公开(公告)号：JP2001008495A

公开(公告)日：2001-01-12

申请号：JP2000123299

申请日：2000-04-24

Applicant: INT RECTIFIER CORP

Inventor： DUBHASHI AJIT ,  BERTRAND VEISE

IPC: H02M1/12 ,  H02M1/14 ,  H02M1/44 ,  H02M5/45 ,  H02M7/00 ,  H02P23/00 ,  H02P7/36 ,  H02M7/48

Abstract: PROBLEM TO BE SOLVED: To reduce transmission and radiation EMI in a motor drive application by inserting an inductor into the ground line of a motor drive circuit. SOLUTION: In a motor drive circuit 40, inductors 42 and 44 are inserted into a ground line 46. High frequency current flowing in the loop is reduced, a ground loop area on a printed board is narrowed, and therefore radiation EMI is reduced. A power device is capacitively coupled to a heat sink and current generated by capacitive coupling flows and is returned to a heat sink connection. Thus, transmission and radiation EMI in a motor drive application can be reduced.