Patents by Inventor Shigeo Umehara
Shigeo Umehara 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: 20190229670Abstract: An electric-motor driving apparatus according to the present invention is the electric-motor driving apparatus that drives an electric motor having a winding structure in which a first multi-phase winding and a second multi-phase winding are wound and includes a first DC/AC converter connected to the first multi-phase winding and applying a multi-phase alternating-current voltage to the electric motor, a second DC/AC converter connected to the second multi-phase winding and applying a multi-phase alternating-current voltage to the electric motor, a first three-phase switching unit to perform connecting and disconnecting between phases of the first multi-phase winding, a second three-phase switching unit to perform connecting and disconnecting between phases of the second multi-phase winding, and a winding switching unit to perform connecting and disconnecting between the first multi-phase winding and the second multi-phase winding.Type: ApplicationFiled: October 13, 2016Publication date: July 25, 2019Applicant: Mitsubishi Electric CorporationInventors: Koichi ARISAWA, Shinya TOYODOME, Shigeo UMEHARA
-
Publication number: 20190229641Abstract: A power conversion device includes: a rectifying unit rectifying an AC voltage output from an AC power supply; a booster circuit boosting an output voltage of the rectifying unit; a control unit causing the booster circuit to perform synchronous rectification; and a smoothing capacitor smoothing an output voltage of the booster circuit. The booster circuit is constituted by connecting a plurality of chopper circuits in parallel to each other, the chopper circuits each including an upper arm switching element and a lower arm switching element connected in series to a reactor connected to the rectifying unit, and the control unit generates a drive pulse causing the upper arm switching element to be turned on when a reverse current flows through the upper arm switching element.Type: ApplicationFiled: October 13, 2016Publication date: July 25, 2019Applicant: Mitsubishi Electric CorporationInventors: Shigeo UMEHARA, Takuya SHIMOMUGI, Takashi YAMAKAWA
-
Publication number: 20190140575Abstract: A motor system according to the present invention includes: a motor including a first winding portion and a second winding portion, the second winding portion having a larger number of turns than the first winding portion; a first inverter connected to the first winding portion; and a second inverter connected to the second winding portion.Type: ApplicationFiled: June 17, 2016Publication date: May 9, 2019Inventors: Shigeo UMEHARA, Koichi ARISAWA, Yosuke SHINOMOTO, Takashi YAMAKAWA, Shinya TOYODOME
-
Publication number: 20190044469Abstract: There are provided the same number of inverter modules as the number of phases of a motor, and an inverter control unit that generates PWM signals used to drive the inverter modules in PWM. Three phase outputs from each of the inverter modules are coupled to form a phase output signal for one phase of the motor while capacitors are mounted between control GNDs of the inverter modules and power GNDs of the inverter modules. Consequently, even if a surge voltage is generated in a GND wiring at the time of a switching operation of switching elements in the inverter modules, the application of the surge voltage to the switching elements can be suppressed.Type: ApplicationFiled: April 27, 2016Publication date: February 7, 2019Inventors: Norikazu ITO, Katsuhiko SAITO, Shigeo UMEHARA, Katsuyuki AMANO, Masahiro FUKUDA
-
Patent number: 10145596Abstract: An outdoor device of an air conditioner includes a compressor, an outdoor fan, and an outdoor control board. The outdoor device includes: a control unit that controls the compressor and the outdoor fan; and a temperature detector that detects an ambient temperature of an electric component provided on the outdoor control board. The control unit, when the compressor is stopped, stops the outdoor fan and then determines whether a temperature detected by the temperature detector is equal to or higher than a threshold, and, when it is determined that the temperature detected by the temperature detector is equal to or higher than the threshold, operates the outdoor fan at a protective rotation number that is lower than a rotation number of the outdoor fan while the compressor is in operation so as to circulate air, thereby cooling the outdoor control board.Type: GrantFiled: September 4, 2015Date of Patent: December 4, 2018Assignee: Mitsubishi Electric CorporationInventor: Shigeo Umehara
-
Patent number: 9998049Abstract: An inverter control device includes an inverter main circuit, a current detector, a voltage detector that detects a DC voltage between DC bus lines, and an inverter control unit that generates PWM signals to perform on/off control of a plurality of semiconductor switching elements respectively with a DC current and a DC voltage. The unit sets a carrier period of PWM signals to be 1/N times a calculation period in which the PWM signals are generated, performs detection of a DC current detected by the current detector in a 1/2 calculation period immediately before a calculation start timing for generating PWM signals, calculates an output voltage vector based on the detected DC current, and reflects PWM signals generated from the output voltage vector in one calculation period from a 1/2 calculation period after the calculation start timing to 3/2 control calculation periods after the same.Type: GrantFiled: August 4, 2015Date of Patent: June 12, 2018Assignee: Mitsubishi Electric CorporationInventors: Mitsuo Kashima, Shigeo Umehara
-
Patent number: 9960702Abstract: A switch device in a power conversion device is located between a power supply and a load, wherein the power conversion device includes a shunt resistance and a switching element and is capable of executing stable control, the switch device includes a switching element that includes a gate terminal, a gate drive circuit that applies a drive voltage Vcc to a gate terminal of the switching element, and a control unit that generates a drive signal to the gate drive circuit, wherein a value obtained by subtracting a threshold voltage Vth of the switching element from the drive voltage Vcc to be applied to the gate terminal of the switching element is greater than a product of a resistance value Rsh+Rdc from an emitter of the switching element to a negative electrode of the gate drive circuit and a maximum current value Ipeak that flows through the switching element.Type: GrantFiled: September 25, 2013Date of Patent: May 1, 2018Assignee: Mitsubishi Electric CorporationInventors: Keisuke Uemura, Takuya Shimomugi, Koichi Arisawa, Yosuke Shinomoto, Shigeo Umehara, Shinichiro Ura, Makoto Tanikawa
-
Patent number: 9941780Abstract: A power converting apparatus includes a rectifier converting alternating-current power from an alternating-current power supply into direct-current power; a short-circuit unit short-circuiting the alternating-current power supply via a reactor; and a controlling unit controlling the short-circuit unit in a half cycle of the alternating-current power supply. A correction amount using inductance of the reactor is set in the controlling unit, and the controlling unit changes, using at least a detection value of a power supply current and the correction amount, an ON time and an OFF time of a plurality of switching pulses, and controls, using changed switching pulses, an ON/OFF operation of the short-circuit unit.Type: GrantFiled: September 30, 2014Date of Patent: April 10, 2018Assignee: Mitsubishi Electric CorporationInventors: Yuji Takayama, Takashi Yamakawa, Koichi Arisawa, Shigeo Umehara, Tomomi Higashikawa, Makoto Tanikawa
-
Publication number: 20180091079Abstract: An inverter control device includes an inverter main circuit, a current detector, a voltage detector that detects a DC voltage between DC bus lines, and an inverter control unit that generates PWM signals to perform on/off control of a plurality of semiconductor switching elements respectively with a DC current and a DC voltage. The unit sets a carrier period of PWM signals to be 1/N times a calculation period in which the PWM signals are generated, performs detection of a DC current detected by the current detector in a 1/2 calculation period immediately before a calculation start timing for generating PWM signals, calculates an output voltage vector based on the detected DC current, and reflects PWM signals generated from the output voltage vector in one calculation period from a 1/2 calculation period after the calculation start timing to 3/2 control calculation periods after the same.Type: ApplicationFiled: August 4, 2015Publication date: March 29, 2018Inventors: Mitsuo KASHIMA, Shigeo UMEHARA
-
Patent number: 9929637Abstract: The device includes a rectifier circuit that converts alternating-current power from an alternating-current power supply into direct-current power; a short-circuit unit that short-circuits the alternating-current power supply via a reactor connected between the alternating-current power supply and the rectifier circuit; and a control unit that controls an ON/OFF operation of the short-circuit unit during a half cycle of the alternating-current power supply. The control unit includes a driving-signal generating unit that generates a driving signal Sa that is a switching pulse to control the ON/OFF operation of the short-circuit unit; and a pulse dividing unit that divides the driving signal Sa into a plurality of switching pulses.Type: GrantFiled: September 26, 2014Date of Patent: March 27, 2018Assignee: Mitsubishi Electric CorporationInventors: Koichi Arisawa, Takashi Yamakawa, Yuji Takayama, Shigeo Umehara, Tomomi Higashikawa, Makoto Tanikawa
-
Patent number: 9929670Abstract: A power conversion device is configured to have reactors and is configured to have chopper circuit units, connected in series, that chop the output of a rectifier configured to rectify an AC voltage from an AC power supply. The power conversion device includes: an AC switch disposed on a side closer to the AC power supply than the chopper circuit units; an AC reactor that is connected in parallel to the AC switch; and a switching control unit that stops the switching of the switching elements when the contact of the AC switch is open.Type: GrantFiled: May 26, 2014Date of Patent: March 27, 2018Assignee: Mitsubishi Electric CorporationInventors: Michio Yamada, Takuya Shimomugi, Yosuke Shinomoto, Mitsuo Kashima, Shigeo Umehara
-
Patent number: 9866140Abstract: A power converting apparatus includes a rectifier that converts alternating-current power from an alternating-current power supply into direct-current power, a short-circuit unit that short-circuits the alternating-current power supply via a reactor, and a control unit that controls a short-circuit operation of the short-circuit unit. The control unit changes the number of times of the short-circuit operation during a half cycle of the alternating-current power supply on the basis of a load condition and sets a period from a start to an end of the short-circuit operation during the half cycle of the alternating-current power supply after the change of the number of times of the short-circuit operation to be different from a period from a start to an end of the short-circuit operation during the half cycle of the alternating-current power supply before the change of the number of times of the short-circuit operation.Type: GrantFiled: September 30, 2014Date of Patent: January 9, 2018Assignee: Mitsubishi Electric CorporationInventors: Takashi Yamakawa, Koichi Arisawa, Yuji Takayama, Shigeo Umehara, Tomomi Higashikawa, Makoto Tanikawa
-
Patent number: 9847735Abstract: A power conversion device includes a switching control unit that controls respective switching elements constituting a plurality of chopper circuits, a rectified-voltage detection unit, a bus-bar voltage detection unit, and a bus-bar current detection unit. The switching control unit includes an on-duty calculation unit that calculates a reference on-duty of respective drive pulses with respect to the switching elements based on a bus-bar voltage and a bus-bar current, an on-duty correction unit that corrects the reference on-duty to output on-duties of the respective drive pulses based on the bus-bar current, so that change amounts of respective reactor currents become substantially the same, and a drive-pulse generation unit that generates the respective drive pulses, based on the respective on-duties.Type: GrantFiled: February 26, 2013Date of Patent: December 19, 2017Assignee: Mitsubishi Electric CorporationInventors: Takuya Shimomugi, Michio Yamada, Yosuke Shinomoto, Mitsuo Kashima, Shigeo Umehara
-
Publication number: 20170302150Abstract: A power converting apparatus includes a rectifier converting alternating-current power from an alternating-current power supply into direct-current power; a short-circuit unit short-circuiting the alternating-current power supply via a reactor; and a controlling unit controlling the short-circuit unit in a half cycle of the alternating-current power supply. A correction amount using inductance of the reactor is set in the controlling unit, and the controlling unit changes, using at least a detection value of a power supply current and the correction amount, an ON time and an OFF time of a plurality of switching pulses, and controls, using changed switching pulses, an ON/OFF operation of the short-circuit unit.Type: ApplicationFiled: September 30, 2014Publication date: October 19, 2017Applicant: Mitsubishi Electric CorporationInventors: Yuji TAKAYAMA, Takashi YAMAKAWA, Koichi ARISAWA, Shigeo UMEHARA, Tomomi HIGASHIKAWA, Makoto TANIKAWA
-
Publication number: 20170288527Abstract: The device includes a rectifier circuit that converts alternating-current power from an alternating-current power supply into direct-current power; a short-circuit unit that short-circuits the alternating-current power supply via a reactor connected between the alternating-current power supply and the rectifier circuit; and a control unit that controls an ON/OFF operation of the short-circuit unit during a half cycle of the alternating-current power supply. The control unit includes a driving-signal generating unit that generates a driving signal Sa that is a switching pulse to control the ON/OFF operation of the short-circuit unit; and a pulse dividing unit that divides the driving signal Sa into a plurality of switching pulses.Type: ApplicationFiled: September 26, 2014Publication date: October 5, 2017Inventors: Koichi ARISAWA, Takashi YAMAKAWA, Yuji TAKAYAMA, Shigeo UMEHARA, Tomomi HIGASHIKAWA, Makoto TANIKAWA
-
Patent number: 9780717Abstract: A power conversion device includes an inverter configured by arms including phase upper-arm switching elements and phase lower-arm switching elements, a power-supply shunt resistor, lower-arm shunt resistors, and a control unit that generates drive signals corresponding to the phase upper-arm switching elements and the phase lower-arm switching elements from detection values of the voltage detectors. The power conversion device changes a ratio of time in which all of the upper-arm switching elements are in an ON state and time in which all of the lower-arm switching elements are in the ON state in one cycle of switching of the inverter according to a modulation ratio.Type: GrantFiled: December 3, 2013Date of Patent: October 3, 2017Assignee: Mitsubishi Electric CorporationInventors: Keisuke Uemura, Takuya Shimomugi, Koichi Arisawa, Yosuke Shinomoto, Shigeo Umehara, Shinichiro Ura, Makoto Tanikawa
-
Publication number: 20170222572Abstract: A power converting apparatus includes a rectifier that converts alternating-current power from an alternating-current power supply into direct-current power, a short-circuit unit that short-circuits the alternating-current power supply via a reactor, and a control unit that controls a short-circuit operation of the short-circuit unit. The control unit changes the number of times of the short-circuit operation during a half cycle of the alternating-current power supply on the basis of a load condition and sets a period from a start to an end of the short-circuit operation during the half cycle of the alternating-current power supply after the change of the number of times of the short-circuit operation to be different from a period from a start to an end of the short-circuit operation during the half cycle of the alternating-current power supply before the change of the number of times of the short-circuit operation.Type: ApplicationFiled: September 30, 2014Publication date: August 3, 2017Inventors: Takashi YAMAKAWA, Koichi ARISAWA, Yuji TAKAYAMA, Shigeo UMEHARA, Tomomi HIGASHIKAWA, Makoto TANIKAWA
-
Patent number: 9647604Abstract: The power conversion device includes a power-supply shunt resistance provided between an inverter and the negative-voltage side of a DC power supply, respective-phase lower-arm shunt resistances provided between the power-supply shunt resistance and respective-phase lower-arm switching elements, a first overcurrent detection unit performing overcurrent detection on a current that flows through the power-supply shunt resistance on the basis of a power-supply shunt-resistance voltage, and a second overcurrent detection unit performing overcurrent detection on each current that flows through the respective-phase lower-arm shunt resistances on the basis of respective-phase lower-arm voltages, wherein overcurrent detection is performed on each phase current using either one of the overcurrent detection result of the first overcurrent detection unit and the overcurrent detection result of the second overcurrent detection unit.Type: GrantFiled: April 8, 2013Date of Patent: May 9, 2017Assignee: Mitsubishi Electric CorporationInventors: Koichi Arisawa, Keisuke Uemura, Takuya Shimomugi, Yosuke Shinomoto, Shigeo Umehara, Shinichiro Ura, Makoto Tanikawa
-
Patent number: 9641121Abstract: A power conversion device includes a power-supply shunt resistance that is provided between an inverter and the negative-voltage side of a DC power supply, and respective-phase lower-arm shunt resistances that are provided between the power-supply shunt resistance and respective-phase lower-arm switching elements. Respective-phase lower-arm voltages, that are respective voltages between the negative-voltage side of the DC power supply and connection points between the respective-phase lower-arm switching elements and the respective-phase lower-arm shunt resistances, are detected to calculate respective-phase currents that flow through a load device in accordance with detection values of the respective-phase lower-arm voltages, and to control a carrier frequency of a carrier signal, which serves as a reference frequency of each drive signal, according to a change in a specific control parameter A.Type: GrantFiled: April 12, 2013Date of Patent: May 2, 2017Assignee: Mitsubishi Electric CorporationInventors: Takuya Shimomugi, Keisuke Uemura, Koichi Arisawa, Yosuke Shinomoto, Shigeo Umehara, Shinichiro Ura, Makoto Tanikawa
-
Patent number: 9531301Abstract: The power conversion device includes a power-supply shunt resistor provided between a negative voltage side of a DC power supply and an inverter and phase lower-arm shunt resistors respectively provided between phase lower-arm switching elements of two arms among three arms and the power-supply shunt resistor. The power conversion device detects voltages between connection points of the phase lower-arm switching elements and the phase lower-arm shunt resistors and a negative voltage side of the DC power supply and calculates, on the basis of detection values of the voltages, phase currents flowing to a load device.Type: GrantFiled: April 12, 2013Date of Patent: December 27, 2016Assignee: Mitsubishi Electric CorporationInventors: Keisuke Uemura, Takuya Shimomugi, Koichi Arisawa, Yosuke Shinomoto, Shigeo Umehara, Shinichiro Ura, Makoto Tanikawa