Abstract：The synchronization accuracy of a multi-motor speed synchronization system is influenced by the

motor control algorithm and synchronization control strategy. In response to the shortcomings of existing control

strategies，a mid-range deviation coupling control strategy for multi-motor speed synchronization systems was

proposed. Firstly，a mathematical model of multi permanent magnet synchronous motor was established. On the

basis of the deviation coupling control strategy，the motor speed deviation was calculated using mid-range speed，

and the structure of the deviation coupling control was optimized. The controller was designed using a nonsingular

Terminal sliding mode control algorithm. Then，the Lyapunov stability theory was used to analyze the stability of

the designed controller. Finally，a multi-motor synchronous control test platform was established for test

verification，and the test data was analyzed. The results show that the proposed control strategy is effective and can

improve the synchronization performance of the system.

      Key words：multi-motor speed synchronization system；mid-range deviation coupling control（MDCC）；

nonsingular Terminal sliding mode control