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:
Oct. 01, 2024
Filed:
Jun. 28, 2022
Ford Global Technologies, Llc, Dearborn, MI (US);
Ford Global Technologies, LLC, Dearborn, MI (US);
Abstract
A controller detects a rotor magnet temperature based on an actively detected back electromotive force (BEMF) voltage of the motor. The controller detects the BEMF voltage by commanding the injection of a direct-axis (d-axis) current into the motor while the motor is spinning but otherwise commanding no torque. The controller actively detects the BEMF voltage in that the controller purposely injects a known quantity of d-axis current at a chosen time during which the controller detects or is aware that the motor is commanding no torque. Using a quadrature-axis (q-axis) voltage equation, which describes the relationship between a voltage command, the current, the BEMF voltage, and reactance in the q-axis, the controller solves for the BEMF voltage with the voltage command, the current, and the q-axis reactance being known to the controller. The controller detects the rotor magnet temperature based on the BEMF voltage.