnet ◽

Degree Of Freedom ◽

Structure Stability ◽

Permanent Magnet Motor ◽

Element Analysis ◽

Radial Flux ◽

Three Phase ◽

Before And After ◽

Three Degree Of Freedom

This paper proposes a novel layered permanent magnet motor (N-LPM), which is based on a three-degree-of-freedom (3-DOF) permanent magnet motor. Compared with the former, the improved N-LPM air gap magnetic density, torque and structure stability have been significantly improved. The proposed N-LPM has three layers of stator along the axis direction, and each layer of stator has three-phase winding. In order to calculate the magnetic field and torque distribution of the N-LPM, an analytical method (AM) is proposed. For performance verification and accurate calculation, finite-element analysis (FEA) is adopted. The two kinds of motors before and after the improvement are compared, and their magnetic field, torque and stability are analyzed. The optimization rate is defined to evaluate the performance of the motor before and after improvement. The results show that the radial flux density, rotation torque, deflection torque and the volume optimization rate of the permanent magnet of the improved motor are 80%, 25%, 50% and 54.72% respectively, and the comprehensive performance is improved significantly.

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Usage of FEM for synthesis of dead-beat current controller for permanent magnet synchronous motor

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-12-2018-0534 ◽

2019 ◽

Vol 38 (5) ◽

pp. 1386-1400 ◽

Cited By ~ 1

Author(s):

Ryszard Palka ◽

Rafal Piotuch

Keyword(s):

Permanent Magnet ◽

Permanent Magnet Synchronous Motor ◽

Permanent Magnet Synchronous Motors ◽

Element Analysis ◽

Content Type ◽

Control Quality ◽

Current Controller ◽

Transient Simulations ◽

Self Tuning ◽

Electro Magnetic

Purpose Predictive controllers and permanent magnet synchronous motors (PMSMs) got more attention over the past decades thanks to their applicable features. This paper aims to propose and verify a method to design a predictive current controller with consideration of motor characteristics obtained from finite element analysis (FEA). Design/methodology/approach Permanent magnet motor parameters and its maps can be calculated by means of FEA. The model takes into account magnetic saturation and thermal electro-magnetic properties. For each dq current vector and each position, self and mutual inductances are calculated. Based on co-energy method and fundamentals of coordinate transformation dynamic and static, dq inductances are obtained. These are used in classical and modified dead-beat current controller equations. Findings To sustain good features of a controller over higher current regions, it is necessary to adapt control law of a dead-beat controller. After its modification, control quality can be superior over classical solution in high saturation regions. The transient simulations of controller and motor give accurate results. Originality/value Common predictive current controllers use nominal motor parameters in their equations. The authors proposed a modified dead-beat current controller to improve the control quality. There is no need to apply self-tuning algorithms, and implementation of the controller is not much more complicated than that of the classical controller. Designer of a control system can obtain required data from motor designer; in design process of modern machines such data are often already available. The proposed methodology increases control quality of the presented dead-beat controller.

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A three-degree-of-freedom hybrid vibration isolation system using adaptive proportional control supported by passive weight support mechanism

10.1117/12.2036172 ◽

2013 ◽

Author(s):

Yun-Hui Liu ◽

Wei-Hao Wu ◽

Chih-Liang Chu

Keyword(s):

Vibration Isolation ◽

Degree Of Freedom ◽

Isolation System ◽

Vibration Isolation System ◽

Proportional Control ◽

Support Mechanism ◽

Weight Support ◽

Three Degree Of Freedom

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Miniaturization Consideration of a Three-Degree-of-Freedom Linear Oscillatory Actuator for Haptic Device Integrated with Support Mechanism

Journal of the Japan Society of Applied Electromagnetics and Mechanics ◽

10.14243/jsaem.29.408 ◽

2021 ◽

Vol 29 (2) ◽

pp. 408-413

Author(s):

Ryosuke NAKAMURA ◽

Akira HEYA ◽

Katsuhiro HIRATA

Keyword(s):

Degree Of Freedom ◽

Haptic Device ◽

Support Mechanism ◽

Three Degree Of Freedom

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Torque Ripple Minimization of the Permanent Magnet Synchronous Machine by Modulation of the Phase Currents

Sensors ◽

10.3390/s20082406 ◽

2020 ◽

Vol 20 (8) ◽

pp. 2406 ◽

Cited By ~ 1

Author(s):

Cezary Jędryczka ◽

Dawid Danielczyk ◽

Wojciech Szeląg

Keyword(s):

Permanent Magnet ◽

Permanent Magnets ◽

Numerical Models ◽

Permanent Magnet Synchronous Motor ◽

Torque Ripple ◽

Minimization Method ◽

Element Analysis ◽

Current Harmonics ◽

Wide Range ◽

Zero Sequence

This paper deals with the torque ripple minimization method based on the modulation of the phase currents of the permanent-magnet synchronous motor (PMSM) drive. The shape of the supply current waveforms reducing the torque ripple of the machine considered was determined on the basis of finite element analysis (FEA). In the proposed approach, the machine is supplied by a six-leg inverter in order to allow for the injection of zero sequence current harmonics. Two test PMSMs with fractional-slot concentrated windings (FSCW) and surface-mounted permanent magnets (SPMs) have been examined as a case study problem. Wide-range fractional analyses were performed using developed numerical models of the electromagnetic field distribution in the considered machines. The results obtained show that the level of torque ripple in FSCW PMSMs can be effectively reduced by the modulation of the phase currents under the six-leg inverter supply.

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Multidomain Topology Optimization for Crashworthiness Based on Hybrid Cellular Automata

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.486.250 ◽

2011 ◽

Vol 486 ◽

pp. 250-253 ◽

Cited By ~ 3

Author(s):

Lian Shui Guo ◽

Jun Huang ◽

Andres Tavor ◽

John E. Renaud

Keyword(s):

Topology Optimization ◽

Element Analysis ◽

Design Problems ◽

Practical Applications ◽

Control Rules ◽

Engineering Design Problems ◽

Wide Range ◽

Result Show ◽

Update Rules ◽

Structure Result

This research introduces a multidomain topology optimization algorithm for crashworthy structure undergoing large deformations. This technique makes use of the hybrid cellular automaton framework, which combines transient, non-linear finite-element analysis and local control rules acting on cells. The set of all cells defines the multidomains. Each subdomain has been defined by different material update rules according to specify constraint, and optimization iteration of each subdomain has been converged respectively during the optimal design process. The effectiveness of this technique is demonstrated through the design of a bumper-like structure. Result show that the new algorithm is suitable for practical applications. The case study presented demonstrates the potential significance of this work for a wide range of engineering design problems.

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Influence of micro-scale velocity slip on the dynamic characteristics of aerostatic slider

Industrial Lubrication and Tribology ◽

10.1108/ilt-02-2020-0059 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Dongju Chen ◽

Shuai Kong ◽

Jingfang Liu ◽

Jinwei Fan

Keyword(s):

Peer Review ◽

Dynamic Characteristics ◽

Velocity Slip ◽

Analysis Method ◽

Element Analysis ◽

Fluid Equation ◽

Content Type ◽

First Order ◽

Static Performance ◽

Simulation And Experiment

Purpose The purpose of this paper is to propose the pressure fluctuation to further evaluate and predict the dynamic and static characteristics of the aerostatic slider and improve the calculation accuracy of the aerostatic slider. Design/methodology/approach First-order velocity slip is introduced into the traditional gas-film fluid equation, and the numerical analysis method is used to solve the static performance of the aerostatic slider. The finite element analysis method is used to solve its dynamic characteristics. Findings It can be concluded from the simulation and experimental results that the model considering the velocity slip in the gas film flow is more accurate. The errors between the modal detection results and the vibration detection results (0.8%–5.8%) under speed slip are smaller than the traditional cases (23.7%–210%), which also verifies the correctness of the above conclusions. Originality/value In this paper, the method of simulation and experiment is used to prove that the first-order velocity slip model is more suitable to predict the dynamic response of the aerostatic slider than the condition without slip. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2020-0059/

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Effect of shape imperfections on elastic stresses of U-bends subjected to in-plane moment

International Journal of Structural Integrity ◽

10.1108/ijsi-01-2020-0012 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

L.A. Krishna ◽

A.R. Veerappan ◽

S. Shanmugam

Keyword(s):

Finite Element ◽

Structural Integrity ◽

Elastic Stress ◽

Circular Cross Section ◽

Bending Stress ◽

Membrane Stress ◽

Element Analysis ◽

Content Type ◽

Wide Range ◽

Stress Components

PurposePrecise assessment of elastic stress is required in the field of fracture mechanics. While bending a straight pipe, the deformation of the circular cross section out of roundness called ovality and thinning are foreseeable. The ovality has a significant effect on the structural integrity of the pipe. The sole objective of this paper is to provide new analytical solutions to predict accurate elastic stress distribution at the median section of the U-bend, with deformities such as ovality and thinning when subjected to in-plane closing moment by using elastic finite element analysis.Design/methodology/approachThe quarter model of the U bend has been analysed by using ABAQUS. The elastic stress components included in this analysis are longitudinal bending stress, longitudinal membrane stress, circumferential bending stress and circumferential membrane stress. Based on finite element results, analytical elastic stress solutions are also provided for both longitudinal and circumferential stresses by using these stress components.FindingsAs the ovality has a significant effect, it is further included in the analytical solution. The thinning is not included since it has very little effect. Analytical stress solutions are provided for a wide range of bend characteristics to include ovality, mean radius and thickness.Originality/valueSignificance of ovality and thinning on elastic stress of U-bend has not been reported in the existing literature.

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