Research on virtual inertia of three-phase grid connected converter based on filter

In today’s world where the energy crisis is growing excessively, the demand for integrating renewable energy is increasing, and the formation of microgrids is becoming an essential solution. The new microgrid system mainly relies on renewable energy sources, rather than traditional synchronous generators, and has low inertia issues. Taking the photovoltaic power generation system based on low-pass filter virtual inertia control as the research object, the electrical torque analysis method is used to establish the synchronous generator (SSG) model of the system. Based on the derivation results, the influence of virtual inertia control parameters on the system inertia, damping, and synchronization characteristics is analyzed. Research has shown that the energy storage effect of capacitors on a medium time scale can exhibit certain inertial characteristics. For control parameters, as the gain coefficient and cutoff frequency w of the low-pass filter increase, the inertia, damping, and synchronization characteristics of the system become stronger; Finally, the effectiveness of the control strategy and the correctness of the analysis conclusions were verified through simulation and experiments.