DEVICE TO MEASURE COGGING TORQUE FOR ROTATORS

摘要

When measuring the cogging torque of a test motor from a q-axis current generated by a driving motor when bypassing a torque sensor and directly connecting the test motor to and driving the same with the driving motor, first the q-axis current of the driving motor operating without a load is measured separately under the cogging torque measurement conditions. This q-axis current without a load is subtracted from the q-axis current with a load provided when the test motor is directly connected to and driven by the driving motor and operated under a load so as to remove the q-axis current component caused by the driving motor superimposed as a disturbance. Therefore, a sufficient degree of accuracy can be ensured in the measured value for cogging torque without selectively using as the driving motor a motor having a structure for which the cogging torque component is ideally zero, such as coreless or slotless motors.