EMT-Phasor Domain Hybrid Simulation of Distribution Grids with Photovoltaic Inverters

This paper presents the hybrid simulation technique to efficiently analyze the impact of high PV penetration on the distribution system. The proposed approach utilizes the multi-domain simulation capability of Matlab/Simulink software to simulate the tested system in the Electromagnetic Transient (EMT) and Phasor domains. The detailed switching models of several PV inverters are modeled in the EMT domain, while the rest, including other PV inverters and the grid, are modeled in the Phasor domain. An interaction method is proposed to handle data transferring between EMT and Phasor sub-systems. The modified IEEE 13-node distribution grid with several units of a two-stage single-phase smart PV inverter is used to validate the proposed technique. Several transient studies are carried out to analyze the accuracy and efficiency of the proposed hybrid method and compared with the full EMT model. Simulation results show that the proposed approach significantly reduces the computation time and retains sufficient accuracy as compared to full EMT model.