The Experts below are selected from a list of 47400 Experts worldwide ranked by ideXlab platform

Denver Maharaj - One of the best experts on this subject based on the ideXlab platform.

  • composite electromagnetic interference shielding materials for Aerospace Applications
    Composite Structures, 2009
    Co-Authors: Christopher J Von Klemperer, Denver Maharaj
    Abstract:

    Electromagnetic interference (EMI) occurs when electronic devices are subject to electromagnetic radiation from unwanted sources at the same frequency ranges that these devices operate. Metals typically serve as excellent EMI shielding agents, but their heavy weight, high cost and susceptibility to forms of environmental degradation make them an undesired choice for many current electronic devices. Conversely fibre reinforced polymeric (FRP) composite materials are normally light weight, and can be cheaper to produce, but typically lack the inherent EMI shielding capabilities that may be required. This research work addresses the viability FRP composite materials for use as EMI shielding structures, specifically for Aerospace Applications. It was found that carbon fibre could suffice this purpose, but likely required filler materials to enhance electrical conductivity and shielding effectiveness (SE).

  • composite electromagnetic interference shielding materials for Aerospace Applications
    Composite Structures, 2009
    Co-Authors: Christopher J Von Klemperer, Denver Maharaj
    Abstract:

    Electromagnetic interference (EMI) occurs when electronic devices are subject to electromagnetic radiation from unwanted sources at the same frequency ranges that these devices operate. Metals typically serve as excellent EMI shielding agents, but their heavy weight, high cost and susceptibility to forms of environmental degradation make them an undesired choice for many current electronic devices. Conversely fibre reinforced polymeric (FRP) composite materials are normally light weight, and can be cheaper to produce, but typically lack the inherent EMI shielding capabilities that may be required. This research work addresses the viability FRP composite materials for use as EMI shielding structures, specifically for Aerospace Applications. It was found that carbon fibre could suffice this purpose, but likely required filler materials to enhance electrical conductivity and shielding effectiveness (SE).

Wen Jiang - One of the best experts on this subject based on the ideXlab platform.

  • electric drive system of dual winding fault tolerant permanent magnet motor for Aerospace Applications
    IEEE Transactions on Industrial Electronics, 2015
    Co-Authors: Xuefeng Jiang, Zhenyang Hao, Ruiwu Cao, Wenxin Huang, Wen Jiang
    Abstract:

    In this paper, a new electric drive system based on a six-phase ten-pole dual-winding fault-tolerant permanent-magnet (DFPM) motor for Aerospace Applications is proposed and investigated. The proposed DFPM motor consists of optimal surface-mounted permanent-magnet (PM) rotor and 12-slot stator with two sets of independent three-phase concentrated armature windings on alternate teeth, which incorporates the merits of high power density and high efficiency of the PM motor and high fault tolerance of the dual-winding motor. To achieve the fault-tolerant performance of the electric drive system, the redundant fault-tolerant control strategy based on the failure diagnosis and redundancy communication is proposed and applied to the electric drive system. Then, the operational performance of the drive system under open-circuit and short-circuit fault has been verified by simulation and experiments. The research results show that the open-circuit and short-circuit fault can be detected immediately and the output performance of the DFPM motor under fault conditions is almost the same as the normal condition, which verified the proposed electric drive system, DFPM motor, and fault-tolerant control strategy.

  • Analysis of a dual-winding fault-tolerant permanent magnet machine drive for Aerospace Applications
    2015 IEEE International Magnetics Conference (INTERMAG), 2015
    Co-Authors: Xuefeng Jiang, Wenxin Huang, C. Li, Wen Jiang
    Abstract:

    With the increasing development of aircraft and helicopter, new electric drive system for Aerospace Applications have attracted more and more attentions in the aviation sector [1]-[2]. The common hydraulic drive helicopter winch is replaced by the electric drive helicopter winch gradually, due to the fact that the electric drive system can not only improve the system efficiency and the flexibility of variable speed control, but also reduce the weight and volume of the system [2]-[3]. However, in the electric drive helicopter winch systems, where continuous operation must be ensured, high reliability and strong fault tolerance become a critical requirement [2]-[4]. The purpose of this paper is to propose a new electric drive helicopter winch system based on a six-phase ten-pole dual-winding fault-tolerant permanent magnet (DFPM) machine. The DFPM machine, which incorporates the merits of high power density and high efficiency of permanent magnet (PM) machine and high fault-tolerance of dual-winding machine, consists of optimal surface-mounted permanent magnet rotor and 12 slots stator with two sets of independent three-phase concentrated armature windings on alternate teeth. To achieve the fault-tolerant performance, the redundant fault-tolerant control strategy based on speed, current, voltage three-loop control is proposed and analyzed. Then, the electromagnetic performances of the DFPM machine drive with an open-circuit fault under load hoisting and dropping conditions have been verified by experiments. The research results showing the effectiveness of the proposed fault-tolerant control strategy and the high performance of the fault-tolerant characteristic of the proposed DFPM machine drive.

Manabu Nakai - One of the best experts on this subject based on the ideXlab platform.

  • new aspect of development of high strength aluminum alloys for Aerospace Applications
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2000
    Co-Authors: Manabu Nakai
    Abstract:

    Abstract New aspect of developing the materials in lights of interrelationship among alloy/process microstructure (mainly the second phase particles) — properties combined with micromechanics has been carried out in 2024 aluminum alloys. The fracture toughness is proportional to the square root of the spacing of constituents, Cu 2 FeAl 7 , in 2024 aluminum alloys. Broadening the spacing 75–140 μm, the fracture toughness increases by 20%. In a low Δ K region, the fatigue cracks propagate much slowly by broadening the spacing of dispersoids, Cu 2 Mn 3 Al 20 . Broadening the spacing, the crack propagation rate decreases by 50%. The larger size of dispersoids, Cu 2 Mn 3 Al 20 , makes the rate much slower than smaller ones, Cr 2 Mg 3 Al 18 or ZrAl 3 . On the other hand, in a high Δ K region, the rate becomes slower mainly by broadening the constituents spacing. The newly developed 2×24 aluminum alloy sheets, in these concepts in mind, have excellent fracture toughness and fatigue crack propagation characteristics to provide lower weight, higher damage tolerance, and longer-term durability for Aerospace Applications.

Xuefeng Jiang - One of the best experts on this subject based on the ideXlab platform.

  • electric drive system of dual winding fault tolerant permanent magnet motor for Aerospace Applications
    IEEE Transactions on Industrial Electronics, 2015
    Co-Authors: Xuefeng Jiang, Zhenyang Hao, Ruiwu Cao, Wenxin Huang, Wen Jiang
    Abstract:

    In this paper, a new electric drive system based on a six-phase ten-pole dual-winding fault-tolerant permanent-magnet (DFPM) motor for Aerospace Applications is proposed and investigated. The proposed DFPM motor consists of optimal surface-mounted permanent-magnet (PM) rotor and 12-slot stator with two sets of independent three-phase concentrated armature windings on alternate teeth, which incorporates the merits of high power density and high efficiency of the PM motor and high fault tolerance of the dual-winding motor. To achieve the fault-tolerant performance of the electric drive system, the redundant fault-tolerant control strategy based on the failure diagnosis and redundancy communication is proposed and applied to the electric drive system. Then, the operational performance of the drive system under open-circuit and short-circuit fault has been verified by simulation and experiments. The research results show that the open-circuit and short-circuit fault can be detected immediately and the output performance of the DFPM motor under fault conditions is almost the same as the normal condition, which verified the proposed electric drive system, DFPM motor, and fault-tolerant control strategy.

  • Analysis of a dual-winding fault-tolerant permanent magnet machine drive for Aerospace Applications
    2015 IEEE International Magnetics Conference (INTERMAG), 2015
    Co-Authors: Xuefeng Jiang, Wenxin Huang, C. Li, Wen Jiang
    Abstract:

    With the increasing development of aircraft and helicopter, new electric drive system for Aerospace Applications have attracted more and more attentions in the aviation sector [1]-[2]. The common hydraulic drive helicopter winch is replaced by the electric drive helicopter winch gradually, due to the fact that the electric drive system can not only improve the system efficiency and the flexibility of variable speed control, but also reduce the weight and volume of the system [2]-[3]. However, in the electric drive helicopter winch systems, where continuous operation must be ensured, high reliability and strong fault tolerance become a critical requirement [2]-[4]. The purpose of this paper is to propose a new electric drive helicopter winch system based on a six-phase ten-pole dual-winding fault-tolerant permanent magnet (DFPM) machine. The DFPM machine, which incorporates the merits of high power density and high efficiency of permanent magnet (PM) machine and high fault-tolerance of dual-winding machine, consists of optimal surface-mounted permanent magnet rotor and 12 slots stator with two sets of independent three-phase concentrated armature windings on alternate teeth. To achieve the fault-tolerant performance, the redundant fault-tolerant control strategy based on speed, current, voltage three-loop control is proposed and analyzed. Then, the electromagnetic performances of the DFPM machine drive with an open-circuit fault under load hoisting and dropping conditions have been verified by experiments. The research results showing the effectiveness of the proposed fault-tolerant control strategy and the high performance of the fault-tolerant characteristic of the proposed DFPM machine drive.

Christopher J Von Klemperer - One of the best experts on this subject based on the ideXlab platform.

  • composite electromagnetic interference shielding materials for Aerospace Applications
    Composite Structures, 2009
    Co-Authors: Christopher J Von Klemperer, Denver Maharaj
    Abstract:

    Electromagnetic interference (EMI) occurs when electronic devices are subject to electromagnetic radiation from unwanted sources at the same frequency ranges that these devices operate. Metals typically serve as excellent EMI shielding agents, but their heavy weight, high cost and susceptibility to forms of environmental degradation make them an undesired choice for many current electronic devices. Conversely fibre reinforced polymeric (FRP) composite materials are normally light weight, and can be cheaper to produce, but typically lack the inherent EMI shielding capabilities that may be required. This research work addresses the viability FRP composite materials for use as EMI shielding structures, specifically for Aerospace Applications. It was found that carbon fibre could suffice this purpose, but likely required filler materials to enhance electrical conductivity and shielding effectiveness (SE).