This paper explores the principle and characteristics of equivalent modeling of homologous photovoltaic systems.Considering the drawbacks of the scaling equivalent method

an aggregation equivalent approach

which maintains a constant converter impedance

is proposed.Based on a typical PV system

three distinct models were developed within the real time digital simulation framework:thirty 1 MW PV reference models

a singular 30 MW PV scaling model

and a 30 MW PV aggregation model with matching parameters.Simulation tests compared these models on several fronts

including fault ride-through

active power step response

frequency deviation

as well as impedance-frequency characteristics at the point of common coupling system.The results show that while the transient characteristics of the three models are basically the same

there are noticeable disparities between the impedance-frequency features of the scaling model and reference models.Conversely

the impedance-frequency characteristics of the aggregation model align with those of the reference model.