Conditions for stable synchronization of three and more motors mounted on one foundation

The paper studies problems of stability of synchronization conditions for nonlinear systems, which occur spontaneously during operation of three and more electric motors fixed on one foundation, where their rotors are unbalanced, and conditions excluding synchronization. The paper considers systems of three motors. Necessary and sufficient conditions for synchronization are revealed. Problem of stable synchronization occurs in rail transport, where several motors work simultaneously in different modes.