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:
Mar. 10, 2015
Filed:
Apr. 01, 2009
Theerawat Limpibunterng, Susono, JP;
Takahiro Kojo, Gotenba, JP;
Theerawat Limpibunterng, Susono, JP;
Takahiro Kojo, Gotenba, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
An ECU executes steering control in a vehicle including an electronic control power steering apparatus. In the steering control, it is determined that an assist motor is in a power generating state when a motor rotation speed ω which is the rotation speed of the assist motor is greater than an upper limit rotation speed ωset according to a motor command voltage Vq that is the driving voltage of the assist motor. When the assist motor is in the power generating state, the ECU interrupts the supply of current to the assist motor by controlling a relay portion of a drive apparatus that drives the assist motor so that it is open, thereby reducing the amount of power that is generated to zero. Also, when returning to an assist possible state, assist torque Tm is changed gradually with zero as the initial value in order to prevent it from changing suddenly.