Synchronization and coordination control based on enhanced deviation coupling for multi-motor rigid connection systems

Abstract The operational performances of the conventional controlled multi-motor drive systems are affected by the parameters of the motor, sudden load changes, and external disturbances. These factors may cause issues such as motor speed loss and torque imbalance, with severe cases potentially resulting in motor shaft fractures. In this paper, an enhanced deviation coupling-based synchronization and coordination control method is proposed for multi-motor rigid connection systems. The monomer and gear structure of the induction motor are modeled, respectively, and the transfer functions are given to analyze the factors that affect speed unsynchrony and torque uncoordination for the multi-motor systems. The inherent shortcomings of simple deviation coupling control are clarified, which makes it difficult to achieve the speed synchronization and torque balance of the multi-motor systems. An enhanced deviation coupling control method that simultaneously compensates for speed and torque is designed, and its stability is analyzed. Compared with the deviation coupling control method, the experimental results show that the proposed control method effectively reduces the speed synchronization errors and suppresses the torque output fluctuation. The control system has better performance of real-time and robustness.