TCP网络的非线性自适应滑模控制

Nonlinear Adaptive Sliding Mode Control for TCP Networks

针对TCP网络存在网络参数高度变化和UDP流的情况,提出了两种非线性自适应滑模控制算法.考虑到系统不确定的上界很难获得,针对系统不确定的上界设计了一种自适应滑模控制器.由于使用了符号函数,该算法不能有效地抑制抖振.为此,设计了一种直接对不确定进行自适应的滑模控制器.仿真结果表明,对不确定的上界自适应的滑模控制器优于对上界自适应的滑模控制器,对上界自适应的滑模控制器优于PI控制器.

For the TCP network in the presence of highly variable network parameters and UDP flows, two nonlinear adaptive sliding mode control algorithms were presented. Because the upper bound of the system uncertainties could not easily be obtained, an adaptive sliding mode controller was presented based on the upper bound of the system uncertainties. However, the chattering could not be eliminated effectively with this algorithm because of the using of sign function. So, an adaptive sliding mode controller was presented to directly adapt the system uncertainties. Simulation results demonstrated that the adaptive sliding mode controller for the system uncertainties is superior to that for the upper bound, and the adaptive sliding mode controller for the upper bound is superior to PI controller.