Modelling and simulation of grid-connected PV system in DIgSILENT/powerfactory

With a large number of PV power station integrated to the grid, some problems such as the grid-connected stability, relay protection, etc. brought out by it. In this paper, dynamic modelling and control strategy of grid-connected PV power stations were researched based on DIgSILENT. First, the equivalent model for PV power station was established consisting of PV arrays, power inverters, transformers, transmission line and grid. Second, control system including maximum power point tracking control, voltage and current double-loop control and relay protection control was modelled. Finally, based on a 10MW grid-connected PV power station in the northwest of China, simulations were given to verify the dynamic model and control strategy of PV power station.