A New Method of Convolution Operation in the Scene of Superimposed Oscillation Components

The existing frequency domain convolution operation methods mainly focus on studying single frequencies and are difficult to adapt to the construction of small signal models in oscillation scenarios. Therefore, this article proposes a new convolution operation method suitable for the scenario of superimposing oscillatory components. Firstly, the frequency components contained in various electrical quantities under oscillation scenarios are analyzed, and the influence of oscillation components on the frequency domain characteristics of two-level converters is explained in detail. Secondly, a detailed frequency sequence matrix of the three-phase AC and DC components is constructed, accurately characterizing the multi-harmonic interaction coupling characteristics between the oscillation component and the fundamental frequency component. Furthermore, based on the frequency sequence, a matrix extension method suitable for convolution operations in oscillatory scenarios is proposed. Finally, a system model is built through an experimental simulation platform to verify the correctness and effectiveness of the proposed method.