Patents by Inventor Yasuhiko Wada
Yasuhiko Wada 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).
-
Publication number: 20230324258Abstract: A failure diagnosis apparatus includes a controller to control drive of a motor, a wear estimator to estimate an amount of wear of a bearing of the motor based on a current that flows in the motor, and a failure notification unit to diagnose a failure of the motor based on the amount of wear of the bearing of the motor estimated by the wear estimator and to notify a user. When the wear estimator estimates the amount of wear of the bearing of the motor, the controller controls drive of the motor such that the motor is driven in a constant state.Type: ApplicationFiled: October 13, 2020Publication date: October 12, 2023Inventors: Yasuhiko WADA, Kazunori SAKANOBE
-
Publication number: 20230251014Abstract: A refrigerating and air-conditioning apparatus that performs defrosting operation, the refrigerating and air-conditioning apparatus including: a refrigerant circuit in which a compressor, a first heat exchanger, an expansion device, a second heat exchanger, and a four-way valve are connected to each other by pipes to allow refrigerant to circulate through the refrigerant circuit; a temperature sensor configured to measure a temperature of the compressor; and a heat generation control unit configured to increase a temperature of the compressor when the heat generation control unit detects a decrease in a value measured by the temperature sensor in defrosting operation performed on the first heat exchanger.Type: ApplicationFiled: August 21, 2020Publication date: August 10, 2023Inventors: Kazunori SAKANOBE, Kenta YUASA, Yasuhiko WADA, Chitose TANAKA
-
Patent number: 11682989Abstract: A motor control device includes: a power converter to which a first motor and a second motor are connected in parallel, the power converter being configured to convert a direct-current voltage into an alternating-current voltage and supply the alternating-current voltage to the first motor and the second motor; a switching unit provided between the second motor and the power converter; a current detector configured to detect an electric current flowing through the first motor and the second motor; and a controller configured to control the power converter based on at least a current value detected by the current detector. The controller deactivates the power converter upon receiving from outside an abnormal step signal, attributed to the occurrence of an abnormality, that excludes a normal stop signal representing a stop command and switches the switching unit from an on state to an off state upon deactivation of the power converter.Type: GrantFiled: March 7, 2019Date of Patent: June 20, 2023Assignee: Mitsubishi Electric CorporationInventors: Junki Ishizaki, Yasuhiko Wada, Akihiro Tsumura
-
Patent number: 11658601Abstract: A motor control device includes a power converter that supplies a three-phase voltage to two motors being connected in parallel, a three-phase power line that connects between one of the two motors and the power converter, a branch three-phase power line that connects between the other of the two motors and the power converter, a switching device having two switches that are provided on the branch three-phase power line, a current detection device that detects three-phase currents flowing in the two motors, and a controller. The controller performs a failure determination of the switching device by identifying a phase of a power line in which no current flows in the three-phase power line and the branch three-phase power line, and, when a failure is detected in one of the two switches in the failure determination, controls to change a state of the other switch, which operates normally, to coincide with a state of the failed switch.Type: GrantFiled: April 23, 2019Date of Patent: May 23, 2023Assignee: Mitsubishi Electric CorporationInventors: Toshiki Asai, Akihiro Tsumura, Yasuhiko Wada, Junji Morimoto, Shigeo Takata
-
Publication number: 20220374738Abstract: A failure prediction device that predicts a failure of a bearing of a compressor mounted on an air-conditioner, the failure prediction device including an observation unit that acquires, as state variables, a first state variable indicating a state of a motor and a second state variable indicating a state of an electrical device, a conversion unit that converts the state variables into a frequency domain, a generation unit that generates failure information on a failure of the bearing using frequency characteristics of the state variables obtained by converting the state variables into the frequency domain by the conversion unit and a learned model representing a relationship between the frequency characteristics of the state variables and model failure information on the failure of the bearing, and an output unit based on the failure information generated by the generation unit.Type: ApplicationFiled: November 12, 2019Publication date: November 24, 2022Inventors: Yasuhiko WADA, Kazunori SAKANOBE, Kenta YUASA
-
Publication number: 20220345070Abstract: A motor control device includes a power converter that supplies a three-phase voltage to two motors being connected in parallel, a three-phase power line that connects between one of the two motors and the power converter, a branch three-phase power line that connects between the other of the two motors and the power converter, a switching device having two switches that are provided on the branch three-phase power line, a current detection device that detects three-phase currents flowing in the two motors, and a controller. The controller performs a failure determination of the switching device by identifying a phase of a power line in which no current flows in the three-phase power line and the branch three-phase power line, and, when a failure is detected in one of the two switches in the failure determination, controls to change a state of the other switch, which operates normally, to coincide with a state of the failed switch.Type: ApplicationFiled: April 23, 2019Publication date: October 27, 2022Inventors: Toshiki ASAI, Akihiro TSUMURA, Yasuhiko WADA, Junji MORIMOTO, Shigeo TAKATA
-
Patent number: 11456684Abstract: An electric motor control device that drives and controls a plurality of electric motors connected in parallel, includes: a power conversion device; a current detection device; and a controller that includes a first control unit to perform first control on each of the plurality of electric motors based on the electric current, a second control unit to perform second control of controlling the plurality of electric motors such that an estimated speed of each of the plurality of electric motors obtained based on the current value follows the speed command value, and a switching determination unit to perform switching determination processing of switching between the first control performed by the first control unit and the second control performed by the second control unit according to drive information on at least one or more of the plurality of electric motors.Type: GrantFiled: November 2, 2018Date of Patent: September 27, 2022Assignee: Mitsubishi Electric CorporationInventors: Yasuhiko Wada, Akihiro Tsumura
-
Patent number: 11424698Abstract: A motor control device includes: an inverter circuit configured to convert a direct-current voltage into an alternating-current voltage, and to supply the alternating-current voltage to a plurality of motors connected in parallel; current detectors configured to detect motor currents flowing through the respective motors; a relay provided between at least one of the plurality of motors and the inverter circuit; and a controller configured to change the number of motors to be driven. When one of two or more motors under driving is stopped, the controller lowers a current instruction value to the two or more motors under driving. When a monitor current that is the motor current detected by the current detector of the motor connected to the relay is decreased, the controller switches the relay from an on state to an off state.Type: GrantFiled: January 16, 2019Date of Patent: August 23, 2022Assignee: Mitsubishi Electric CorporationInventors: Akihiro Tsumura, Yuichi Shimizu, Yasuhiko Wada, Junji Morimoto
-
Publication number: 20220103096Abstract: A load driving apparatus includes first and second motors that drive a plurality of loads on a one-to-one basis, and an inverter that applies a common voltage to the first and second motors. The first motor is vector-controlled by a control unit. The second motor is driven by the common voltage. The ratio of the winding resistance value of the second motor to the winding resistance value of the first motor as a reference motor is 2.4 or more.Type: ApplicationFiled: May 13, 2019Publication date: March 31, 2022Inventors: Yuichi SHIMIZU, Yuki TANIYAMA, Yasuhiko WADA
-
Publication number: 20220094284Abstract: A motor control device includes: a power converter to which a first motor and a second motor are connected in parallel, the power converter being configured to convert a direct-current voltage into an alternating-current voltage and supply the alternating-current voltage to the first motor and the second motor; a switching unit provided between the second motor and the power converter; a current detector configured to detect an electric current flowing through the first motor and the second motor; and a controller configured to control the power converter based on at least a current value detected by the current detector. The controller deactivates the power converter upon receiving from outside an abnormal step signal, attributed to the occurrence of an abnormality, that excludes a normal stop signal representing a stop command and switches the switching unit from an on state to an off state upon deactivation of the power converter.Type: ApplicationFiled: March 7, 2019Publication date: March 24, 2022Inventors: Junki ISHIZAKI, Yasuhiko WADA, Akihiro TSUMURA
-
Publication number: 20220021318Abstract: A motor control device includes: an inverter circuit configured to convert a direct-current voltage into an alternating-current voltage, and to supply the alternating-current voltage to a plurality of motors connected in parallel; current detectors configured to detect motor currents flowing through the respective motors; a relay provided between at least one of the plurality of motors and the inverter circuit; and a controller configured to change the number of motors to be driven. When one of two or more motors under driving is stopped, the controller lowers a current instruction value to the two or more motors under driving. When a monitor current that is the motor current detected by the current detector of the motor connected to the relay is decreased, the controller switches the relay from an on state to an off state.Type: ApplicationFiled: January 16, 2019Publication date: January 20, 2022Inventors: Akihiro TSUMURA, Yuichi SHIMIZU, Yasuhiko WADA, Junji MORIMOTO
-
Patent number: 11196361Abstract: An electric motor control device controls driving of electric motors connected in parallel with each other and includes a power converter converting power from a power supply, and supply the converted power to each of the electric motors, a switching device to be turned on to electrically connect the power converter and at least one of the electric motors and to be turned off to electrically disconnect the power converter and the at least one of the electric motors, a current detection unit detecting a current that flows in the electric motors, and a controller controlling the power converter on the basis of operation of the switching device, rotation frequency command values from an external device, and a value of the current detected by the current detection unit. The controller turns the switching device from off to on so that start timing of control is different for each electric motor.Type: GrantFiled: October 3, 2017Date of Patent: December 7, 2021Assignee: Mitsubishi Electric CorporationInventors: Yasuhiko Wada, Akihiro Tsumura
-
Patent number: 11133762Abstract: A drive system includes a current detection unit that detects a current flowing to a main synchronous motor, and a current detection unit that detects a current flowing to a secondary synchronous motor. The drive system includes a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the main synchronous motor, and a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the secondary synchronous motor. The drive system includes a current control unit that outputs a voltage command, and a secondary torque current pulsating component extraction unit that extracts a pulsating component. The drive system includes a subtracter that determines an angle difference, and a magnetic flux current command determination unit that determines a magnetic flux current command.Type: GrantFiled: January 18, 2018Date of Patent: September 28, 2021Assignee: Mitsubishi Electric CorporationInventors: Kenji Takahashi, Tsukasa Masumura, Akihiro Tsumura, Yasuhiko Wada, Akane Hongyo
-
Publication number: 20210184604Abstract: An electric motor control device that drives and controls a plurality of electric motors connected in parallel, includes: a power conversion device; a current detection device; and a controller that includes a first control unit to perform first control on each of the plurality of electric motors based on the electric current, a second control unit to perform second control of controlling the plurality of electric motors such that an estimated speed of each of the plurality of electric motors obtained based on the current value follows the speed command value, and a switching determination unit to perform switching determination processing of switching between the first control performed by the first control unit and the second control performed by the second control unit according to drive information on at least one or more of the plurality of electric motors.Type: ApplicationFiled: November 2, 2018Publication date: June 17, 2021Inventors: Yasuhiko WADA, Akihiro TSUMURA
-
Patent number: 11012011Abstract: A motor control device includes an inverter configured by a plurality of arms, a smoothing unit supplying a direct-current voltage to the inverter, a shunt resistor inserted between a lower-arm switching element for each phase of the inverter and a negative-electrode side of the smoothing unit, a master motor current sensor outputting a voltage according to a current flowing in a first motor connected in parallel to the inverter, and a computing unit generating driving signals for a plurality of switching elements based on an output of the master motor current sensor and an output corresponding to a voltage drop on the shunt resistor.Type: GrantFiled: April 27, 2017Date of Patent: May 18, 2021Assignee: Mitsubishi Electric CorporationInventors: Keisuke Uemura, Kenji Takahashi, Yasuhiko Wada, Akihiro Tsumura
-
Patent number: 10951140Abstract: A synchronous motor drive device drives a plurality of synchronous motors, and includes a power converter that converts power to supply power to the plurality of synchronous motors, a first switch device that electrically connects or disconnects between the power converter and each of the plurality of synchronous motors, and a controller that, based on a higher order command, performs stability judgment processing of the plurality of synchronous motors, determines the number of synchronous motors to be driven and a drive speed from among the plurality of synchronous motors, selects a synchronous motor corresponding to the number of the synchronous motors from among the plurality of synchronous motors, controls the first switch device corresponding to the selected synchronous motor to electrically connect the power converter to the synchronous motor and to supply the power, and instructs, to the power converter, the drive speed of the synchronous motor to be driven.Type: GrantFiled: April 5, 2017Date of Patent: March 16, 2021Assignee: Mitsubishi Electric CorporationInventors: Tsukasa Masumura, Kenji Takahashi, Yasuhiko Wada
-
Publication number: 20210067066Abstract: A drive system includes a current detection unit that detects a current flowing to a main synchronous motor, and a current detection unit that detects a current flowing to a secondary synchronous motor. The drive system includes a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the main synchronous motor, and a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the secondary synchronous motor. The drive system includes a current control unit that outputs a voltage command, and a secondary torque current pulsating component extraction unit that extracts a pulsating component. The drive system includes a subtracter that determines an angle difference, and a magnetic flux current command determination unit that determines a magnetic flux current command.Type: ApplicationFiled: January 18, 2018Publication date: March 4, 2021Inventors: Kenji TAKAHASHI, Tsukasa MASUMURA, Akihiro TSUMURA, Yasuhiko WADA, Akane HONGYO
-
Publication number: 20210006185Abstract: An electric motor control device controls driving of electric motors connected in parallel with each other and includes a power converter converting power from a power supply, and supply the converted power to each of the electric motors, a switching device to be turned on to electrically connect the power converter and at least one of the electric motors and to be turned off to electrically disconnect the power converter and the at least one of the electric motors, a current detection unit detecting a current that flows in the electric motors, and a controller controlling the power converter on the basis of operation of the switching device, rotation frequency command values from an external device, and a value of the current detected by the current detection unit. The controller turns the switching device from off to on so that start timing of control is different for each electric motor.Type: ApplicationFiled: October 3, 2017Publication date: January 7, 2021Inventors: Yasuhiko WADA, Akihiro TSUMURA
-
Publication number: 20200244194Abstract: A synchronous motor drive device drives a plurality of synchronous motors, and includes a power converter that converts power to supply power to the plurality of synchronous motors, a first switch device that electrically connects or disconnects between the power converter and each of the plurality of synchronous motors, and a controller that, based on a higher order command, performs stability judgment processing of the plurality of synchronous motors, determines the number of synchronous motors to be driven and a drive speed from among the plurality of synchronous motors, selects a synchronous motor corresponding to the number of the synchronous motors from among the plurality of synchronous motors, controls the first switch device corresponding to the selected synchronous motor to electrically connect the power converter to the synchronous motor and to supply the power, and instructs, to the power converter, the drive speed of the synchronous motor to be driven.Type: ApplicationFiled: April 5, 2017Publication date: July 30, 2020Inventors: Tsukasa MASUMURA, Kenji TAKAHASHI, Yasuhiko WADA
-
Patent number: 10581365Abstract: A power converting apparatus for applying to a load an alternating-current voltage converted from a direct-current voltage includes an inverter that receives a PWM signal and applies the alternating-current voltage to the load and an inverter control unit that generates the PWM signal and supplies the PWM signal to the inverter. The frequency of the PWM signal is an integer multiple of the frequency of the alternating-current voltage. The alternating-current voltage includes a plurality of positive pulses and a plurality of negative pulses in one cycle of the alternating-current voltage. The number of the positive pulses and the number of the negative pulses are equal.Type: GrantFiled: September 4, 2015Date of Patent: March 3, 2020Assignee: Mitsubishi Electric CorporationInventors: Kazunori Hatakeyama, Keisuke Uemura, Takahiko Kobayashi, Yasuhiko Wada