Hardware-in-the-loop simulation, modeling and close-loop testing for three-level photovoltaic grid-connected inverter based on RT-LAB

The hardware-in-the-loop (HIL) simulation testing for the controller of three-level photovoltaic grid-connected inverter is studied by RT-LAB, and a HIL simulation, modeling and testing scheme for photovoltaic grid-connected inverter is presented based on FPGA simulation and eHS modeling technology. First, a HIL testing platform, which contains PV array model, three-level photovoltaic inverter power circuit model, low voltage ride-through (LVRT) testing model and grid model, is constructed based on eHS modeling technology. And then the I/O physical interface circuit is constructed which connects the controller of three-level photovoltaic grid-connected inverter and signal condition module of RT-LAB simulator. Furthermore, open-loop testing of the controller is studied by the HIL testing platform and I/O physical interface circuit. Finally, the HIL close-loop testing for the controller is carried out in the normal grid and LVRT testing conditions by FPGA processor of RT-LAB simulator. Simulation testing results fully show the dynamic, static characteristics of the photovoltaic grid-connected inverter, and verify the validity of the proposed HIL simulation, modeling and testing scheme.