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1 – 10 of over 2000
Article
Publication date: 6 November 2017

Kaiqiang Wang, Shejuan Xie, Hongwei Yuan, Cuixiang Pei, Zhenmao Chen and Weixin Li

In this paper, numerical modelling and dynamical response analysis were performed for the HL-2M vacuum vessel (VV) and shielding plates (SPs) during a plasma disruption by…

Abstract

Purpose

In this paper, numerical modelling and dynamical response analysis were performed for the HL-2M vacuum vessel (VV) and shielding plates (SPs) during a plasma disruption by using an updated ANSYS parametric design language (APDL) code developed by the authors. The purpose of this paper is to investigate the influence of the SPs on the dynamical response of VV owing to a transient electromagnetic (EM) force and to optimize the design of SPs in view of the minimization of the structural dynamic response.

Design/methodology/approach

The Lagrangian approach, i.e. the moving coordinate scheme developed by the authors, was updated to tackle the EM-mechanical coupling effect in the dynamic response analysis of the VV-SPs system due to the transient EM force during plasma disruptions. To optimize the structural design of HL-2M SPs, the influence of the key parameters of SPs, i.e., the side length, thickness and material properties, was clarified on the basis of the numerical results and an optimized design of SPs was obtained.

Findings

The updated APDL code of the Lagrangian approach is efficient for the transient dynamical response analysis of the VV-SPs system owing to the EM force. The SP of a smaller side length, larger thickness tungsten material better mitigates the dynamical response of the VV-SPs system.

Originality/value

The Lagrangian approach was updated for the EM–mechanical coupling dynamical response analysis of the VV-SPs system, and the influence of the SP parameters on the dynamical response of the VV-SPs system of HL-2M Tokamak was clarified.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 19 June 2007

Andrea Gaetano Chiariello, Giovanni Miano, Antonio Maffucci, Fabio Villone and Walter Zamboni

To investigate the possible application of carbon nanotubes (CNTs) as interconnects and antennas.

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Abstract

Purpose

To investigate the possible application of carbon nanotubes (CNTs) as interconnects and antennas.

Design/methodology/approach

An electromagnetic macroscopic modelling of CNT is derived. The conduction electrons of the nanotube are considered as a 2D fluid moving on the surface representing the positive ion lattice. The linearized Euler's equation describing the fluid motion is used as a macroscopic constitutive relationship to be coupled to Maxwell's equation. A surface integral formulation coupled to the fluid model is solved numerically using a finite element method. For peculiar configurations, transmission line‐like parameters of CNTs are derived.

Findings

Single wall CNT interconnects, due to the high resistance and characteristic impedance with respect to ideally scaled silicon technology, should be used in arrays and bundles.

Research limitations/implications

Only single wall CNTs are considered.

Originality/value

The paper present a novel approach to CNTs and provides a comparison among the behaviour of CNTs with respect to ideally‐scaled silicon technology.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 September 2022

Xuwen Chi, Cao Tan, Bo Li, Jiayu Lu, Chaofan Gu and Changzhong Fu

The purpose of this paper is to solve the common problems that traditional optimization methods cannot fully improve the performance of electromagnetic linear actuators (EMLAs).

Abstract

Purpose

The purpose of this paper is to solve the common problems that traditional optimization methods cannot fully improve the performance of electromagnetic linear actuators (EMLAs).

Design/methodology/approach

In this paper, a multidisciplinary optimization (MDO) method based on the non-dominated sorting genetic algorithm-II (NSGA-II) algorithm was proposed. An electromagnetic-mechanical coupled actuator analysis model of EMLAs was established, and the coupling relationship between static/dynamic performance of the actuator was analyzed. Suitable optimization variables were designed based on fuzzy grayscale theory to address the incompleteness of the actuator data and the uncertainty of the coupling relationship. A multiobjective genetic algorithm was used to obtain the optimal solution set of Pareto with the maximum electromagnetic force, electromagnetic force fluctuation rate, time constant and efficiency as the optimization objectives, the final optimization results were then obtained through a multicriteria decision-making method.

Findings

The experimental results show that the maximum electromagnetic force, electromagnetic force fluctuation rate, time constants and efficiency are improved by 18.1%, 38.5%, 8.5% and 12%, respectively. Compared with single-discipline optimization, the effectiveness of the multidiscipline optimization method was verified.

Originality/value

This paper proposes a MDO method for EMLAs that takes into account static/dynamic performance, the proposed method is also applicable to the design and analysis of various electromagnetic actuators.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 5 February 2018

Kaiyu Dai, Fangwei Xie, Qingsong Gao, Desheng Zhang, Erming Ding and Xinjian Guo

The purpose of this paper is to study the pressure response characteristics of the cartridge electromagnetic relief valve, which offers the problems caused by low pressure…

Abstract

Purpose

The purpose of this paper is to study the pressure response characteristics of the cartridge electromagnetic relief valve, which offers the problems caused by low pressure response and low efficiency in hydraulic plate shearing machines.

Design/methodology/approach

First of all the mathematical model of the cartridge electromagnetic relief valve is deduced to analyze the influence of the relevant parameters on the system pressure response. Then experiments are conducted to research the dynamic characteristics on building and relieving pressure. Through comparison of theoretical and experimental research, the results are found.

Findings

The results show that the input flow, working pressure, diameter of adjacent damping hole, and spring stiffness of the main valve have great influence on building pressure of the system, and have no influence on relieving pressure, while diameter of damping hole of control cover plate has influence on the building and relieving pressure of the system.

Originality/value

The research results provide powerful theoretical support for the parametric design of the cartridge electromagnetic relief valve in the hydraulic system of plate shearing machine.

Details

International Journal of Structural Integrity, vol. 9 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 20 March 2017

Yong Zhao, Jue Yu, Hao Wang, Genliang Chen and Xinmin Lai

This paper aims to propose an electromagnetic prismatic joint with variable stiffness. The joint can absorb the sudden shocks and improve the natural dynamics of robotics…

Abstract

Purpose

This paper aims to propose an electromagnetic prismatic joint with variable stiffness. The joint can absorb the sudden shocks and improve the natural dynamics of robotics. The ability of regulating the output stiffness can also be used for force control in industrial applications.

Design/methodology/approach

Unlike some existing designs of variable stiffness joints (VSJs) in which the stiffness regulation is implemented using the stiffness adjustment motor and mechanisms, the main structure of the electromagnetic VSJ is a permanent magnet (PM) arranged inside coaxial cylinder coils. The adjustment of input current can cause the change of magnetic force between the PM and the cylinder coils, and thus leads to the variation of output stiffness.

Findings

According to the theoretical model, the output stiffness of the electromagnetic VSJ is linearly proportional to the input current. The experiments further indicate that the current-controlled stiffness can make the stiffness variation response of this VSJ more rapid for practical applications. Due to the large damping introduced by the copper-based self-lubrication bearings, the VSJ shows good properties in motion positioning and trajectory tracking.

Originality/value

In summary, the electromagnetic VSJ is compact in size and light in weight. It is possible to realize the online adaptability to work conditions with dynamic load by using this VSJ.

Details

Industrial Robot: An International Journal, vol. 44 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 13 November 2020

Y.S. Wang, H. Guo, Tao Yuan, L.F. Ma and Changcheng Wang

Electromagnetic noise of permanent magnet synchronous motor (PMSM) seriously affects the sound quality of electric vehicles (EVs). This paper aims to present a…

Abstract

Purpose

Electromagnetic noise of permanent magnet synchronous motor (PMSM) seriously affects the sound quality of electric vehicles (EVs). This paper aims to present a comprehensive process for the electromagnetic noise analysis and optimization of a water-cooled PMSM.

Design/methodology/approach

First, the noises of an eight-pole 48-slot PMSM in at speeds up to 10,000 rpm are measured. Furthermore, an electromagnetic-structural-acoustic model of the PMSM is established for multi-field coupling simulations of electromagnetic noises. Finally, the electromagnetic noise of the PMSM is optimized by using the multi-objective genetic algorithm, where a multi-objective function related to the slot width of PMSM stator is defined for radial electromagnetic force (REF) optimization.

Findings

The experimental results show that main electromagnetic noises are the 8n-order (n = 1, 2, 3, …) and 12-order noises. The simulated results show that the REFs are mainly generated by the 8n-order (n = 1, 2, 3, 4, 5, 6) vibrations, especially those of the 8th, 16th, 24th and 32th orders. The 12-order noise is a mechanical noise, which might be caused by the bearings and other structures of the PMSM. Comparing the simulated results before and after optimization, both the REFs and electromagnetic noises are effectively reduced, which suggests that an appropriate design of stator slot is important for reducing electromagnetic noise of the PMSM.

Originality/value

In view of applications, the methods proposed in this paper can be applied to other types of PMSM for generation mechanism analysis of electromagnetic noise, optimal design of PMSM and thereby noise improvement of EVs.

Article
Publication date: 9 August 2011

Oleg Rybin, Konstantin Yemelyanov and Tahira Nawaz

The purpose of this paper is to obtain the long‐wave approximations for the effective electromagnetic response of two‐dimensional sandwich composite structure, as infinite…

Abstract

Purpose

The purpose of this paper is to obtain the long‐wave approximations for the effective electromagnetic response of two‐dimensional sandwich composite structure, as infinite chain of infinitely long metal cylinders symmetrically immersed in an infinite metamaterial slab are obtained. The slab is an infinite magneto‐dielectric matrix with periodically imbedded infinitely long metal cylinders whose diameter is smaller than those of the chain cylinders. The case of ferrite‐like metallic saturated inclusions is considered in the study.

Design/methodology/approach

The result is presented as a generalized expression of the electromagnetic response of the infinite periodic chain of infinitely long metallic cylinders immersed into the flat magneto‐dielectric host medium. Those expressions were obtained utilizing S‐ and T‐matrices approaches.

Findings

A good coincidence between the results of analytical modeling and numerical simulations was found.

Research limitations/implications

Low values of the metal volume fraction; microwave frequency range.

Practical implications

An improving of directivity of patch antennas; a minimization of patch antennas.

Originality/value

The analytical characterization of new artificial substrate‐like structure to be utilized for designing patch antennas of a new generation.

Details

Multidiscipline Modeling in Materials and Structures, vol. 7 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 6 March 2017

Cheng-Chi Tai, Wei-Cheng Wang and Yuan-Jui Hsu

This study aims to establish a dynamic process model of an electromagnetic thermotherapy system (ETS) to predict the temperature of a thermotherapy needle.

Abstract

Purpose

This study aims to establish a dynamic process model of an electromagnetic thermotherapy system (ETS) to predict the temperature of a thermotherapy needle.

Design/methodology/approach

The model is used for real-time predicting the static and dynamic responses of temperature and can therefore provide a valuable analysis for system monitoring.

Findings

The electromagnetic thermotherapy process is a nonlinear problem in which the system identification is implemented by a neural network identifier. It can simulate the input/output relationship of a real system with an excellent approximation ability to uncertain nonlinear system. A system identifier for an ETS is analyzed and selected with recurrent neural networks models to deal with various treatment processes.

Originality/value

The Elman neural network (ENN) prediction model on ETS proposed in this study is an easy and feasible method. Comparing two situations of inputs with more and fewer data, both are trained to present low mean squared error, and the temperature response error appears within 15 per cent. The ENN, with the advantages of simple design and stable efficacy, is useful for establishing the temperature prediction model to ensure the security in the thermotherapy.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 28 October 2014

Richard Tarparelli, Renato Iovine, Luigi La Spada and Lucio Vegni

– The purpose of this paper is to contribute an analytical and numerical study of a new type of nanoshell particles operating in the visible regime.

Abstract

Purpose

The purpose of this paper is to contribute an analytical and numerical study of a new type of nanoshell particles operating in the visible regime.

Design/methodology/approach

The structure consists of a core/shell particle, arranged in a planar array configuration, with a polymethyl methacrylate (PMMA)-graphene core and gold thin shell.

Findings

By exploiting the proposed analytical model the design of a metamaterial-based sensor, operating in the optical frequency range, for the detection of tissue diseases is shown.

Originality/value

Full-wave simulations confirm the capability of the proposed sensor to identify different compounds by refractive index measurement.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 33 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 9 November 2012

Redha Benachour, Saïda Latreche, Mohamed El Hadi Latreche and Christian Gontrand

The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.

Abstract

Purpose

The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.

Design/methodology/approach

The nonlinear average model is used in power electronic integration design as a behavioral model, where it is applied to a voltage source inverter based on IGBTs. This model was chosen because it takes into account the nonlinearity of the power semiconductor components and the wiring circuit effects, which can be formalized by the virtual delay concept. In addition, the nonlinear average model cannot distinguish between slow and quick variables and this is an important feature of the model convergence.

Findings

The paper studies extensively the construction of the nonlinear average model algorithm theoretically. Detailed explanations of the application of this model to voltage source inverter design are provided. The study demonstrates how this model illustrates the effect of the nonlinearity of the power semiconductor components' characteristics on dynamic electrical quantities. It also predicts the effects due to wiring in the inverter circuit.

Research limitations/implications

More simulations and experimental analysis are still necessary to improve the model's accuracy, by using other static characteristic approaches, and to validate the applicability of the model to different converter topologies.

Practical implications

The paper formulates a simple nonlinear average model algorithm, discussing each step. This model was described by VHDL‐AMS. On the one hand, it will assist theoretical and practical research on different topologies of power electronic converters, particularly in power integration systems design such as the integrated power electronics modules (IPEM). On the other hand, it will give designers a more precise behavioral model with a simpler design process.

Originality/value

The nonlinear average model used in power electronic integration design as behavioral model is a novel approach. This model reduces computational costs significantly, takes physical effects into account and is easy to implement.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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