Patents by Inventor Masayoshi Suhama

Masayoshi Suhama 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).

  • Patent number: 9641106
    Abstract: An electric vehicle driven by a synchronous motor 21 and an induction motor 31, and braked with a first regenerative torque BT1 generated by the synchronous motor generator 21 and a second regenerative torque BT2 generated by the induction motor generator 31. The ratio of the first regenerative torque BT1 to the second regenerative torque BT2 is changed in accordance with a state of charge (SOC) of a battery 11. In this way, a switching frequency from a regenerative brake to a hydraulic brake is restricted to improve drivability when a state of charge (SOC) of the battery 11 is high.
    Type: Grant
    Filed: January 8, 2015
    Date of Patent: May 2, 2017
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Takashi Ota, Ryoji Sato, Masayoshi Suhama
  • Patent number: 9515583
    Abstract: A rotary electric machine control system includes a rotary electric machine (second motor generator), a number-of-revolutions sensor that measures the number of revolutions per predetermined time period of the rotary electric machine, and a controller. The controller has a threshold changing unit for changing a control switching phase that is a control switching threshold to be used for switching the control mode of the rotary electric machine, according to a measurement result of the number of revolutions.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: December 6, 2016
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, AISIN AW CO., LTD.
    Inventors: Masayoshi Suhama, Kazuhide Miyata, Daisuke Ogino
  • Patent number: 9272704
    Abstract: A hybrid vehicle provided with a battery 10, a boost converter 20, a first inverter 30, a second inverter 40, a first motor generator (MG) 50 connected to the first inverter 30, a second MG 60 connected to the second inverter 40, an engine 70 capable of driving the first MG 50, and a controller 90 which starts and stops the boost converter 20. When electric power transmitted between the battery 10 and the boost converter 20 is equal to or below a predetermined threshold, the boost converter 20 is stopped. When an actual boost voltage of the boost converter 20 reaches a predetermined threshold, the first MG 50 is driven by the engine 70. In this way, the system efficiency of a hybrid vehicle can be advantageously improved by efficiently maintaining the boost converter at a halt for a sufficiently long period.
    Type: Grant
    Filed: January 8, 2015
    Date of Patent: March 1, 2016
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Ryoji Sato, Masayoshi Suhama
  • Publication number: 20150210267
    Abstract: A hybrid vehicle provided with a battery 10, a boost converter 20, a first inverter 30, a second inverter 40, a first motor generator (MG) 50 connected to the first inverter 30, a second MG 60 connected to the second inverter 40, an engine 70 capable of driving the first MG 50, and a controller 90 which starts and stops the boost converter 20. When electric power transmitted between the battery 10 and the boost converter 20 is equal to or below a predetermined threshold, the boost converter 20 is stopped. When an actual boost voltage of the boost converter 20 reaches a predetermined threshold, the first MG 50 is driven by the engine 70. In this way, the system efficiency of a hybrid vehicle can be advantageously improved by efficiently maintaining the boost converter at a halt for a sufficiently long period.
    Type: Application
    Filed: January 8, 2015
    Publication date: July 30, 2015
    Inventors: Ryoji Sato, Masayoshi Suhama
  • Publication number: 20150200613
    Abstract: An electric vehicle driven by a synchronous motor 21 and an induction motor 31, and braked with a first regenerative torque BT1 generated by the synchronous motor generator 21 and a second regenerative torque BT2 generated by the induction motor generator 31. The ratio of the first regenerative torque BT1 to the second regenerative torque BT2 is changed in accordance with a state of charge (SOC) of a battery 11. In this way, a switching frequency from a regenerative brake to a hydraulic brake is restricted to improve drivability when a state of charge (SOC) of the battery 11 is high.
    Type: Application
    Filed: January 8, 2015
    Publication date: July 16, 2015
    Inventors: Takashi Ota, Ryoji Sato, Masayoshi Suhama
  • Publication number: 20140340007
    Abstract: A rotary electric machine control system includes a rotary electric machine (second motor generator), a number-of-revolutions sensor that measures the number of revolutions per predetermined time period of the rotary electric machine, and a controller. The controller has a threshold changing unit for changing a control switching phase that is a control switching threshold to be used for switching the control mode of the rotary electric machine, according to a measurement result of the number of revolutions.
    Type: Application
    Filed: September 11, 2012
    Publication date: November 20, 2014
    Applicants: AISIN AW CO., LTD., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayoshi Suhama, Kazuhide Miyata, Daisuke Ogino
  • Patent number: 8866435
    Abstract: A control device controls an inverter controlling an output of a motor by PWM control. The control device calculates a reference frequency based on a torque and a rotation speed of the motor, calculates a random coefficient using two data tables, and calculates, as a random frequency, a value obtained by adding, to a reference frequency, a value obtained by multiplying a prescribed width by the random coefficient. The control device calculates control limit lines based on the rotation speed of the motor, and corrects the random frequency so as to fall within a range that is higher than the control limit line and lower than the control limit line. The control device generates a carrier signal having a random frequency as a carrier frequency.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: October 21, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayoshi Suhama, Kenji Yamada, Tetsuhiro Itoh, Satoru Katoh
  • Patent number: 8682520
    Abstract: A controller for a vehicle including two inverters determines whether a detector currently performs an insulation determination process, and if not, the controller performs random control to randomly vary carrier frequencies corresponding to the two inverters, respectively. In contrast, if the insulation determination process is currently performed, the controller prohibits the random control and fixes the carrier frequencies at reference frequencies, respectively. The reference frequencies are previously set to have a difference ?fs larger than a predetermined value f1.
    Type: Grant
    Filed: July 14, 2010
    Date of Patent: March 25, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kenji Yamada, Masayoshi Suhama
  • Patent number: 8581533
    Abstract: A controller controls switching of IGBT devices of an inverter according to the desired output of the permanent magnet motor. The controller includes: a magnet temperature detection device that detects the magnet temperature of the permanent magnet motor based on the output of a temperature sensor; a setting device that sets a threshold value of the magnet temperature corresponding to the desired output of the permanent magnet motor, based on a predetermined relation between the output from the permanent magnet motor and a critical temperature, up to which demagnetization in the permanent magnet motor is not caused; and a carrier frequency control device that, when the magnet temperature detected by the magnet temperature detection device exceeds the threshold value, changes the carrier frequency, at which the IGBT devices are switched, such that a ripple current superimposed on a motor current that flows through the permanent magnet motor is reduced.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: November 12, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kazuhito Hayashi, Masayoshi Suhama
  • Patent number: 8502493
    Abstract: When instructed to switch control modes between overmodulation PWM control and sinusoidal wave PWM control, control device corrects the amplitude of a voltage command signal based on a state of power conversion operation performed by an inverter, so as to suppress a change in an influence of dead time over a voltage applied to an alternating-current motor upon switching the control modes. The state of the power conversion operation performed by the inverter includes at least one of a present value of a carrier frequency in a control mode currently employed, an estimated value of the carrier frequency to be obtained when switching the control modes, the length of the dead time, a power factor of alternating-current power exchanged between the inverter and the alternating-current motor, and a driving state of the alternating-current motor.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: August 6, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayoshi Suhama, Shogo Tanaka
  • Patent number: 8482234
    Abstract: A motor drive control device includes a battery, a converter, an inverter, and a control section for outputting control signals to the converter and the inverter. The control section has a first map and a second map regarding control of the alternating-current motor and further includes a map switching section for switching from control based on the first map to control based on the second map in accordance with conditions of the battery.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: July 9, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshifumi Yamakawa, Hideto Hanada, Kazuhito Hayashi, Masayoshi Suhama
  • Publication number: 20130169206
    Abstract: A control device controls an inverter controlling an output of a motor by PWM control. The control device calculates a reference frequency based on a torque and a rotation speed of the motor, calculates a random coefficient using two data tables, and calculates, as a random frequency, a value obtained by adding, to a reference frequency, a value obtained by multiplying a prescribed width by the random coefficient. The control device calculates control limit lines based on the rotation speed of the motor, and corrects the random frequency so as to fall within a range that is higher than the control limit line and lower than the control limit line. The control device generates a carrier signal having a random frequency as a carrier frequency.
    Type: Application
    Filed: June 7, 2010
    Publication date: July 4, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayoshi Suhama, Kenji Yamada, Tetsuhiro Itoh, Satoru Katoh
  • Publication number: 20130144477
    Abstract: A controller for a vehicle including two inverters determines whether a detector currently performs an insulation determination process, and if not, the controller performs random control to randomly vary carrier frequencies corresponding to the two inverters, respectively. In contrast, if the insulation determination process is currently performed, the controller prohibits the random control and fixes the carrier frequencies at reference frequencies, respectively. The reference frequencies are previously set to have a difference ?fs larger than a predetermined value f1.
    Type: Application
    Filed: July 14, 2010
    Publication date: June 6, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kenji Yamada, Masayoshi Suhama
  • Patent number: 8395277
    Abstract: A vehicle includes a converter for stepping up power provided from a power storage device, and an inverter for converting the power output from converter and outputting it to an alternating-current motor for driving the vehicle. In the vehicle, a rectangular voltage control unit controls the inverter by means of rectangular wave voltage control that is based on a torque command value and the like, so as to control an output torque of the alternating-current motor. A system voltage control unit controls a system voltage, which is an output voltage of the converter. The system voltage control unit lifts a restriction on a system voltage command value based on an accelerator pedal position and the like, and then increases it. When increasing the system voltage command value during the rectangular wave voltage control for the inverter, a cooperative control unit increases the system voltage command value and the torque command value in a cooperative manner.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: March 12, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshifumi Yamakawa, Hideto Hanada, Kazuhito Hayashi, Masayoshi Suhama, Toshiya Hashimoto
  • Patent number: 8324856
    Abstract: In the hybrid vehicle, a boost converter is controlled to make a post-boost voltage or a voltage on the side of an inverter become a target post-boost voltage corresponding to a target operation point of a motor in accordance with a target post-boost voltage setting map that divides an operation region of the motor into a non-boost region and a boost region when a operation point of the motor is included in the boost region. The target post-boost voltage setting map is prepared so that the non-boost region includes a region in which a loss produced by driving the motor when not boosting the post-boost voltages becomes smaller than the loss produced when boosting the post-boost voltage and the boost region includes a region in which the loss produced when boosting the post-boost voltage becomes smaller than the loss produced when not boosting the post-boost voltage.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: December 4, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshifumi Yamakawa, Hideto Hanada, Kazuhito Hayashi, Masayoshi Suhama, Masaki Okamura
  • Patent number: 8269446
    Abstract: When an electric vehicle outputs a torque instruction, firstly, a request torque is acquired and a judged whether the acquired request torque is positive or negative. Regardless of the sign of the request torque, it is judged whether the eco-switch is ON. If the request torque has a positive sign and the eco-switch is OFF, a map A is selected. If the eco-switch is ON, a map B which limits the maximum torque to a low value for the map A is selected. If the request torque has a negative sign, a map C is selected regardless of the eco-switch ON/OFF state and the maximum torque is not limited.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: September 18, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin AW Co., Ltd.
    Inventors: Masayoshi Suhama, Hideto Hanada, Masaki Okamura, Hiroaki Kioka, Ken Iwatsuki
  • Patent number: 8093843
    Abstract: By the vehicle controller of the present invention, when the economy mode is selected by a driver, boosting by a converter is limited and output torque of a motor is limited. Even in the economy mode, however, if the driver requests large torque, either the limit on boosting or the limit on output torque is cancelled. As a result, a vehicle controller for a vehicle including a battery, a converter boosting/lowering the battery voltage and a motor operating with the power from the converter is provided, by which unnecessary power consumption is reduced and the torque requested by the driver can be generated.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: January 10, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin Aw Co., Ltd.
    Inventors: Masaki Okamura, Hideto Hanada, Masayoshi Suhama, Yuki Sugiyama, Ken Iwatsuki
  • Patent number: 8089241
    Abstract: When a target operation point of either a motor MG1 or a motor MG2 is included in a resonance range specified by operation points of the motor MG1 or the motor MG2 in the occurrence of resonance in a booster converter, a hybrid vehicle controls the booster converter to make the voltage on the side of inverters approach to a preset target boosted voltage that is higher than the voltage on the side of the battery, while controlling the inverters by sine-wave control.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: January 3, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshifumi Yamakawa, Kazuhito Hayashi, Masayoshi Suhama, Hideto Hanada
  • Patent number: 8082073
    Abstract: A loss reduction module of an electric vehicle control device has a function to limit a torque to not exceed a constant loss characteristic and issue a torque instruction if a requested torque exceeds the constant loss characteristic when an ecology switch is turned ON and low fuel consumption travel is instructed. More specifically, when a requested torque exceeding the constant loss characteristic is input, a torque limit is applied to a point on the constant loss characteristic. Accordingly, the torque instruction is output as a torque which is suppressed more than a characteristic curve obtained by combining the constant loss characteristic and a characteristic indicating the relationship between the torque and the number of rotations during normal travel.
    Type: Grant
    Filed: January 23, 2008
    Date of Patent: December 20, 2011
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin AW Co., Ltd.
    Inventors: Masaki Okamura, Masayoshi Suhama, Ken Iwatsuki
  • Publication number: 20110282530
    Abstract: When an electric vehicle outputs a torque instruction, firstly, a request torque is acquired and a judged whether the acquired request torque is positive or negative. Regardless of the sign of the request torque, it is judged whether the eco-switch is ON. If the request torque has a positive sign and the eco-switch is OFF, a map A is selected. If the eco-switch is ON, a map B which limits the maximum torque to a low value for the map A is selected. If the request torque has a negative sign, a map C is selected regardless of the eco-switch ON/OFF state and the maximum torque is not limited.
    Type: Application
    Filed: June 30, 2011
    Publication date: November 17, 2011
    Applicants: AISIN AW CO., LTD., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayoshi Suhama, Hideto Hanada, Masaki Okamura, Hiroaki Kioka, Ken Iwatsuki