Delay Estimation of Dynamic System Based on Correlation Coefficient

In view of the situation that dynamic system's time-delay estimation methods are complicated and most of them need to know the system structure at first, a system time-delay estimation method based on the correlation coefficient is proposed in this paper. The implementation principle of this method is introduced in detail. The approach regards the system as a black box and does not need to know the system's structure. Through calculating the correlation coefficient of the input and output of the system, according to the variation law of the correlation coefficient, the time-delay of the system can be estimated. Simulation results show that this method has better recognition performance for low-order systems but it can easily be affected by the inertia parameter of high-order systems which maybe lead to some deviations in the results. Also, it is robust and accurate to system that contain oscillation.