An Approach on Adaptive Time-Delay Estimate and Compensation Control in Internet-Based Control Systems

A time-delay estimate algorithm for Internet-based control systems using the least mean square (LMS) filter algorithm was proposed. Modeling the time delay of Internet-based control systems as a nonlinear time series, the future time delay could be predicted by LMS algorithm. The simulation results showed that the proportion of time-delay prediction values, with prediction error of less 5%, reached 81.7% and the LMS algorithm can achieve ideal efficacy if time-delay has no variety abnormally. Based on the estimation time-delay online, an adaptive time-delay compensator was designed. An Internet-based water tank control system was used to demonstrate the validity of the designed time-delay compensator. The experimental results illustrated that the time-delay compensator can improve dynamic performance of the control system markedly.