A Compound Control Strategy of Torque Ripple Reduction for BLDC motor

The existence of torque ripple greatly limits the application of brushless dc motor in the high precision field. To abate the torque ripple of motor applied in aircraft fuel pump, a compound control strategy is proposed. Aiming at the torque ripple created by imperfect back EMF, a reference current calculation method considering the actual back EMF is put forward. The back EMF is obtained through the extended Kalman filter observer and the reference current is calculated with the observations. For the commutation torque ripple, a current following method whose basis is the current predictive control is employed during commutation. The non-commutation phase is set to always open. The duty cycles of other two phases are calculated for maintaining the non-commutation phase current following the reference. The simulation outcomes signify that the compound control strategy is capable of restraining the torque ripple efficiently.