Development of a Dynamic Photovoltaic Inverter Model with Grid-Support Capabilities for Power System Integration Analysis

As the interest in distributed energy resources (DERs) grows and more photovoltaic (PV) inverters are connected into the power grid, standards are being developed to tackle the high penetration of DERs. Newer DERs are required to provide grid-support functionality (GSF) to aid in regulating both voltage and frequency. With these advances in PV inverter technology, there exists a need for developing reliable dynamic models that emulate the behavior of these commercial devices with GSF capabilities. Herein, this paper presents a PV inverter model with GSF for power system analysis. The proposed model is composed of a dynamic mathematical PV module model, a state-space equations-based DC/DC converter tasked with maximum power point tracking and active power curtailment and a current controlled average PV inverter model. The model is designed to provide Volt-Var Curve and Frequency-Watt Curve control as well as to operate with voltage and frequency ride-through capabilities. The proposed PV inverter model is simulated utilizing MATLAB/Simulink. Simulation results are demonstrated for the proposed PV inverter model operating under various GSFs.