一类高阶非线性系统的终端滑模复合控制

摘要

研究干扰观测器的控制与自适应终端滑模控制思想相结合,针对调整非线性系统跟踪误差,为了提高控制性能,提出一种适用于一类岛阶非线性系统的复合控制策略.通过引入干扰观测器对系统中存在的不确定进行估计,并利用估计结果对滑模控制输出进行补偿.根据干扰观测器的估计值设计自适应律,实现终端滑模控制器中的切换增益,根据系统扰动的大小进行自适应调节,从而改善由于固定切换增益所造成的滑模控制器输出量过大以及抖振等现象.基于Lyapunov理论证明了复合控制的稳定性,最后通过仿真进一步验证了控制策略的可行性及有效性.%Variable-Air-Volume (VAV) air-conditioning system has the feature of multi-variable, intense coupling and nonlinear. The coupling may directly affect the performance and the stability of VAV system. In this paper, a theoretical model of VAV air-conditioning system is established, which is the three input-output transfer function matrix. Based on the internal model, the analytical design of decoupling control method is used to design the decoupling controller. Its advantage is that absolute decoupling can be implemented, and moreover, the controller parameters can be tuned on-line in a monotonous manner to cope with the plant unmodelled dynamics. The simulation curves of the decoupling control system show the availability of the method.