Adaptive Robust Position Tracking Control And Experimental Research Of Alternating Current Asynchronous Motor

With the advantages of simple structure,low cost,and high reliability,alternating current(AC)asynchronous motors are widely used in various fields of social production and life,such as industry,agriculture,and manufacturing.However,AC asynchronous motors are multivariable,nonlinear,and strongly coupled,and are easily suffered from the various kinds of uncertainties,which bring certain challenges to the analysis and control of AC asynchronous motors.In order to improve the dynamic,static performance,and robust stability of AC asynchronous motor position system,and simplify the control structure of the system to a certain extent,this paper focuses on the research work in the following aspects:Firstly,the AC asynchronous motor mathematical model in the synchronous rotating coordinate system oriented by rotor flux is built based on the theory of coordinate transformation and the idea of vector control.Secondly,for the AC asynchronous motor position system with speed loop unmatched disturbance and current loop matched disturbance,a nonlinear disturbance observer(NDO)-based backstepping sliding mode control method is proposed.NDOs are constructed to dynamically observe the system uncertainties,and the observation values are introduced into the subsequently designed backstepping sliding mode controllers for compensation;the command filters are adopted to estimate the virtual control inputs and their derivatives,avoiding the “differential explosion” problem during the conventional backstepping method.Thirdly,for the AC asynchronous motor position system with speed loop unmatched disturbance and stator resistance perturbation,an immersion and invariance(I&I)theory-based adaptive control method is proposed.By constructing a nonlinear extended state observer(NLESO)to dynamically observe the unmatched disturbance of the system;the I&I theory-based adaptive estimator is designed for the stator resistance,which realizes the parameter estimation value converges to the real value asymptotically;the AC asynchronous motor position and flux tracking controllers are designed based on the I&I theory,which realizes precise tracking controls of the system rotor position and flux given values.Finally,for the AC asynchronous motor position system with speed/flux loop unmatched disturbance and current loop matched disturbance,a sliding mode observer(SMO)-based prescribed performance control method is proposed.A new improved exponential reaching law-based SMO is designed to observe the rotor flux;the AC asynchronous motor position and flux prescribed performance controllers are designed by combining the fuzzy adaptive method with a constraint handling strategy;an improved particle swarm optimization(IPSO)algorithm is adopted to optimize design the controllers parameters,which further improves the convergence speed and steady-state accuracy of the system;the effectiveness and feasibility of the proposed control method were verified by the comparative researches of simulation and d SPACE experiment.