The setup of a flexible test bench for the low-voltage-ride-through capability of solar energy converter

With increasing penetration of solar energies into power grids, the capability of low voltage ride through (LVRT) becomes a critical requirement for the grid-connected solar energy converters. As a result, many utility authorities have put up new codes and regulations to test the LVRT capability, while the converter manufacturers and the certification institutes have developed various test benches for the LVRT tests. Unlike those traditional test benches using physical devices, the Hardware-in-the-loop (HIL) platform offers much more flexibility and safer test environment, since electric grid and apparatus are digitally emulated on a real-time simulator (RTS). However, the RTS must feature an advanced solver, a fast processor and ultra-low latency to ensure the high fidelity of a simulation. This paper presents the configuration of a flexible test bench to test the LVRT capability of solar energy converters using the FPGA-based RTS. Besides flexibility, the accuracy of the RTS was demonstrated by comparing the real-time simulation result with the reference given by an offline simulation.