Detection of Harmonics and Interharmonics by Using Cascaded Limit Cycle Oscillators

Harmonics and interharmonics are a great concern in power systems. As a consequence, many works are addressing the detection of these disturbances. Traditional filters can be used to extract information from voltage and currents measurements. However, accurate estimation of these disturbances is challenging due to the large amount of frequency components that can be found in a single signal. In this paper, a method to detect harmonic and interharmonic components based on cascaded nonlinear limit cycle oscillators is presented. With the proposed method, these components can be extracted from the signal of interest even if their magnitudes change over time. Moreover, the proposed method is able to predict the frequency, phase and magnitude of each component with great accuracy. Simulation results performed in Matlab/Simulink are presented to validate the performance of the proposed technique.