轧机液压伺服系统多模型切换自适应反步控制
Adaptive backstepping control of multi-model switching for the hydraulic servo position system of a rolling mill
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摘要: 针对轧机液压伺服系统工作过程中弹性负载力和外负载力的跳变,基于公共Lyapunov函数方法和自适应反步控制方法,提出了一种多模型切换自适应反步控制策略.该方法结合自适应反步控制的特点和公共Lyapunov函数的设计要求,通过反步法设计了各子系统的状态反馈控制器和不确定上界参数的自适应估计器,取反步法的Lyapunov函数作为公共Lyapunov函数,保证了系统在任意切换下的渐近稳定.自适应反步法和公共Lyapunov函数方法的结合,便于公共Lyapunov函数的求取,又解决了同时存在参数跳变和参数慢时变的问题.仿真结果表明,该方法能够保证轧机液压伺服系统具有良好的动静态性能,并对参数跳变和参数慢时变具有较强鲁棒性.Abstract: To deal with the structure jumping problem resulting from elastic load force and external load force jumping in different working conditions, an adaptive backstepping control method of multi-model switching was presented based on the common Lyapunov function method and the adaptive backstepping method. This approach combines the features of adaptive backstepping control and the design requirements of a common Lyapunov function, and the adaptive controller for every sub-system and the parameter adaptive estimators for the uncertainty upper bound are designed by backstepping control, then taking the Lyapunov function designed by backstepping as a common Lyapunov function to ensure that the system is asymptotically stable under arbitrary switching. It is easy to select the common Lyapunov function by the combination of backstepping and the common Lyapunov function method, and the problem of parameter jumping and parameter slow time-varying existing at the same time is solved. Simulation results demonstrate that the designed controllers can ensure not only good dynamic and static performance for the hydraulic servo position system of a rolling mill, but also good robustness for the system parameter jumping and parameter slow time-varying.