Sliding mode control(SMC) becomes a common tool in designing robust nonlinear control systems, due to its inherent characteristics such as insensitivity to system uncertainties and fast dynamic response.Two modes are ...Sliding mode control(SMC) becomes a common tool in designing robust nonlinear control systems, due to its inherent characteristics such as insensitivity to system uncertainties and fast dynamic response.Two modes are involved in the SMC operation, namely reaching mode and sliding mode.In the reaching mode, the system state is forced to reach the sliding surface in a finite time.The major drawback of the SMC approach is the occurrence of chattering in the sliding mode, which is undesirable in most applications.Generally, the trade-off between chattering reduction and fast reaching time must be considered in the conventional SMC design.This paper proposes SMC design with a novel reaching law called the exponential rate reaching law(ERRL) to reduce chattering, and the control structure of the converter is designed based on the multiinput SMC that is applied to a three-phase AC/DC power converter.The simulation and experimental results show the effectiveness of the proposed technique.展开更多
For the problem of attitude control of a quad tilt rotor aircraft with unknown external disturbances, a class of control methods based on a new exponential fast nonsingular terminal sliding surface, a new fast reachin...For the problem of attitude control of a quad tilt rotor aircraft with unknown external disturbances, a class of control methods based on a new exponential fast nonsingular terminal sliding surface, a new fast reaching law, and a super twisting sliding mode disturbance observer is investigated. First, the new exponential nonsingular terminal sliding surface is designed by using the advantages of nonsingular terminal sliding mode finite time convergence and strong robustness. Second, to solve the problem of a long convergence time and the serious shaking of the traditional reaching law, a new fast reaching law model with characteristics of the second-order sliding mode is put forward. Third,considering the existence of complex disturbances, the super twisting sliding mode disturbance observer is used to estimate and compensate the composite disturbances online. Finally, compared with the traditional nonsingular fast sliding mode control, simulation results show that the proposed control scheme achieves a good control performance.展开更多
针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)...针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)最大功率点跟踪策略。首先,采用RBF神经网络对各种气象条件下的光伏电池输出电压进行预测;其次,设计非线性积分滑模面以改善传统滑模控制存在稳态误差及超调量大的问题;最后,设计新型指数趋近律,在加快收敛速度的同时有效削弱了系统高频抖振;通过Lyapunov函数分析非线性反步积分滑模控制的可达性与稳定性,并在静态、动态和遮光条件下进行仿真试验。仿真试验结果表明,在温度和光照强度发生变化的工况下,相比于传统滑模控制,基于RBF神经网络的非线性反步积分滑模控制能在各种气象条件下快速、准确地跟踪光伏系统最大功率点,具有较强的鲁棒性。展开更多
文摘Sliding mode control(SMC) becomes a common tool in designing robust nonlinear control systems, due to its inherent characteristics such as insensitivity to system uncertainties and fast dynamic response.Two modes are involved in the SMC operation, namely reaching mode and sliding mode.In the reaching mode, the system state is forced to reach the sliding surface in a finite time.The major drawback of the SMC approach is the occurrence of chattering in the sliding mode, which is undesirable in most applications.Generally, the trade-off between chattering reduction and fast reaching time must be considered in the conventional SMC design.This paper proposes SMC design with a novel reaching law called the exponential rate reaching law(ERRL) to reduce chattering, and the control structure of the converter is designed based on the multiinput SMC that is applied to a three-phase AC/DC power converter.The simulation and experimental results show the effectiveness of the proposed technique.
基金supported by the National Natural Science Foundation of China(11202162)
文摘For the problem of attitude control of a quad tilt rotor aircraft with unknown external disturbances, a class of control methods based on a new exponential fast nonsingular terminal sliding surface, a new fast reaching law, and a super twisting sliding mode disturbance observer is investigated. First, the new exponential nonsingular terminal sliding surface is designed by using the advantages of nonsingular terminal sliding mode finite time convergence and strong robustness. Second, to solve the problem of a long convergence time and the serious shaking of the traditional reaching law, a new fast reaching law model with characteristics of the second-order sliding mode is put forward. Third,considering the existence of complex disturbances, the super twisting sliding mode disturbance observer is used to estimate and compensate the composite disturbances online. Finally, compared with the traditional nonsingular fast sliding mode control, simulation results show that the proposed control scheme achieves a good control performance.
文摘针对最大功率点跟踪(Maximum power point tracking, MPPT)算法中传统滑模控制存在收敛速度慢、抖振显著等不足,提出一种基于RBF神经网络的光伏系统非线性反步积分滑模(Nonlinear backstepping integral sliding mode control, NBISMC)最大功率点跟踪策略。首先,采用RBF神经网络对各种气象条件下的光伏电池输出电压进行预测;其次,设计非线性积分滑模面以改善传统滑模控制存在稳态误差及超调量大的问题;最后,设计新型指数趋近律,在加快收敛速度的同时有效削弱了系统高频抖振;通过Lyapunov函数分析非线性反步积分滑模控制的可达性与稳定性,并在静态、动态和遮光条件下进行仿真试验。仿真试验结果表明,在温度和光照强度发生变化的工况下,相比于传统滑模控制,基于RBF神经网络的非线性反步积分滑模控制能在各种气象条件下快速、准确地跟踪光伏系统最大功率点,具有较强的鲁棒性。
