Robust Adaptive Regulation And Asymptotic Tracking Control Of Magnetic Levitation Syste

This paper investigates two control problems in magnetic levitation systems:The oscillation caused by time-varying disturbance and the loss of the date when the information transmits over a communication network.The complex external environment is the main cause of system oscillation.How to eliminate the influence of unknown disturbance on the stability of maglev system is one of the main research contents of this paper.With the development of computer and communication technology,during the study of digital control,hybrid system and networked control system,quantized control shows the importance of theory and practice.Furthermore,the systematic study of control system with quantized control received great attention.The main motivation of considering quantization in maglev system is that it reduces communication rate and has sufficient accuracy,which effectively avoids data loss caused by communication network transmission.Therefore,this paper studys some control problems of magnetic levitation systems with quantized input and disturbances.The main contents of this paper are carried out from the following two aspects:Ⅰ.Robust adaptive regulation of magnetic levitation systems with input quantization and external disturbancesThis part successfully constructs a continuous robust adaptive feedback controller which stabilizes the position of the levitated electromagnet at the equilibrium point,by combining input quantization technique with two infinitesimal smooth functions.Compared with the existing methods,the proposed quantized control strategy not only guarantees the global stability with asymptotic state regulation of the system even if there are external disturbances,but also exhibits better performance than that of traditional PID control.The simulation validates the robustness and effectiveness of the proposed scheme.Ⅱ.Robust adaptive asymptotic tracking control of magnetic levitation systems with quantized input and disturbancesFirstly,this part dominates the uncontrollable nonlinearity of magnetic levitation systems by homeomorphic coordinate transformation.Next,this part not only introduces the adaptive law and the exponential decay term to eliminate external wind resistance and internal noise voltage respectively,but also combines the exponential decay term with the quantization decomposition method to compensate for the effect of quantization error.The continuous robust adaptive feedback controller is constructed to solve the asymptotic tracking problem of magnetic levitation systems with quantized input and disturbances.Finally,the simulation validates the effectiveness of the proposed control strategy.