Networked Predictive Control System with Data Compression

Random time delay and frequency data dropout can degrade the performance of networked control systems and even cause system instability. Liu et al. (2004) introduced a networked model based predictive control scheme to tackle this problem. In his method, a set of control sequences for every possible delay time are packed together and sent to the plant side, and on the plant side the relevant control signal corresponding to the measured time delay is selected. It is an effective method to compensate for the network delay. However, it raises a new problem that it would increase the network traffic, because a sequence requires more transmitting time than a single value. To solve this problem, this paper consider a least square method which is applied to compress the control sequence before it is send to the network.feedback control system