Patents by Inventor Shuji Katoh
Shuji Katoh 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: 20130279227Abstract: The present invention provides an inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor, and provides power equipment as well as a power converting apparatus. The inter-bus-bar built-in capacitor is provided between a pair of opposing bus bars and includes a high-dielectric-constant material which has a relative dielectric constant of at least 50 when a voltage of 1,000 V is applied at a temperature of 25° C. Thus, it is possible to provide the inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor and provide the power equipment as well as the power converting apparatus.Type: ApplicationFiled: October 11, 2011Publication date: October 24, 2013Applicant: HITACHI ,LTD.Inventors: Yuichiro Yoshitake, Shuji Katoh, Hiroshi Morita, Atsushi Ootake
-
Patent number: 8547718Abstract: A power converter apparatus having a configuration of a plurality of unit cells, including a DC capacitor and semiconductor devices, connected in cascade, includes a variable voltage source that is connected with a DC link, and a unit having a function that initially charges up the DC capacitor in the unit cell alone selected at a time of an initial charge.Type: GrantFiled: July 20, 2010Date of Patent: October 1, 2013Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Shigenori Inoue
-
Patent number: 8213146Abstract: A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series.Type: GrantFiled: August 27, 2010Date of Patent: July 3, 2012Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Toshihiko Matsuda, Takashi Ikimi, Hiroshi Nagata
-
Publication number: 20120113698Abstract: Disclosed is a power conversion device, wherein among the optical fiber cables used in control/communication, at least the majority of high-voltage optical fiber cables with a dielectric strength against the output voltages of a plurality of cells can be eliminated and thus a low-voltage optical fiber cable with a dielectric strength against the output voltage of one cell can be used. Furthermore, here, the length required for the optical fiber cable can be reduced. A controller of the power conversion device comprising a plurality of cascade-connected cells comprises a central controller, and a cell controller with the same potential as each cell, the cell controller being installed in the vicinity of each cell, wherein the central controller and each cell controller are daisy-chained using an optical fiber cable.Type: ApplicationFiled: July 13, 2010Publication date: May 10, 2012Inventors: Shigenori Inoue, Shuji Katoh, Tetsuya Kato
-
Publication number: 20120026767Abstract: A power conversion device connected with a three-phase power system through a transformer, including unit converters cascade-connected so that reactors are unnecessary, and volume and weight are reduced. The secondary winding of the transformer is an open winding having six terminals. A first converter group, includes a circuit which has three converter arms, which are star-connected, connected to three of the terminals of the secondary winding. A second converter group, having three different converter arms which are star-connected, is connected to three other terminals of the secondary winding. A neutral point (the point where the star connection is made) of the first converter group, and a neutral point of the second converter group are made to be the output terminals of the power conversion device.Type: ApplicationFiled: February 24, 2010Publication date: February 2, 2012Inventors: Shigenori Inoue, Shuji Katoh, Jun Narushima, Tetsuya Kato
-
Publication number: 20110019449Abstract: A power converter apparatus having a configuration of a plurality of unit cells, including a DC capacitor and semiconductor devices, connected in cascade, includes a variable voltage source that is connected with a DC link, and a unit having a function that initially charges up the DC capacitor in the unit cell alone selected at a time of an initial charge.Type: ApplicationFiled: July 20, 2010Publication date: January 27, 2011Inventors: Shuji Katoh, Shigenori Inoue
-
Publication number: 20110019442Abstract: The noise generated from a power converter is suppressed by increasing the noise frequency to a level not lower than the maximum frequency of the human audible range. To obtain the frequency of an output current harmonic component as a noise source which has exceeded the maximum frequency of the human audible range, it is adequate to determine that the frequency of a driving carrier wave for the individual converter cells in the power converter, in which the phases of the carrier wave for the converter cells are mutually shifted by a given value between the converter cells, meets the following equation.Type: ApplicationFiled: July 20, 2010Publication date: January 27, 2011Inventors: Yoichiro YAMADA, Shuji KATOH, Shigenori INOUE
-
Publication number: 20100321847Abstract: A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series.Type: ApplicationFiled: August 27, 2010Publication date: December 23, 2010Inventors: Shuji KATOH, Toshihiko MATSUDA, Takashi IKIMI, Hiroshi NAGATA
-
Patent number: 7643317Abstract: In a system to which a fluctuating load is connected, compensating for fluctuation in voltage harmonics at the load connecting point and fluctuation in system current harmonics has been difficult for a power converting device connected in parallel with the load. To resolve the problem, a power converting device connected in parallel with a fluctuating load includes: a Fourier series expansion unit which executes Fourier series expansion to load current by use of a reference sine wave in sync with a system and thereby outputs Fourier coefficients; and a fundamental component calculating unit which calculates a positive phase active fundamental component of the load current from the Fourier coefficients. A current instruction of the power converting device is generated by subtracting the fundamental current from the load current. With the current instruction, the fluctuations in system current harmonics and in voltage harmonics at the connecting point can be compensated for.Type: GrantFiled: December 26, 2007Date of Patent: January 5, 2010Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Yasuhiro Kiyofuji, Shoichiro Koseki, Tomomichi Ito, Motoo Futami
-
Publication number: 20090168474Abstract: In a system to which a fluctuating load is connected, compensating for fluctuation in voltage harmonics at the load connecting point and fluctuation in system current harmonics has been difficult for a power converting device connected in parallel with the load. To resolve the problem, a power converting device connected in parallel with a fluctuating load includes: a Fourier series expansion unit which executes Fourier series expansion to load current by use of a reference sine wave in sync with a system and thereby outputs Fourier coefficients; and a fundamental component calculating unit which calculates a positive phase active fundamental component of the load current from the Fourier coefficients. A current instruction of the power converting device is generated by subtracting the fundamental current from the load current. With the current instruction, the fluctuations in system current harmonics and in voltage harmonics at the connecting point can be compensated for.Type: ApplicationFiled: December 26, 2007Publication date: July 2, 2009Inventors: Shuji Katoh, Yasuhiro Kiyofuji, Shoichiro Koseki, Tomomichi Ito, Motoo Futami
-
Patent number: 6891214Abstract: A semiconductor power module capable of efficiently utilizing the performance of the module and facilitating management of the module in custody. The semiconductor power module having one or more semiconductor power switching elements and a drive unit is provided with a non-volatile memory for storing use history of the module and a drive unit. The use history contains information of one of the number of switching times of the semiconductor power switching element, the number of over-current detections of the semiconductor power switching element and a temperature rise of the semiconductor power module.Type: GrantFiled: March 13, 2002Date of Patent: May 10, 2005Assignee: Hitachi, Ltd.Inventors: Kazuhisa Mori, Takashi Ikimi, Shuji Katoh, Yutaka Sato
-
Patent number: 6839213Abstract: A semiconductor power module capable of efficiently utilizing the performance of the module and facilitating management of the module in custody. The semiconductor power module having one or more semiconductor power switching elements and a drive unit is provided with a non-volatile memory for storing use history of the module and a drive unit. The use history contains information of one of the number of switching times of the semiconductor power switching element, the number of over-current detections of the semiconductor power switching element and a temperature rise of the semiconductor power module.Type: GrantFiled: August 7, 2002Date of Patent: January 4, 2005Assignee: Hitachi, Ltd.Inventors: Kazuhisa Mori, Takashi Ikimi, Shuji Katoh, Yutaka Sato
-
Patent number: 6809561Abstract: A semiconductor power converting apparatus including at least one series arrangement of MOS control semiconductor devices such as Insulator-gate Bipolar Transistors (IGBTs) or metal oxide MOS transistors which are respectively applied with a gate voltage under the control of corresponding a driver. The driver contains a supply line having a higher potential than a gate voltage of an IGBT coupled thereto when the IGBT is in a steady ON state, and is such that is causes an increase of the gate voltage of the IGBT in accordance with the current of the supply line when a potential difference between the power supply line and an emitter of the IGBT is constant and the collector voltage thereof exceeds a predetermined value under an ON state of the IGBT.Type: GrantFiled: August 12, 2003Date of Patent: October 26, 2004Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Patent number: 6727516Abstract: A power conversion apparatus has a circuit configuration in which a collector voltage of an IGBT is divided. It also has a unit which protects the IGBT against overvoltages applied to the collector by outputting a potential of a voltage dividing point to a gate of the IGBT. A case of a resistor on the high-voltage side of the voltage dividing point is fixed to an emitter potential of the IGBT.Type: GrantFiled: March 12, 2002Date of Patent: April 27, 2004Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Patent number: 6717177Abstract: A power conversion apparatus has a circuit configuration in which a collector voltage of an IGBT is divided. It also has a unit which protects the IGBT against overvoltages applied to the collector by outputting a potential of a voltage dividing point to a gate of the IGBT. A case of a resistor on the high-voltage side of the voltage dividing point is fixed to an emitter potential of the IGBT.Type: GrantFiled: March 28, 2003Date of Patent: April 6, 2004Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Patent number: 6703874Abstract: A gate driver is provided for controlling a gate voltage of each of a plurality of MOS control semiconductor devices, such as IGBTs or metal oxide MOS transistors, of a semiconductor power converter in which said MOS control semiconductors are connected in series with each other, the gate driver includes a power supply line having a higher potential than a gate potential on each of said MOS control semiconductor devices when in steady ON state, and an arrangement for supplying a current from the power source line to the gate of each of said MOS control semiconductors to increase the gate voltage of the MOS control semiconductor devices when a potential difference between said power supply line and an emitter of each of said MOS control semiconductors is constant and when a collector voltage of the MOS control semiconductor device exceeds a predetermined value under ON state of the MOS control semiconductor device.Type: GrantFiled: May 13, 2003Date of Patent: March 9, 2004Assignee: Hitachi, Ltd.Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Publication number: 20040027193Abstract: To avoid that IGBTs are destroyed by receiving overvoltages while an overcurrent flows through series-connected IGBTs of a semiconductor power converting apparatus, a gate driver for controlling a gate voltage of the MOS control semiconductor owns a power supply line having a higher potential than such a gate potential when the MOS control semiconductor is brought into a steady ON state, and when a potential difference between the power supply line and an emitter of the MOS control semiconductor is constant, and also a collector voltage of the MOS control semiconductor exceeds a predetermined value under ON state of the MOS control semiconductor, the power source line of the gate driver supplies a current from the power source line to the gate of the MOS control semiconductor so as to increase the gate voltage of the MOS control semiconductor.Type: ApplicationFiled: August 12, 2003Publication date: February 12, 2004Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Publication number: 20030201516Abstract: A power conversion apparatus has a circuit configuration in which a collector voltage of an IGBT is divided. It also has a unit which protects the IGBT against overvoltages applied to the collector by outputting a potential of a voltage dividing point to a gate of the IGBT. A case of a resistor on the high-voltage side of the voltage dividing point is fixed to an emitter potential of the IGBT.Type: ApplicationFiled: March 28, 2003Publication date: October 30, 2003Applicant: HITACHI, LTD.Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Publication number: 20030197533Abstract: A gate driver is provided for controlling a gate voltage of each of a plurality of MOS control semiconductor devices, such as IGBTs or metal oxide MOS transistors, of a semiconductor power converter in which said MOS control semiconductors are connected in series with each other, the gate driver includes a power supply line having a higher potential than a gate potential on each of said MOS control semiconductor devices when in steady ON state, and an arrangement for supplying a current from the power source line to the gate of each of said MOS control semiconductors to increase the gate voltage of the MOS control semiconductor devices when a potential difference between said power supply line and an emitter of each of said MOS control semiconductors is constant and when a collector voltage of the MOS control semiconductor device exceeds a predetermined value under ON state of the MOS control semiconductor device.Type: ApplicationFiled: May 13, 2003Publication date: October 23, 2003Inventors: Shuji Katoh, Shigeta Ueda, Hiromitsu Sakai, Takashi Ikimi, Tomomichi Ito
-
Publication number: 20030057468Abstract: A semiconductor power module capable of efficiently utilizing the performance of the module and facilitating management of the module in custody. The semiconductor power module having one or more semiconductor power switching elements and a drive unit is provided with a non-volatile memory for storing use history of the module and a drive unit. The use history contains information of one of the number of switching times of the semiconductor power switching element, the number of over-current detections of the semiconductor power switching element and a temperature rise of the semiconductor power module.Type: ApplicationFiled: March 13, 2002Publication date: March 27, 2003Applicant: Hitachi, Ltd.Inventors: Kazuhisa Mori, Takashi Ikimi, Shuji Katoh, Yutaka Sato