Patents by Inventor Agnes HADINATA
Agnes HADINATA 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: 11575338Abstract: This power conversion device comprises: a power converter including a switching element; and a control unit which controls the power converter. The control unit calculates a torque electric current detection value and an excitation electric current detection value from an electric current flowing to an external device, and when an absolute value of the torque electric current detection value is greater than or equal to the excitation electric current detection value, performs control such that the excitation electric current detection value follows the torque electric current detection value.Type: GrantFiled: April 28, 2020Date of Patent: February 7, 2023Assignee: Hitachi Industrial Equipment Systems Co., Ltd.Inventors: Kazuaki Tobari, Agnes Hadinata, Atsuhiko Nakamura, Hiroshi Watanabe, Yusaku Onuma, Takuya Sugimoto, Yoshiyuki Taguchi
-
Patent number: 11437944Abstract: A power conversion device includes a harmonic voltage generation unit that superimposes dc-axis and qc-axis harmonic voltages on dc-axis and qc-axis voltage commands in accordance with a switching signal; and an inductance estimation unit that estimates dc-axis inductance and qc-axis inductance on a basis of dc-axis and qc-axis harmonic currents, amplitude values of the harmonic voltages, and the switching signal.Type: GrantFiled: May 29, 2019Date of Patent: September 6, 2022Assignee: Hitachi Industrial Equipment Systems Co., Ltd.Inventors: Kazuaki Tobari, Yoshitaka Iwaji, Agnes Hadinata, Yusaku Onuma, Takuya Sugimoto, Atsuhiko Nakamura, Hiroshi Watanabe, Yoshiyuki Taguchi
-
Patent number: 11424707Abstract: A power conversion apparatus controls a load apparatus by position sensorless vector control. The power conversion apparatus includes: a current detection unit configured to detect a current passing through the load apparatus; a current detection arithmetic unit configured to calculate a harmonic current component on a dc-axis as a control axis and a harmonic current component on a qc-axis, based on the detected current; a saliency ratio estimation unit configured to output a saliency ratio estimated value based on the harmonic current component on the dc-axis and the harmonic current component on the qc-axis; and a saliency ratio control unit configured to output a current component that increases or decreases a current command value on a d-axis of a rotor coordinate system, based on a deviation between the saliency ratio estimated value and a predetermined saliency ratio.Type: GrantFiled: December 26, 2018Date of Patent: August 23, 2022Assignee: HITACHI INDUSTRIAL EQUIPMENT SYSTEMS CO., LTD.Inventors: Kazuaki Tobari, Yoshitaka Iwaji, Agnes Hadinata, Yusaku Onuma, Atsuhiko Nakamura, Takuya Sugimoto
-
Publication number: 20220094291Abstract: This power conversion device comprises: a power converter including a switching element; and a control unit which controls the power converter. The control unit calculates a torque electric current detection value and an excitation electric current detection value from an electric current flowing to an external device, and when an absolute value of the torque electric current detection value is greater than or equal to the excitation electric current detection value, performs control such that the excitation electric current detection value follows the torque electric current detection value.Type: ApplicationFiled: April 28, 2020Publication date: March 24, 2022Inventors: Kazuaki TOBARI, Agnes HADINATA, Atsuhiko NAKAMURA, Hiroshi WATANABE, Yusaku ONUMA, Takuya SUGIMOTO, Yoshiyuki TAGUCHI
-
Publication number: 20210273591Abstract: A power conversion device includes a harmonic voltage generation unit that superimposes dc-axis and qc-axis harmonic voltages on dc-axis and qc-axis voltage commands in accordance with a switching signal; and an inductance estimation unit that estimates dc-axis inductance and qc-axis inductance on a basis of dc-axis and qc-axis harmonic currents, amplitude values of the harmonic voltages, and the switching signal.Type: ApplicationFiled: May 29, 2019Publication date: September 2, 2021Inventors: Kazuaki TOBARI, Yoshitaka IWAJI, Agnes HADINATA, Yusaku ONUMA, Takuya SUGIMOTO, Atsuhiko NAKAMURA, Hiroshi WATANABE, Yoshiyuki TAGUCHI
-
Publication number: 20210152113Abstract: A power conversion apparatus controls a load apparatus by position sensorless vector control. The power conversion apparatus includes: a current detection unit configured to detect a current passing through the load apparatus; a current detection arithmetic unit configured to calculate a harmonic current component on a dc-axis as a control axis and a harmonic current component on a qc-axis, based on the detected current; a saliency ratio estimation unit configured to output a saliency ratio estimated value based on the harmonic current component on the dc-axis and the harmonic current component on the qc-axis; and a saliency ratio control unit configured to output a current component that increases or decreases a current command value on a d-axis of a rotor coordinate system, based on a deviation between the saliency ratio estimated value and a predetermined saliency ratio.Type: ApplicationFiled: December 26, 2018Publication date: May 20, 2021Inventors: Kazuaki TOBARI, Yoshitaka IWAJI, Agnes HADINATA, Yusaku ONUMA, Atsuhiko NAKAMURA, Takuya SUGIMOTO
-
Patent number: 10903767Abstract: According to the present invention, in position sensorless control for switching between a 120-degree energization scheme for a low-speed region and a 180-degree energization scheme for a mid-to-high-speed region, stable and highly accurate speed control characteristics are provided by suppressing speed deviation ??r in the low-speed region, and by preventing current jump-up caused by a discontinuous rotational speed occurring during switching to the mid-to-high-speed region. In the case of driving in the 120-degree energization scheme, a voltage command value is corrected such that an estimated speed value or a detected speed value follows a speed command.Type: GrantFiled: March 2, 2018Date of Patent: January 26, 2021Assignee: Hitachi Industrial Equipment Systems Co., Ltd.Inventors: Agnes Hadinata, Yoshitaka Iwaji, Kazuaki Tobari, Yusaku Onuma, Takuya Sugimoto, Masato Ohya
-
Publication number: 20200052620Abstract: According to the present invention, in position sensorless control for switching between a 120-degree energization scheme for a low-speed region and a 180-degree energization scheme for a mid-to-high-speed region, stable and highly accurate speed control characteristics are provided by suppressing speed deviation ??r in the low-speed region, and by preventing current jump-up caused by a discontinuous rotational speed occurring during switching to the mid-to-high-speed region. In the case of driving in the 120-degree energization scheme, a voltage command value is corrected such that an estimated speed value or a detected speed value follows a speed command.Type: ApplicationFiled: March 2, 2018Publication date: February 13, 2020Inventors: Agnes HADINATA, Yoshitaka IWAJI, Kazuaki TOBARI, Yusaku ONUMA, Takuya SUGIMOTO, Masato OHYA
-
Patent number: 9973101Abstract: A power conversion circuit uses a multiphase AC power source as an input and has a plurality of bidirectional switches each of which is connected to each phase of the multiphase AC power source. A switching control circuit controls the states of the plurality of bidirectional switches and switches a combination of two phases of the multiphase AC power source, relating to interphase voltage to be outputted from the power conversion circuit to a load side. A resonant circuit is connected to an output side of the power conversion circuit. The switching control circuit, at a time of switching of the combination of the two phases that output the interphase voltage to the load side, switches the states of the bidirectional switches relating to the switching, by soft switching.Type: GrantFiled: January 27, 2015Date of Patent: May 15, 2018Assignees: NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY, Omrom CorporationInventors: Satoshi Ogasawara, Agnes Hadinata, Takashi Hyodo
-
Publication number: 20160352238Abstract: A power conversion circuit uses a multiphase AC power source as an input and has a plurality of bidirectional switches each of which is connected to each phase of the multiphase AC power source. A switching control circuit controls the states of the plurality of bidirectional switches and switches a combination of two phases of the multiphase AC power source, relating to interphase voltage to be outputted from the power conversion circuit to a load side. A resonant circuit is connected to an output side of the power conversion circuit. The switching control circuit, at a time of switching of the combination of the two phases that output the interphase voltage to the load side, switches the states of the bidirectional switches relating to the switching, by soft switching.Type: ApplicationFiled: January 27, 2015Publication date: December 1, 2016Applicants: NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSIT Y, Omron CorporationInventors: Satoshi OGASAWARA, Agnes HADINATA, Takashi HYODO