Reduced transient model of a group of induction motors

The linear model representing a group of induction motors, assumed to run at constant speeds during a short period following a disturbance, is reduced by building a lower order model using only the dominant eigenvalues of the complete model. The choice of the eigenvalues to be retained is discussed and the accuracy of the reduced model is assessed by comparing the step responses of the reduced and complete models. Groups of up to 29 motors are considered and it is shown that reasonably accurate models, of less than a quarter of the original order, are possible