54 results about "Commutation torque ripple" patented technology

The present invention discloses a novel low-commutation torque ripple brushless direct-current motor. The novel low-commutation torque ripple brushless direct-current motor comprises a direct-current motor and a sensor device; the direct-current motor comprises a first stator, a first rotor, first rotor magnetic steel and a rear end cover; the sensor device comprises a second stator, a second rotor, an annular magnet and a sensor integrated circuit; the second stator is annular and is corresponding to the first rotor; the second rotor and the first rotor rotate coaxially and synchronously; the periphery of the second rotor is provided with the annular magnet; the sensor integrated circuit is fixed onto the inner peripheral surface of the second stator; the sensor integrated circuit comprises position sensors for collecting the position signals of the second rotor; the position sensors are mounted in hysteresis mounting positions; and the hysteresis mounting positions are obtained by forwardly moving an optimal commutation position along the forward direction of the rotation of the second rotor by 5 to 10 degrees. According to the novel low-commutation torque ripple brushless direct-current motor of the invention adopted, electromagnetic torque ripples generated during the commutation process of the brushless direct-current motor can be decreased, the torque performance of the motor can be improved, and the installation difficulty of a Hall sensor can be reduced.

The invention discloses a method for a brushless direct current motor, which belongs to the technical field of electric power transmission. In the present invention, a front-stage four-output level power converter is cascaded with a rear-stage two-level three-phase full-bridge inverter as a power supply topology for a brushless DC motor, and instantaneous current is used as a control variable. The instantaneous current is controlled to always track the reference value by constantly switching the output level of the front-stage four-output-level power converter, and the commutation of the brushless DC motor is performed through the switch state of the rear-stage three-phase full-bridge inverter. The method can reduce the current harmonic generated by PWM control, improve the dynamic response speed and effectively suppress the commutation torque ripple at a lower switching frequency.

The invention discloses a BSRMWR torque ripple suppression method based on turn-on and turn-off angle control. A suitable turn-off angle is selected in the swap-out phase, and an appropriate turn-on angle is selected in the swap-in phase, so as to optimize the current rise and fall between the commutation phases. speed purpose, thereby suppressing or eliminating commutation torque ripple. The method is simple and practical, and can improve the dynamic performance of the system. The coupling problem between the torque and the levitation force of the traditional bearingless switched reluctance motor is solved; the method selects the appropriate turn-on angle and turn-off angle to improve the torque and levitation force performance of the motor. The method of the invention is simple and practical, convenient to control, and can enhance the reliability and stability of the motor system.