Research on Equivalent Delay of Grid-connected Inverter System with High Switching Frequency and Low Control Frequency

With the advent of novel semiconductor materials, the switching frequency of inverters has substantially increased. This advancement is undoubtedly praiseworthy, but it has resulted in a significant surge in the computational load borne by the controller. To mitigate this issue, a scholar has reported a control scheme that utilizes a high switching frequency and a low control frequency to alleviate the computational burden on the controller. Nevertheless, the system equivalent delay, which is one of the key factors affecting the stability of the system based on this control scheme, has not been thoroughly investigated. In this paper, a theoretical derivations is conducted to calculate the delay of the control scheme. Simulation results to validate the derivation are shown.