FFT-based monitoring procedure for intelligent control

Abstract

Performance monitoring plays an important role in intelligent control system. A fast Fourier transform (FFT) based monitoring method is proposed and has several advantages. Firstly, it is a frequency domain method, which can evaluate the performance of the controller before the disturbance comes into the system. Secondly, the method is very effective and convenient, and the testing time can be saved greatly, since only one ideal relay experiment is involved. Lastly, the frequency search range for on-line identification maximum closed-loop log modulus is extended. Simulation also shows that the proposed method can handle the process noise to some extent.