公开(公告)号：US20190310322A1

公开(公告)日：2019-10-10

申请号：US16360046

申请日：2019-03-21

Applicant: Hitachi, Ltd.

Inventor： Kazuki TANI ,  Yoshinobu KIMURA ,  Takashi OGAWA

IPC: G01R31/40 ,  H02M7/5395 ,  H02M1/088

Abstract: A power converter is provided with a power semiconductor module having a switching element. The power converter includes a gate drive circuit, a first detection unit, a second detection unit, a time measuring unit, and an abnormality diagnostic unit. The gate drive circuit drives the switching element and outputs a feedback signal based on a switching operation of the switching element. The first detection unit detects a change in a feedback signal of an upper arm of the power converter. The second detection unit detects a change in a feedback signal of a lower arm of the power converter. The time measuring unit measures a difference between detection timings of a signal change by the first detection unit and a signal change by the second detection unit. The abnormality diagnostic unit performs diagnosis of the power converter based on a measurement result by the time measuring unit.

公开(公告)号：US20190146026A1

公开(公告)日：2019-05-16

申请号：US16098599

申请日：2016-05-09

Applicant: Hitachi, Ltd.

Inventor： Yoshinobu KIMURA ,  Junichi SAKANO ,  Kimihisa FURUKAWA ,  Takashi OGAWA ,  Renichi YAMADA

IPC: G01R31/26 ,  G01K7/01 ,  B60L3/00 ,  H03M1/12

Abstract: A diagnostic system for a power conversion apparatus including a semiconductor device and performing a switching operation for carrying and interrupting a main current to a main current is disclosed. This system includes a trigger circuit that acquires reference time for the switching operation; and a delay time calculation circuit that acquires first time at which the main current takes a first main current set value and second time at which the main current takes a second main current set value, and that detects numerical data about a difference between the first time and the reference time and numerical data about a difference between the second time and the reference time.

公开(公告)号：US20210021227A1

公开(公告)日：2021-01-21

申请号：US16629328

申请日：2018-03-05

Applicant: Hitachi, Ltd.

Inventor： Yoshinobu KIMURA ,  Kazuki TANI ,  Takashi OGAWA ,  Hiroshi SUZUKI ,  Junichi SAKANO

IPC: H02P29/68 ,  H02P27/08

Abstract: A temperature abnormality of the power module is accurately detected. A power conversion device including a power semiconductor module with a switching element, includes: a gate driver circuit configured to drive a switching element and transmitting a response signal upon a switching operation of the switching element; a control unit device configured to output to a gate driver circuit an instruction signal for switching; a temperature detection unit configured to calculate a bonding temperature of the switching element based on a response signal to the instruction signal; and a calculation unit configured to determine a state of a power semiconductor module according to a bonding temperature calculated by the temperature detection unit and the response signal.

公开(公告)号：US20180138830A1

公开(公告)日：2018-05-17

申请号：US15563964

申请日：2015-04-08

Applicant: Hitachi, Ltd.

Inventor： Takashi OGAWA ,  Kimihisa FURUKAWA ,  Junichi SAKANO

IPC: H02M11/00 ,  G01R31/36 ,  G08C19/36

CPC classification number: H02M11/00 ,  G01R31/3606 ,  G01R31/44 ,  G08C19/36 ,  H02M1/08 ,  H02M1/32 ,  H02M2001/0003 ,  H02M2001/327

Abstract: The present invention relates to a power conversion device in the power electronics field. An object of the present invention is to provide a technique of determining whether a switching element operates normally or not from a gate monitor signal of a power conversion device, and predicting a sign of a failure by obtaining the temperature of the switching element from a transient state of the switching voltage of the power conversion circuit as a component of the power conversion device without using a new signal path.

公开(公告)号：US20180123477A1

公开(公告)日：2018-05-03

申请号：US15123212

申请日：2015-06-22

Applicant: HITACHI, LTD.

Inventor： Junichi SAKANO ,  Kimihisa FURUKAWA ,  Takashi OGAWA ,  Hisashi ENDOU

IPC: H02M7/539 ,  H02M1/32

CPC classification number: H02M7/539 ,  H02M1/32 ,  H02M7/48 ,  H02M7/53 ,  H02M2001/0009 ,  H02M2001/0012 ,  H02M2001/327

Abstract: There is provided a diagnostic system for a power converter which includes a semiconductor device, and performs a switching operation between conduction and interruption of the principal current flowing through the main circuit. The diagnostic system includes a current change amount calculation circuit for obtaining numeric data which reflects a current change amount of the principal current per unit time, a determination circuit for determining a state of the power converter by comparing the numeric data with a reference value, and an output circuit for outputting a determination result of the determination circuit.