Transient Performance Analysis of Aggregated VSG Models in Photovoltaic Power Plants

With the significant increase in the proportion of new energy power generation, power electronic devices represented by voltage source converters have been rapidly adopted in power systems, profoundly changing the structure of modern power systems. However, high-penetration renewable energy power systems face stability challenges. To address this issue, Virtual Synchronous Generator (VSG) technology has emerged. VSG technology virtualizes grid-connected inverters as synchronous generators, automatically regulating their active and reactive power output in response to fluctuations in grid voltage, frequency, and amplitude, providing crucial support to the grid. In the simulation analysis of photovoltaic power stations, current aggregation methods do not take into account the consistency of transient performance before and after aggregation. This paper modifies the voltage and current dual-loop control structure to achieve equivalent aggregation. Ten parallel-operated VSGs are equivalent to a single VSG with the same power rating. This achieves an equivalent aggregation method that does not affect transient response. The accuracy of the conclusion is validated through simulation.