Estimation of Motor Excitation Force by Indirect Method

Abstract

We developed two methods for accurate estimation of the excitation force of a motor. One is a hybrid method combining an experiment and a finite-element analysis. In the experiment, the circumferential acceleration of a motor housing was measured when the motor was in operation. Additionally, a finite-element model was created for the motor, and the circumferential acceleration response of this model was calculated. The measured and calculated accelerations were then used to estimate the motor excitation force. The other method is an elastic support method using the measured acceleration response. The amplitude and phase of excitation forces were estimated by solving an inverse dynamical problem that used as input the acceleration measured by accelerometers placed on the supporting beams of the motor. The results obtained by these methods agreed well with the excitation force measured by using load cell.