Texas Instruments Corporation

Brian Lee Schmidt

John Kevin Rote

Gregory Swize

Seil Oh

A quiet motor control system is described. This system digitally determines modulated voltages applied to motor phases in a manner that compensates for winding torque distortions, which reduces acoustic emissions.

Quiet motor control system

To achieve peak acoustic and power performance, the coil or applied current should be in phase or substantially aligned with the back electromotive force (back-EMF) voltage. However, there are generally phase differences between the applied current and back-EMF voltage that are induced by the impedance of the brushless DC motor (which can vary based on conditions, such as temperature and motor speed). Traditionally, compensation for these phase differences was provided manually and on an as-needed basis. Here, however, a system and method are provided that automatically perform a commutation advance by incrementally adjusting a drive signal over successive commutation cycles when the applied current and back-EMF voltage are misaligned.

Growing community of inventors

Sachse, TX, United States of America

Brian Lee Schmidt