Patents by Inventor Hiroyuki KITAZWA

Hiroyuki KITAZWA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Aircraft motor drive control apparatus and aircraft motor drive control system
    Patent number: 8558501
    Abstract: The command signal processing unit outputs, when a first PWM frequency command signal is received, a high-PWM frequency command signal such that an asynchronous PWM control is performed at a PWM frequency of a predetermined constant frequency. The command signal processing unit outputs, when a second PWM frequency command signal is received, a low-PWM frequency command signal such that an asynchronous or synchronous PWM control is performed at a frequency lower than the above-described frequency. The PWM frequency control unit controls the PWM frequency such that an asynchronous PWM control is performed if a motor has a rotational speed less than a predetermined rotational speed and that a synchronous PWM control is performed if the motor has a rotational speed greater than or equal to the predetermined rotational speed, when a low-PWM frequency command signal is input.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: October 15, 2013
    Assignee: Nabtesco Corporation
    Inventors: Tokuji Tsunematsu, Kazushige Nakajima, Hiroyuki Kitazwa, Tomoyuki Yokogawa
  • AIRCRAFT MOTOR DRIVE CONTROL APPARATUS AND AIRCRAFT MOTOR DRIVE CONTROL SYSTEM
    Publication number: 20120187892
    Abstract: The command signal processing unit outputs, when a first PWM frequency command signal is received, a high-PWM frequency command signal such that an asynchronous PWM control is performed at a PWM frequency of a predetermined constant frequency. The command signal processing unit outputs, when a second PWM frequency command signal is received, a low-PWM frequency command signal such that an asynchronous or synchronous PWM control is performed at a frequency lower than the above-described frequency. The PWM frequency control unit controls the PWM frequency such that an asynchronous PWM control is performed if a motor has a rotational speed less than a predetermined rotational speed and that a synchronous PWM control is performed if the motor has a rotational speed greater than or equal to the predetermined rotational speed, when a low-PWM frequency command signal is input.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 26, 2012
    Applicant: NABTESCO CORPORATION
    Inventors: Tokuji TSUNEMATSU, Kazushige NAKAJIMA, Hiroyuki KITAZWA, Tomoyuki YOKOGAWA