Partial decoupling control of chaos in permanent magnet synchronous motor
永磁同步电动机中混沌运动的部分解耦控制

Permanent magnet synchronous motor(PMSM) demonstrates chaotic phenomena when its parameters are in a certain range of values.Chaos degrades the performance of the motor drive systems;therefore it should be eliminated.The existing methods for chaos control in motor drive systems,whose control objective is limited to periodic orbits or equilibrium points,can not meet the practical requirement.To solve the problem,the partial decoupling control method based on nonlinear feedback is suggested to control the chaos in PMSM.The direct-axis and quadrature-axis stator voltages are used as the manipulated variables,by which the coupling terms in the direct-axis and quadrature-axis stator current equations are decoupled through the nonlinear feedback of the motor's states.As a direct result of the control force,the controlled system has a unique stable equilibrium point,which can be set to any value according to the practical requirement.At any time,once the partial decoupling control is used for the chaotic PMSM,the chaotic motion in PMSM will be stabilized at a predetermined equilibrium point.In this way,the chaos is eliminated in PMSM.The relationship between controlled system responses and control parameters is investigated,which gives guidance for parameter selection.The simulation results show that the theoretical analysis is correct and the method is effective.