Time-Domain Frequency Estimation Approach for Intelligent Control Systems

Health status of components of equipments in intelligent control systems affects the operation of systems and the quality of products. In the process of monitoring intelligent control systems, signal frequency analysis is often used to determine whether the equipment is faulty. Therefore, it is crucial to estimate the frequency of the operating signals effectively. Considering the disturbance and noise, a time-domain robust frequency estimation approach is proposed in this paper. Different from the frequency-domain methods, the proposed approach can estimate the frequencies of signal by constructing the subspace of disturbance and using the eigenvalue identification, which avoids the spectral leakage problem caused by the traditional frequency-domain method and has the advantage of simple calculation. Furthermore, the proposed approach can also reconstruct the original signal through the oblique projection. Finally, the effectiveness and feasibility of the approach are verified, which has a certain reference value.