| Due to the advantages of small size,strong overload capacity,reliable operation,and high torque/inertia ratio,permanent magnet synchronous motor(PMSM)is widely used in many areas,such as electric vehicles,robotics,and aerospace.However,PMSM is a complex system with strong coupling,strong nonlinearity and strong uncertainty,which brings difficulties and challenges to the design of motor speed regulation system.In order to improve the control quality of PMSM speed regulation system,it is necessary to reduce the adverse effects of measurement noise,external disturbance,parameter perturbation,and other uncertain factors.Aiming at the above issues,this dissertation takes PMSM speed regulation system as the research object,and carries out the research on measurement noise suppression,anti-disturbance control,adaptive control,and composite speed regulation control by utilizing high-order sliding mode algorithms.The main work and innovations of this dissertation are listed as follows:(1)A measurement noise suppression method based on the augmented sliding mode observer is proposed,which reduces the adverse effects of measurement noise on PMSM speed regulation system.Firstly,the limitations of conventional measurement noise suppression methods based on the low-pass filter and augmented extended state observer are analyzed from the perspective of frequency domain.Meanwhile,by utilizing the fixedtime and high-order sliding mode techniques,an augmented sliding mode observer is constructed to estimate the augmented state of the actual motor speed.Compared with conventional measurement noise suppression methods,this approach not only avoids the adverse effects of introducing the low-pass filter on the dynamic performance of motor speed regulation system,but also improves the estimation accuracy of system states.Finally,the experimental results verify that the proposed measurement noise suppression strategy can suppress the measurement noise in PMSM speed regulation system effectively.(2)A super-twisting sliding mode control method based on the finite-time extended state observer is proposed,which improves the anti-disturbance performance of PMSM speed regulation system.Firstly,by utilizing the finite-time technique,a finite-time extended state observer is designed to estimate the lumped disturbance of the speed regulation system,which ensures the finite-time convergence of the estimation error.Moreover,utilizing the estimation value as feedforward variable,a feedforward plus feedback control method is constructed by combining super-twisting control as feedback variable.The performance of the system is improved,and the finite time stability of the motor speed tracking error system is analyzed theoretically.This approach can not only reduce the chattering phenomenon existing in conventional sliding mode control,but also avoid the conservative selection of the controller gain.Finally,the experimental results verify that the proposed control strategy can significantly optimize the anti-disturbance performance of PMSM speed regulation system.(3)An adaptive super-twisting sliding mode control method based on the barrier function is proposed,which achieves dynamic suppression of time-varying lumped disturbance in PMSM speed regulation system.Firstly,an adaptive law with monotonically increasing control gain is designed to make the speed tracking error converges to a neighborhood near the origin in finite time.Meanwhile,adjusting the control gain of super-twisting sliding mode controller online by utilizing the barrier function,the speed tracking error can be guaranteed to stay in the predefined region.Specifically,when the motor speed tracking error gradually converges to the origin,the controller gain will be dynamically adjusted to a smaller value.When the tracking error gradually approaches the boundary of the predefined region,the controller gain can be dynamically tuned to a larger value to prevent the error from escaping out of the predefined region.It is worth noting that this approach does not require the prior knowledge of the upper bound of time-varying lumped disturbance and its derivative,and can avoid the overestimation of controller gain.Finally,the experimental results verify that the proposed control strategy can effectively suppress time-varying lumped disturbance in PMSM speed regulation system.(4)A composite continuous super-twisting sliding mode control method based on the novel disturbance observer is proposed,which improves the comprehensive performance of PMSM speed regulation system.Firstly,a disturbance observer is constructed by using the input-output model of PMSM speed regulation system to estimate the lumped disturbance.Its advantage is that only adjusting the unique parameter of the disturbance observer can change the estimation performance,thereby greatly reducing the parameter tuning workload.Moreover,the nonsmooth term is used to replace the discontinuous term in conventional super-twisting sliding mode controller,which solves the chattering problem still existing in super-twisting algorithm.Then,combining the novel disturbance observer with continuous super-twisting sliding mode control algorithm,the composite continuous super-twisting sliding mode controller is constructed.Finally,the experimental results verify that the proposed control strategy can significantly optimize the comprehensive performance of PMSM speed regulation system. |
