Dynamic equivalent impedance of photovoltaic plant and simulation analysis

This paper presents a new method for the dynamic equivalent impedance of grid-connected photovoltaic(PV) power plants which is built according to the topology of the grid-connected PV power plants. The simulation results are compared with the experimental results of the actual PV power plants by simulation with PSCAD/EMTDC and data processing with MATLAB to verify the accuracy of the model and the dynamic equivalent impedance. The error is below 6% which can meet the engineering application precision requirements. This method can clearly reflect the composition of PV power generation system structure, And the dynamic equivalent impedance model adapts to the volatility and intermittent of PV power generation, meet all kinds of environment and operation mode, Which proves that it has good practical reference value in optimizing control and relay protection.