Speed synchronization of multiple induction motors with adjacent cross coupling control

In this paper, a new control approach for real time speed synchronization of multiple induction motors during speed acceleration and load changes is developed. The control strategy is to stabilize speed tracking of each motor while synchronizing its motion with other motors´ motions so that differential speed errors amongst multiple motors converge to zero. An adjacent cross coupling control architecture incorporating sliding mode control method is proposed, and the asymptotic convergence to zero of both speed tracking errors and synchronization errors have been realized via Lyapunov stability analysis. A sliding mode flux observer is adopted to implement direct field orientation of an induction motor with high robustness. Simulations conducted on a multiple motors system demonstrate the effectiveness of the proposed control strategy.