METHOD FOR REDUCTING TORQUE RIPPLE BY COMPENSATING CONTROL OF POSITION ERROR

摘要

A method is provided to reduce a torque ripple of an electric motor generated by the position error and make it possible to control current. A position angle(thetar) is sensed using a resolver(S10). A position angle(thetastr) is sensed for compensating for a position error component by using a position sensor(S20). When the position angle sensed by the position sensor is the same as an actual position angle of a rotator, the components are calculated based on a sinusoid table(S30). -sin Deltatheta and -cos Deltatheta are calculated by converting the calculated components from step (S30) into distorted T(thetar) or T(theta+Deltatheta)(S40). A current instruction value of a d-q synchronous frame is changed and the changed current instruction value is applied to a current controller(S50). The d-q synchronous frame is changed into a d-q stationary frame, by reflecting the distorted position angle Deltatheta component in the current instruction value of the d-q synchronous frame(S60).