The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 2017
Filed:
Sep. 12, 2014
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, Ibaraki, JP;
Masaki Hano, Isesaki, JP;
Takeshi Umetsu, Isesaki, JP;
HITACHI AUTOMOTIVE SYSTEMS, LTD., Hitachinaka-shi, JP;
Abstract
When a set duty Dt of a PWM signal is less than a minimum duty (Dmin) that allows for pulse induced voltage detection, the PWM signal in which a duty Dduring a predetermined period is limited to Dmin and in which a duty Dduring the other period is adjusted so as to satisfy Dt=(D+D)/2 is applied to the switching elements connected to one of the two phases. When the duty Dduring the other period takes a negative value, the pulse-voltage application target during the other period is changed to the switching elements connected to the other of the two phases, and the duty Dduring the predetermined period is corrected and increased so as to compensate for an actual drop in the duty Dduring the other period corresponding to a dead-time period in a complementary PWM method.