Design of passivity-based control system for induction motors

Due to the great potential value in theory and application,nonlinear control strategies of induction motors,especially passivity-based control(PBC) methods,have been focused on.Passivity-based control is an undecoupling nonlinear feedback method using energy concept,and it analyzes the motor system and finds out the "workless force".In this way,the nonlinearity of the system need not be cancelled completely in the feedback control designing,therefore the control is simplified.At the same time,the torque and flux magnitude can be asymptotically tracked.In this paper,an induction motor model described by EulerLagrange equations is presented and decomposed as a feedback interconnection of an electrical and a mechanical passive subsystem.On this basis,the passivity-based torque and speed controllers were designed.The resulting control algorithm is globally stable without singularities and guarantees robustness to the overall system.Both the simulation and the experimental results prove that the control system based on this control law possesses nice static and dynamic performance and tracks reference speed well.