Torsional analysis and coupling selection for electric machine coupled to reciprocating equipment

Electric machines and reciprocating equipment are very efficient, flexible, and have wide range of applications. Trains including electric and reciprocating machines are subject to the most varied and often most severe torsional disturbances in comparison to other machinery classes. If shaft or rotating component failures occur as a result of shaft torsional oscillations, the consequences can be catastrophic. In this paper a comprehensive model and solutions using analytical formulations are developed to study both steady state and transient response of complex reciprocating and electrical trains. Analytical results are presented and recommendations for torsional reliable trains are addressed. Couplings being the more accessible components within the train are often modified to tune the overall system. Recommendations for coupling: High torsional stiffness coupling (if allowed by torsional analysis), or flexible coupling or integral rigid forged flange connection with single bearing electric machine.