Patents Assigned to Kyosan Electric Mfg. Co., Ltd.
  • Patent number: 11929668
    Abstract: In the present invention, when a DC reactor is in a magnetically saturated state, the on/off operations of a switching element are suspended and the switching element is set to an off state for a predetermined period of time, thereby resetting the magnetic saturation of the DC reactor and maintaining the supply of power to a load. After resetting the magnetic saturation, the pulse output of the normal pulse mode is restarted.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: March 12, 2024
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki
  • Publication number: 20240048041
    Abstract: A carrier wave generation unit comprising a wideband RF power supply divides a whole modulation wave variable frequency range into a plurality of modulation wave frequency sections associated with the number of PWM pulses N based on upper and lower limit frequencies of a carrier wave. In each modulation wave frequency section, an integer number of PWM pulses N associated to each modulation wave frequency section and the modulation wave frequency fs are used to vary a carrier wave frequency fc based on the relationship of fc=N·fs, thereby synchronizing the frequency between a carrier wave C and a modulation wave S to satisfy periodicity.
    Type: Application
    Filed: December 17, 2021
    Publication date: February 8, 2024
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Tomohiro Yoneyama, Shohei Kobayashi, Yu Hosoyamada
  • Patent number: 11884313
    Abstract: A railroad equipment state determination apparatus includes: a storage that stores a plurality of operation data associated with a prescribed operation performed by railroad equipment that is driven by a motor from a stopped state to perform the prescribed operation and then comes into the stopped state again; an evaluation criteria setting section that sets evaluation criteria based on the plurality of operation data stored in the storage; and a determination section that determines whether new operation data resulting from the prescribed operation newly performed by the railroad equipment is abnormal based on the evaluation criteria.
    Type: Grant
    Filed: August 18, 2020
    Date of Patent: January 30, 2024
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Toshio Kitajima, Youichi Murakami
  • Patent number: 11881777
    Abstract: This DC-pulse power supply device is provided with: a DC power supply; a pulse unit (20) for generating a pulse output using a step-up chopper circuit connected to the DC power supply; and a voltage superimposing unit (30A, 30B) connected to a DC reactor of the step-up chopper circuit. The voltage superimposing unit (30A, 30B) superimposes an amount (Vc, VDCL2) corresponding to a superimposed voltage on the output voltage of the step-up chopper circuit. The pulse unit (20) outputs, in a pulse form, the output voltage (Vo) on which the amount (Vc, VDCL2) corresponding to the superimposed voltage is superimposed by the voltage superimposing unit (30A, 30B). The amount corresponding to the superimposed voltage is superimposed on the pulse output of the step-up chopper circuit, thereby raising the output voltage of the pulse output of the step-up chopper circuit.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: January 23, 2024
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki
  • Publication number: 20230421152
    Abstract: A switching module comprising: a GaN-FET mounted on a substrate; a driver circuit connected to a gate electrode of the GaN-FET via a gate resistor; and a driver power supply for supplying a drive voltage to the driver circuit. The driver circuit is configured such that a plurality of logic integrated circuits are connected in parallel.
    Type: Application
    Filed: June 22, 2021
    Publication date: December 28, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Hiroshi Kunitama, Takuya Yoshida
  • Patent number: 11852665
    Abstract: A pulsed high frequency monitor of the present invention monitors the power level of a pulsed high frequency on the basis of a transition pattern in which the power level changes in time series instead of monitoring the power level by comparing the power level of the pulsed high frequency with a threshold value. The pulsed high frequency monitor comprises: a DC circuit that converts the pulsed high frequency into DC and outputs the power level; a power level change detection circuit that detects a level change of the power level; and a transition pattern determination circuit that determines a time-series transition pattern of the power level on the basis of the level change detected by the power level change detection circuit.
    Type: Grant
    Filed: August 5, 2020
    Date of Patent: December 26, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Hiroyuki Kojima, Ryota Suzuki
  • Patent number: 11799373
    Abstract: This DC pulse power supply device includes: a DC power supply unit (10); and a pulsing unit (20) that generates a pulse output using a step-up chopper circuit connected to the DC power supply unit. A clamp voltage unit (30) has an output end that is connected to a connection point (s) between a switching element (22) and a DC reactor (21), and applies a clamp voltage (VC) to one end of the switching element (22). During an off period (Toff) of the step-up chopper circuit, the voltage at both ends of the switching element is clamped so as to prevent damage to the switching element, suppress output voltage fluctuations resulting from load current fluctuations, and suppress power loss caused by a load current and a discharge current flowing through a resistor.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: October 24, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki
  • Patent number: 11764666
    Abstract: This DC pulse power supply device comprises a voltage clamper including a capacitor that is connected in parallel to a DC reactor in a chopper circuit provided in a pulsing unit in order to suppress increases in the surge voltage resulting from the leakage inductance of the DC reactor. During the start-up of pulsing operation, which is the initial stage of the pulse mode, the frequency of the pulsing operation of the chopper circuit is controlled over the period until the capacitor voltage is charged to a sufficient voltage to reset the magnetic saturation of the DC reactor.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: September 19, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki
  • Patent number: 11728734
    Abstract: The present invention suppresses influence of control due to the delay time in voltage switching between a plurality of different voltages. A DC/DC converter comprises: a main circuit including a switching circuit; a control unit that performs discrete control by discrete control toward a command value; and a switching signal generation unit that generates a switching signal that drives the switching circuit. The control unit calculates the pulse width ?T(k) of the switching signal having the delay time Td as a parameter as an operation amount of discrete control performed every control period Ts. The switching signal generation unit generates a switching signal based on the pulse width ?T(k) obtained by the calculation in the control unit. The main circuit switches the voltage level by driving the switching circuit based on the switching signal of the switching signal generation unit.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: August 15, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Yu Hosoyamada
  • Patent number: 11677385
    Abstract: In a DC pulse power supply device according to the present invention, at the time of starting pulsing operation, the duty of the pulsing operation of a chopper circuit is controlled, a switching element is set to an ON state, and the pulse width at which the DC reactor is in an energized state is made variable over the period until the capacitor voltage is charged to a sufficient voltage to reset the magnetic saturation of the DC reactor. Gradually increasing the pulse width suppresses the degree of increase in the DC reactor current, and suppresses the DC reactor current below the magnetic saturazion level. As a result, the magnetic saturation of the DC reactor is suppressed at the time of starting pulsing operation.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: June 13, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki
  • Publication number: 20230134559
    Abstract: Provided are a high-frequency power supply device and an output control method therefor which are capable of constantly keeping the phase of the outputted high-frequency pulse uniform even in a structure in which the synchronizing pulse and the clock pulse are generated separately.
    Type: Application
    Filed: March 4, 2021
    Publication date: May 4, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Takeshi Fujiwara, Hiroyuki Kojima, Satoshi Kawai
  • Publication number: 20230134084
    Abstract: A high-frequency power supply device is provided with an AC-DC converter for converting an input from a three-phase alternating-current source into a direct current and a high-frequency amplifier including multiple FET elements and outputting a high-frequency alternating-current power, with the output of the AC-DC converter being directly input to the high-frequency amplifier, and further includes a phase conversion circuit for imparting phase differences to gate signals to be input to the multiple FET elements so as to offset fluctuation components included in the direct current. The device generates the high-frequency alternating-current power by converting the input from the three-phase alternating-current source into the direct current, directly inputting the direct current to the high-frequency amplifier, imparting the phase differences to the gate signals to be input to the multiple FET elements so as to offset the fluctuation components included in the direct current, and performing switching.
    Type: Application
    Filed: December 24, 2020
    Publication date: May 4, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Hiroshi Kunitama, Kunihiro Muto, Takuya Yoshida, Koichi Miyazaki
  • Publication number: 20230124064
    Abstract: A high-frequency power supply device, which outputs high-frequency pulses to a target device on the basis of a synchronous pulse and a clock pulse, and the output control method therefor are such that a period reference signal is generated from output timing information pertaining to the synchronous pulse, an output level signal is generated from output level information, an output stop time is timed on the basis of the period reference signal and an output stop signal is generated, and, when the period reference signal, the output level signal, and the clock pulse are received and a high-frequency pulse is formed on the basis of these signals, transmission of the output level signal is stopped while the output stop signal is being received.
    Type: Application
    Filed: March 4, 2021
    Publication date: April 20, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Takeshi Fujiwara, Yuya Yasuda, Ryuhei Katafuchi, Hiroyuki Kojima
  • Publication number: 20230112281
    Abstract: The present invention suppresses unevenness of an input/output current of a full bridge circuit, which is caused due to a cross current generated by a delay operation or the like of a switching element and unevenness of a driver voltage of each switching element, and suppresses an occurrence of an erroneous operation of an amplifier of a class-D full bridge circuit. A driver device of a class-D full bridge amplifier according to the present invention sets, at the same potential in terms of DC, reference potentials on a low-voltage side of two high-side driver circuits which drive two high-side switching elements which constitute a full bridge circuit, and suppresses an occurrence of unevenness of a driver voltage of the switching elements due to a cross current which flows between the bridge circuit and the high-side driver circuits.
    Type: Application
    Filed: March 17, 2021
    Publication date: April 13, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Satoshi Aikawa, Tadaharu Ohno
  • Patent number: 11616454
    Abstract: In this power conversion device, a phase deviation of an output voltage due to a phase shift control is eliminated. The power conversion device according to the present invention converts DC voltage to AC voltage by phase-shift controlling the switching elements of a full bridge inverter. In place of a conventional method in which only one of the first and second legs of the full bridge inverter is phase-shifted, both legs are phase-shifted in opposite directions to each other to control an overlap angle at which the switching elements of the first and second legs of the full bridge are simultaneously brought into an on-state. The variation of the center phase of the overlap angle is suppressed by phase-shifting the first and second legs in the opposite directions to each other.
    Type: Grant
    Filed: March 18, 2020
    Date of Patent: March 28, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventor: Kunihiro Muto
  • Publication number: 20230073768
    Abstract: The present invention controls, within a frequency range, an output command value not to exceed the upper limit of an output command permitted by a high-frequency amplifier. A method for controlling a high-frequency power supply device and the high-frequency power supply device involve performing frequency control within a frequency range of variable frequencies, limiting the upper limit of an output command value for controlling an output of a high-frequency amplifier within the frequency range of variable frequencies on the basis of an output limit value, and thereby preventing damaging of the high-frequency amplifier caused by an excessive command.
    Type: Application
    Filed: February 12, 2021
    Publication date: March 9, 2023
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Atsushi Takayanagi, Toshinori Takeuchi, Hirokazu Takada, Soichi Yokoyama, Hiro Nakayama
  • Patent number: 11548486
    Abstract: Upon detecting a current balise, an onboard system of a train calculates a speed curve based on measured traveling speed at a timing of the detection and sets a minimum required time period for traveling to each of a next balise and a balise subsequent to the next balise. Upon detecting the next balise, the onboard system compares a traveling time period from the timing of detecting the current balise to the timing of detecting the next balise with the set minimum required time period. The onboard system activates an emergency brake when the elapsed time period is shorter than the minimum required time period to stop the train.
    Type: Grant
    Filed: March 26, 2019
    Date of Patent: January 10, 2023
    Assignee: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Kenji Mizuno, Shuji Nambu, Toshifumi Nishi, Tamotsu Yokoyama
  • Publication number: 20220345053
    Abstract: In this power conversion device, a phase deviation of an output voltage due to a phase shift control is eliminated. The power conversion device according to the present invention converts DC voltage to AC voltage by phase-shift controlling the switching elements of a full bridge inverter. In place of a conventional method in which only one of the first and second legs of the full bridge inverter is phase-shifted, both legs are phase-shifted in opposite directions to each other to control an overlap angle at which the switching elements of the first and second legs of the full bridge are simultaneously brought into an on-state. The variation of the center phase of the overlap angle is suppressed by phase-shifting the first and second legs in the opposite directions to each other.
    Type: Application
    Filed: March 18, 2020
    Publication date: October 27, 2022
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventor: Kunihiro Muto
  • Publication number: 20220276289
    Abstract: A pulsed high frequency monitor of the present invention monitors the power level of a pulsed high frequency on the basis of a transition pattern in which the power level changes in time series instead of monitoring the power level by comparing the power level of the pulsed high frequency with a threshold value. The pulsed high frequency monitor comprises: a DC circuit that converts the pulsed high frequency into DC and outputs the power level; a power level change detection circuit that detects a level change of the power level; and a transition pattern determination circuit that determines a time-series transition pattern of the power level on the basis of the level change detected by the power level change detection circuit.
    Type: Application
    Filed: August 5, 2020
    Publication date: September 1, 2022
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Hiroyuki Kojima, Ryota Suzuki
  • Publication number: 20220209651
    Abstract: This DC pulse power supply device comprises a voltage clamper including a capacitor that is connected in parallel to a DC reactor in a chopper circuit provided in a pulsing unit in order to suppress increases in the surge voltage resulting from the leakage inductance of the DC reactor. During the start-up of pulsing operation, which is the initial stage of the pulse mode, the frequency of the pulsing operation of the chopper circuit is controlled over the period until the capacitor voltage is charged to a sufficient voltage to reset the magnetic saturation of the DC reactor.
    Type: Application
    Filed: November 8, 2019
    Publication date: June 30, 2022
    Applicant: KYOSAN ELECTRIC MFG. CO., LTD.
    Inventors: Itsuo Yuzurihara, Toshiyuki Adachi, Tomohiro Yoneyama, Koichi Miyazaki