A Generalized And Simplified Transient Torque Analysis For Synchronous Motor Drive Trains.

Abstract

The start-up of synchronous motor drive trains is usually associated with torsionally excited vibrations and low-cycle fatigue problems. Traditional calculation methods used for analysis of such a system involve computerized integrations with very small time steps and many degrees of freedom. A simple method is presented herein which uses the knowledge of system natural frequencies and mode shapes and a general dimensionless integration data plot. A sample problem is included to demonstrate the application of the method. The results are compared with the more rigorous, traditional method to illustrate the accuracy of the simplified method. A procedure is also included to relate the dynamic torque to the torsional low-cycle fatigue limit, thus establishing a safe number of starts.