公开(公告)号：US11609267B2

公开(公告)日：2023-03-21

申请号：US17455580

申请日：2021-11-18

Applicant: Hitachi, Ltd.

Inventor： Isao Houda ,  Aya Ohmae ,  Umberto Paoletti

IPC: G01R31/309 ,  H05K1/02 ,  G01R1/067

Abstract: Provided is an immunity evaluation system that enables design feedback in consideration of a subject wiring and an improvement amount for improving an electromagnetic noise resistance of a circuit board. An immunity evaluation device includes: a storage unit configured to store characteristic data including probe-circuit board wiring coupling characteristics which are determined by a combination of a near-field probe and circuit board characteristics, and a test result; and an IC reaching signal level estimation unit configured to estimate a signal level reaching a terminal of an evaluation target IC. The immunity evaluation device receives board design information, information of the near-field probe, and test waveform instruction information of a signal applied to the near-field probe. The IC reaching signal level estimation unit reads the coupling characteristics from the storage unit based on the board design information of a test subject circuit board and the information of the near-field probe, and outputs a value of the IC reaching signal level reaching a terminal of the evaluation target IC from the board design information of the test subject circuit board, the information of the near-field probe, and the coupling characteristics.

公开(公告)号：US10160334B2

公开(公告)日：2018-12-25

申请号：US15121310

申请日：2014-12-08

Applicant: Hitachi, Ltd.

Inventor： Isao Houda ,  Masayoshi Takahashi ,  Hiroki Funato ,  Hitoshi Akiyama

IPC: H02M3/156 ,  B60L11/18 ,  H02M1/44 ,  H02M7/44 ,  H02P27/08

Abstract: Provided is a power conversion device capable of selectively suppressing harmonic noise in a frequency band and a machine equipped with the power conversion device. The power conversion device includes a switching element (13), a switching signal generation unit (23, 24) for generating a switching control signal for controlling the turning on/off of the switching element (13), and a control unit (18), and is characterized in that the switching control signal generation unit (23, 24) generates the switching control signal including a combination of a pair of symmetrical pulse waveforms having on and off periods that are interchanged with respect to a repeated cycle.