The Experts below are selected from a list of 46530 Experts worldwide ranked by ideXlab platform

Kenji Endo - One of the best experts on this subject based on the ideXlab platform.

  • sensorless torque control of salient pole synchronous motor at zero speed operation
    IEEE Transactions on Power Electronics, 1999
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control using the counter electromotive force of a permanent-magnet motor (PM) debases the control performance at a low speed. We propose a Controllable System at full speed, including a zero speed using saliency. At low speed, the sensorless control is made by observing a current ripple at a time when alternating voltage has been applied to a salient-pole motor. Also, for discriminating the S and N poles of the magnet, magnetic saturation is used. A device has been applied to the motor rotor to allow the magnetic saturation to come about easily. Furthermore, at a time of high speed, drive at a full-speed range has been accomplished by switching smoothly over to a sensorless driving System making use of counter electromotive force. All algorithms are implemented by software, and this System can operate successively from starting to high-speed operation. The paper discusses the operational principles at a low speed, analysis and experimental results, the control scheme, how to changeover the control mode at high speed, and the experimental results.

  • sensor less torque control of salient pole synchronous motor at zero speed operation
    Applied Power Electronics Conference, 1997
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control scheme using the counter EMF of PM motors debases the control performance at low speed. Here, the authors propose a Controllable System at full speed, including zero speed, using saliency. At low speed, sensorless control is performed by observing a current ripple at a time when an alternating voltage has been applied to the salient-pole motor. Also, for discriminating the S and N poles of the magnet, magnetic saturation is used. A device has been applied to the motor rotor to allow the magnetic saturation to be brought about easily. Further, at times of high speed, a full speed range drive has been accomplished by switching smoothly over to a sensorless driving System, making use of the counter EMF.

C G L Bottcher - One of the best experts on this subject based on the ideXlab platform.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    Nature Physics, 2018
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor–insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial because many experiments exhibit a metallic regime with saturating low-temperature resistance, which is at odds with conventional theory. Here, we explore this transition in a highly Controllable System, a semiconductor heterostructure with epitaxial aluminium, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic and insulating behaviour, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor–insulator transition; it also improves the scaling behaviour while strongly altering the scaling exponent.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    arXiv: Mesoscale and Nanoscale Physics, 2017
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor-insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial, however, because many experiments exhibit a metallic regime with saturating low-temperature resistance, at odds with conventional theory. Here, we explore this transition in a novel, highly Controllable System, a semiconductor heterostructure with epitaxial Al, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic, and insulating behavior, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor-insulator transition, and improves scaling, while strongly altering the scaling exponent.

Takashi Aihara - One of the best experts on this subject based on the ideXlab platform.

  • sensorless torque control of salient pole synchronous motor at zero speed operation
    IEEE Transactions on Power Electronics, 1999
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control using the counter electromotive force of a permanent-magnet motor (PM) debases the control performance at a low speed. We propose a Controllable System at full speed, including a zero speed using saliency. At low speed, the sensorless control is made by observing a current ripple at a time when alternating voltage has been applied to a salient-pole motor. Also, for discriminating the S and N poles of the magnet, magnetic saturation is used. A device has been applied to the motor rotor to allow the magnetic saturation to come about easily. Furthermore, at a time of high speed, drive at a full-speed range has been accomplished by switching smoothly over to a sensorless driving System making use of counter electromotive force. All algorithms are implemented by software, and this System can operate successively from starting to high-speed operation. The paper discusses the operational principles at a low speed, analysis and experimental results, the control scheme, how to changeover the control mode at high speed, and the experimental results.

  • sensor less torque control of salient pole synchronous motor at zero speed operation
    Applied Power Electronics Conference, 1997
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control scheme using the counter EMF of PM motors debases the control performance at low speed. Here, the authors propose a Controllable System at full speed, including zero speed, using saliency. At low speed, sensorless control is performed by observing a current ripple at a time when an alternating voltage has been applied to the salient-pole motor. Also, for discriminating the S and N poles of the magnet, magnetic saturation is used. A device has been applied to the motor rotor to allow the magnetic saturation to be brought about easily. Further, at times of high speed, a full speed range drive has been accomplished by switching smoothly over to a sensorless driving System, making use of the counter EMF.

C M Marcus - One of the best experts on this subject based on the ideXlab platform.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    Nature Physics, 2018
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor–insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial because many experiments exhibit a metallic regime with saturating low-temperature resistance, which is at odds with conventional theory. Here, we explore this transition in a highly Controllable System, a semiconductor heterostructure with epitaxial aluminium, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic and insulating behaviour, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor–insulator transition; it also improves the scaling behaviour while strongly altering the scaling exponent.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    arXiv: Mesoscale and Nanoscale Physics, 2017
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor-insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial, however, because many experiments exhibit a metallic regime with saturating low-temperature resistance, at odds with conventional theory. Here, we explore this transition in a novel, highly Controllable System, a semiconductor heterostructure with epitaxial Al, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic, and insulating behavior, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor-insulator transition, and improves scaling, while strongly altering the scaling exponent.

Morten Kjaergaard - One of the best experts on this subject based on the ideXlab platform.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    Nature Physics, 2018
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor–insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial because many experiments exhibit a metallic regime with saturating low-temperature resistance, which is at odds with conventional theory. Here, we explore this transition in a highly Controllable System, a semiconductor heterostructure with epitaxial aluminium, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic and insulating behaviour, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor–insulator transition; it also improves the scaling behaviour while strongly altering the scaling exponent.

  • superconducting insulating and anomalous metallic regimes in a gated two dimensional semiconductor superconductor array
    arXiv: Mesoscale and Nanoscale Physics, 2017
    Co-Authors: C G L Bottcher, Fabrizio Nichele, Morten Kjaergaard, Henri J Suominen, Javad Shabani, C J Palmstrom, C M Marcus
    Abstract:

    The superconductor-insulator transition in two dimensions has been widely investigated as a paradigmatic quantum phase transition. The topic remains controversial, however, because many experiments exhibit a metallic regime with saturating low-temperature resistance, at odds with conventional theory. Here, we explore this transition in a novel, highly Controllable System, a semiconductor heterostructure with epitaxial Al, patterned to form a regular array of superconducting islands connected by a gateable quantum well. Spanning nine orders of magnitude in resistance, the System exhibits regimes of superconducting, metallic, and insulating behavior, along with signatures of flux commensurability and vortex penetration. An in-plane magnetic field eliminates the metallic regime, restoring the direct superconductor-insulator transition, and improves scaling, while strongly altering the scaling exponent.