The purpose of this study is to design a fractional-order super-twisting sliding-mode controller for a class of nonlinear fractionalorder systems.The proposed method has the following advantages:(1)Lyapunov stability ...The purpose of this study is to design a fractional-order super-twisting sliding-mode controller for a class of nonlinear fractionalorder systems.The proposed method has the following advantages:(1)Lyapunov stability of the overall closed-loop system,(2)output tracking error’s convergence to zero,(3)robustness against external uncertainties and disturbances,and(4)reduction of the chattering phenomenon.To investigate the performance of the method,the proposed controller is applied to an autonomous underwater robot and Lorenz chaotic system.Finally,a simulation is performed to verify the potential of the proposed method.展开更多
In order to improve the path tracking accuracy and robustness of the agricultural machinery navigation system,a sliding-mode variable-structure controller based on exact feedback linearization was presented.Firstly,ba...In order to improve the path tracking accuracy and robustness of the agricultural machinery navigation system,a sliding-mode variable-structure controller based on exact feedback linearization was presented.Firstly,based on the differential geometry theory and the affine nonlinear kinematics model,the corresponding nonlinear coordinate change matrix and nonlinear state variable feedback equations were deduced,and an exact feedback linearization model was then established.Secondly,based on the exact feedback linearization model,a sliding-mode variable-structure controller was designed by selecting suitable linear switching function and exponential reaching law.Finally,the comparative experiments were carried out.And the experimental results indicated that the proposed method had a high tracking accuracy and robustness.The maximum lateral error of the straight line tracking was less than 0.06 m,and maximum lateral error of the curve path tracking was less than 0.09 m.Experimental results show that the transplanter based on this automatic navigation system can effectively track the predefined path.展开更多
This paper proposes a finite-time consensus control algorithm based on nonlinear integral sliding-mode control for second-order multi-agent systems(MASs)with mismatched and matched disturbances.Firstly,a nonlinear fin...This paper proposes a finite-time consensus control algorithm based on nonlinear integral sliding-mode control for second-order multi-agent systems(MASs)with mismatched and matched disturbances.Firstly,a nonlinear finite-time disturbance observer is established to estimate the states and mismatched disturbances of the agent.Secondly,a dynamic integral sliding-mode(ISM)surface is designed by employing the estimates of mismatched disturbances.Then,based on the designed ISM and disturbance observer,the discontinuous or continuous campsite control protocols are respectively developed to guarantee the consensus for MASs in finite time with active anti-disturbance control.Finally,numerical simulation results illustrate the effectiveness of the proposed consensus control algorithm.展开更多
This paper presents detailed design steps of an effective control system aiming to increase the solar energy harvested via photovoltaic power-generation systems.The design of an intelligent maximum power point tracker...This paper presents detailed design steps of an effective control system aiming to increase the solar energy harvested via photovoltaic power-generation systems.The design of an intelligent maximum power point tracker(MPPT)supported by a robust sliding-mode(SM)controller is discussed in this study.The proposed control scheme is designed to track the MPP and provide a smooth system response by removing the overshoot in the load current during any variation in the connected load.Such a system is suitable for DC-DC buck converter applications.The study begins with modelling the buck converter for a continuous current mode operation.The reference voltage of the tracking system is produced by the proposed neural network(NN)algorithm.The proposed intelligent MPPT integrated with an SM controller is simulated in a MATLAB®/Simulink®platform.The simulation results are analysed to investigate and confirm the satisfaction level of the adopted four-serially connected PV-modules system.The system performance is evaluated at a light intensity of 500 W/m^(2) and an ambient temperature of 25°C.Applying only the proposed NN algorithm guarantees the MPP tracking response by delivering 100 W at a resistive load of 13Ω,and 200 W at a load of 6.5Ω,respectively,with 99.77%system efficiency.However,this simultaneously demonstrates a current spike of~0.5 A when the load is varied from 50%to 100%.The integrated SM controller demonstrates a robust and smooth response,eliminating the existing current spike.展开更多
文摘The purpose of this study is to design a fractional-order super-twisting sliding-mode controller for a class of nonlinear fractionalorder systems.The proposed method has the following advantages:(1)Lyapunov stability of the overall closed-loop system,(2)output tracking error’s convergence to zero,(3)robustness against external uncertainties and disturbances,and(4)reduction of the chattering phenomenon.To investigate the performance of the method,the proposed controller is applied to an autonomous underwater robot and Lorenz chaotic system.Finally,a simulation is performed to verify the potential of the proposed method.
基金Key Technologies R&D Program of Liaoning Province(Y5L7160701)National High-tech R&D Program of China(“863”Program)(2013AA040403).
文摘In order to improve the path tracking accuracy and robustness of the agricultural machinery navigation system,a sliding-mode variable-structure controller based on exact feedback linearization was presented.Firstly,based on the differential geometry theory and the affine nonlinear kinematics model,the corresponding nonlinear coordinate change matrix and nonlinear state variable feedback equations were deduced,and an exact feedback linearization model was then established.Secondly,based on the exact feedback linearization model,a sliding-mode variable-structure controller was designed by selecting suitable linear switching function and exponential reaching law.Finally,the comparative experiments were carried out.And the experimental results indicated that the proposed method had a high tracking accuracy and robustness.The maximum lateral error of the straight line tracking was less than 0.06 m,and maximum lateral error of the curve path tracking was less than 0.09 m.Experimental results show that the transplanter based on this automatic navigation system can effectively track the predefined path.
基金supported by the National Natural Science Foundation of China under Grant Nos.61673200and 61771231the Natural Science Foundation of Shandong Province of China under Grant Nos.ZR2018ZC0438and ZR2017MF010Key Research and Development Program of Yantai of China under Grant No.2019XDHZ085。
文摘This paper proposes a finite-time consensus control algorithm based on nonlinear integral sliding-mode control for second-order multi-agent systems(MASs)with mismatched and matched disturbances.Firstly,a nonlinear finite-time disturbance observer is established to estimate the states and mismatched disturbances of the agent.Secondly,a dynamic integral sliding-mode(ISM)surface is designed by employing the estimates of mismatched disturbances.Then,based on the designed ISM and disturbance observer,the discontinuous or continuous campsite control protocols are respectively developed to guarantee the consensus for MASs in finite time with active anti-disturbance control.Finally,numerical simulation results illustrate the effectiveness of the proposed consensus control algorithm.
文摘This paper presents detailed design steps of an effective control system aiming to increase the solar energy harvested via photovoltaic power-generation systems.The design of an intelligent maximum power point tracker(MPPT)supported by a robust sliding-mode(SM)controller is discussed in this study.The proposed control scheme is designed to track the MPP and provide a smooth system response by removing the overshoot in the load current during any variation in the connected load.Such a system is suitable for DC-DC buck converter applications.The study begins with modelling the buck converter for a continuous current mode operation.The reference voltage of the tracking system is produced by the proposed neural network(NN)algorithm.The proposed intelligent MPPT integrated with an SM controller is simulated in a MATLAB®/Simulink®platform.The simulation results are analysed to investigate and confirm the satisfaction level of the adopted four-serially connected PV-modules system.The system performance is evaluated at a light intensity of 500 W/m^(2) and an ambient temperature of 25°C.Applying only the proposed NN algorithm guarantees the MPP tracking response by delivering 100 W at a resistive load of 13Ω,and 200 W at a load of 6.5Ω,respectively,with 99.77%system efficiency.However,this simultaneously demonstrates a current spike of~0.5 A when the load is varied from 50%to 100%.The integrated SM controller demonstrates a robust and smooth response,eliminating the existing current spike.
