Outlier-resistant observer-based H∞ PID control under stochastic communication protocol

Highlights：

• The purpose of this article is to find an outlier-resistant observer-based H∞ PID controller for discrete-time systems under the SCP scheduling. In this paper, the motivations of this paper are outlined as follows: 1) saturation constraint, as an active measure, can effectively suppress the influence of outliers on the system performance by targeting the measurement outliers caused by sensor failure and cyber attacks. However, the novel outlier-resistant observer-based H∞ PID control problem can not be solved by the existing control method, which needs to be solved urgently; 2) due to the data congestion caused by the limitation of network bandwidth, SCP is used to schedule the transmission sequence of network nodes to avoid data congestion. Nevertheless, the design of H∞ PID controller under the stochastic communication protocol has not gained adequate attention from scholars, it has great research significance to fill in such a gap.

• The main contributions of this article are highlighted in the following aspects: 1) according to our review of the existing results, the outlier-resistant observer-based H∞ PID controller design problem is firstly dealt with for a type of discrete-time systems under the SCP scheduling; 2) an observer model with saturation function is constructed to suppress the negative influence of measurement outliers, where the saturation level is dynamically adjusted in term of the previous observation errors; and 3) the stability and H∞ disturbance attenuation performance are analyzed in the simultaneous presence of abnormal measurements and SCP, in which a Markov chain is used to characterize the stochastic switching property of SCP.