Real time digital simulation (RTDS) of a novel battery-integrated PV system for high penetration application

In this paper, a photovoltaic (PV) system with energy storage elements (ESEs) is built in Real Time Digital Power System Simulator (RTDS) which is the partial work of future hardware-in-the-loop study of high-penetration multiple PV systems. Cascaded-multilevel inverter is applied as the power electronics interface among the PV array, batteries and grid. The H-bridges are modeled in RTDS small time-step environment while other power circuits and control system are realized in the large time-step main network. Interface transformer is used to connect the different time-step sub-networks. Difficulties of the system implementation in RTDS are discussed and solutions are provided. Finally, RTDS simulation results are given out and compared with Matlab/Simulink+PSIM results to verify the model.